As the Texas Department of Health has reported, there is a Shigella Outbreak in Lavaca County that has sickened nearly 100. It appears to be linked to a local food establishment, Los Cabos San Lucas Mexican Grill, in Hallettsville, Texas.

Introduction to Shigella

Shigella is a species of enteric bacteria that causes disease in humans and other primates. [16, 20] The disease caused by the ingestion of Shigella bacteria is referred to as shigellosis, which is most typically associated with diarrhea and other gastrointestinal symptoms. [11, 16] “Shigella infection is the third most common cause of bacterial gastroenteritis in the United States, after Campylobacter infection and Salmonella infection and ahead of E. coli O157 infection.” [19]

The global burden of shigellosis has been estimated at 165 million cases per year, of which 163 million are in developing countries. [23] More than one million deaths occur in the developing world yearly due to Shigella infection. [23, 29]  By one estimate, Shigella infections are responsible for 300,000 illnesses and 600 deaths per year in the United States. [25]  By another estimate, each year 450,000 Americans are infected with Shigella, causing 6,200 hospitalizations and 70 deaths. [27]

In general, Shigella is one of the most communicable and severe forms of the bacterial-induced diarrheas. [18] No group of individuals is immune to shigellosis, but certain individuals are at increased risk. [16] Small children acquire Shigellaat the highest rate, and [24, 28] persons infected with HIV experience shigellosis much more commonly than other individuals. [4]

Shigella is easily spread person-to-person because of its relatively tiny (compared to other bacteria) infectious dose. [16, 23]  Infection can occur after ingestion of fewer than 100 bacteria. [1, 16, 17]  Another reason Shigella so easily cause infection is because the bacteria thrive in the human intestine and are commonly spread both by person-to-person contact and through the contamination of food. [11, 22, 32]

The Discovery and Naming of Shigella

The several types of Shigella bacteria have been named after the lead workers who discovered each one. [11, 16, 20]   The first bacterium to be discovered, Shigella dysentariae, was named after Kiyoshi Shiga, a Japanese scientist who discovered it in 1896 while investigating a large epidemic of dysentery in Japan. [22, 37] The bacterium was also referred to more generally as the dysentery bacillus (the term “bacillus” referring to a genus of Gram-positive, rod-shaped bacteria of which Shigella is a member). [37] 

In a summary published annually, the CDC provides an overview of the classification of various types (species) of Shigella bacteria, as follows:

There are 4 major subgroups of Shigella, designated A, B, C and D, and 44 recognized serotypes. Subgroups A, B, C and D have historically been treated as species: subgroup A for Shigella dysenteriae; subgroup B for Shigella flexneri; subgroup C for Shigella boydii and subgroup D for Shigella sonnei. These subgroups and serotypes are differentiated from one another by their biochemical traits (ability to ferment D-mannitol) and antigenic properties. The most recently recognized serotype belongs to subgroup C (S. boydii). [12]

S. sonnei, also known as Group D Shigella, accounts for over two-thirds of shigellosis in the United States. Shigella flexneri, or group B Shigella, accounts for almost all the rest. [11, 19] More specifically, according to one recent study, “From 1989 to 2002, S. flexneri accounted for 18.4% of Shigella isolates submitted to CDC. [4] From 1973 to 1999, only 49 S. flexneri-associated outbreaks of foodborne disease were reported.” [32] In contrast, in developing countries, S. flexneri is the most predominant cause of shigellosis, but S. dysinteriae type 1 is still a frequent cause of epidemic throughout the developing world. [1, 16, 23, 37] 

The Incidence of Shigella Infection

The number of shigellosis cases reported annually to the Centers for Disease Control and Prevention (CDC) has varied over the past several years, from more than 17,000 during 1978–2003, to an all-time low of 14,000 in 2004, to almost 20,000 in 2007. [11, 19] But most cases go undiagnosed or unreported. [12, 16, 37]  In one study done in Oregon, 430 confirmed Shigella cases from July 1995 through June 1998 were examined. [30] Among the several findings about those most likely to fall ill was the following:

Of 430 isolates, 410 were identified to the species level: Shigella sonnei accounted for 55% of isolates, and Shigella flexneri, for 40%. The overall annual incidence of shigellosis was 4.4 cases per 100,000 population. Children aged [less than] 5 years (annual incidence, 19.6 cases per 100,000 population) and Hispanics (annual incidence, 28.4 cases per 100,000 population) were at highest risk. [30] 

The CDC estimates that 450,000 total cases of shigellosis occur in the U.S. every year. [4, 11, 21] Shigellosis is also characterized by seasonality, with the largest percentage of reported cases occurring between July and October, and the smallest proportion occurring in January, February, and March. [19] Sporadic (or non-outbreak) infections account for the majority of cases and, in general, the exact means by which persons are infected (risk factors) are not yet well documented or understood. [21, 36]

Shigella is an especially common cause of disease among young children, in large part because it is difficult to control the spread of the bacteria in daycare settings. [16, 28] The symptoms of shigellosis vary so widely that children shedding Shigella in their stool may exhibit no symptoms of infection.  A person infected with Shigella can be asymptomatic (show no symptoms of illness), suffer from moderate to severe diarrhea, or suffer complications up to and including death. [11, 17, 26] 

More on Incidence Rates and How Shigella is Transmitted

As previously noted, Shigella species are transmitted by the fecal-oral route, and most infections are transmitted from person to person, reflecting the low infectious dose. [19] As also noted, as few as ten Shigella bacteria can result in clinical infection. [17] Where persons who are infected may be present, the risk of transmission and infection increases with poor hand hygiene, ingestion of contaminated food or water, inadequate sanitation and toileting, overcrowding, and sexual contact. [4, 14, 21, 24, 28] Shigella bacteria are present in the stools of infected persons while they are sick and for up to a week or two afterwards. [11, 16, 17] It is estimated that up 80% of all infection is the result of person-to-person transmission. [17]

Because of its quite common person-to-person spread, shigellosis has long been associated with outbreaks in daycare centers, nursing homes, institutional settings (like prison), and cruise ships. [11, 14, 17, 23, 24] Explaining the significance of daycare centers as a source of Shigella infection, one well-respected study explains as follows:

High shigellosis rates in children are attributable to several factors. Young children are unable to practice good personal hygiene and have not yet acquired immunity to S. sonnei. The infectious dose is as low as 10–200 organisms, and person-to-person transmission is highly effective. Day-care centers play an important role in the person-to-person spread of shigellosis and its subsequent dissemination in communities. Inadequate hand washing, diapering practices, and fecal contamination of water-play areas, such as kiddie pools, have been associated with S. sonnei transmission in day-care centers. [19]

Several studies have demonstrated an increased frequency of shigellosis cases in young adult men residing in urban settings who have little, if any, exposure to these traditionally recognized risk groups. [4, 36] Although some of these studies indicated that sex between men can be a risk-factor, most of these studies occurred before the HIV epidemic. [4, 23] 

Shigella infections also may be acquired from eating contaminated food. A study published in 2010 estimated more than one-third of U.S. shigellosis cases annually might be caused by the consumption of contaminated food. [21] In the United States, incidence of foodborne illness is documented through FoodNet, a reporting system used by public health agencies that captures foodborne illness in over 13% of the population. [8, 9] Of the 10 pathogens tracked by FoodNet, Salmonella,Campylobacter, and Shigella are responsible for most cases of foodborne illness. [27] An estimated 20% of the total number of cases of shigellosis involve food as the vehicle of transmission. [27]

In one oft-cited study summarizing food-related illness and death in the United States, the following synopsis is set forth at the end, summarizing Shigella.

Reported cases: Outbreak-related cases based on reports to CDC, 1983-1992. Passive surveillance estimate based on average number of cases reported annually to CDC, 1992-1997. Active surveillance estimate based on extrapolation of average 1996-1997 FoodNet rate to the 1997 U.S. population.

Total cases:  Because Shigella frequently causes bloody diarrhea, total cases assumed to be 20 times the number of reported cases, based on similarity to E. coli O157:H7.

Hospitalization rate:  Based on hospitalization rate for culture-confirmed cases reported to FoodNet, 1996-1997.

Case-fatality rate: Average case-fatality rate among cases reported to FoodNet, 1996-1997 (23,24).  Percent foodborne: Assumed to be 20%. Although most cases are due to person-to-person transmission (60),

foodborne outbreaks are responsible for a substantial number of cases [27]

According to the CDC, Shigella is the third most common pathogen transmitted through food. In FoodNet surveillance areas in 2008, the rate of Shigella was 6.6 per 100,000 population, exceeded only by Salmonella (15.2/100,000) and Campylobacter (12.7/100,000). [10] During 2006, public health officials reported a total of 1,270 foodborne-related outbreaks from 48 states in the U.S. [9] Although Shigella was responsible for only 10 (1%) of those outbreaks, 183 confirmed cases of shigellosis were nonetheless reported. [9] This reporting rate contrasts with an average of 659 cases annually in the previous five years, making it potentially an aberration or outlier.

Shigella is also responsible for a substantial portion of foodborne outbreaks on cruise ships. [16, 34] In a review of cruise ship outbreaks worldwide over several years, 16% of outbreaks were attributed to Shigella, affecting over 2,000 passengers. [34] Sanitation violations related to food handling and communicable disease have decreased substantially, however, over the past 15 years. [14]

Symptoms of Shigella Infection

Most people who are infected with Shigella develop diarrhea, fever, and stomach cramps after being exposed to the bacteria. [11, 16, 26] Symptoms may start 12 to 96 hours after exposure, usually within 1 to 3 days. [1, 16] Diarrhea may range from mild to severe, and it usually contains mucus. [16] When more severe, the diarrhea is bloody 25% to 50% of the time. [1, 16, 22] Rectal spasms, which are technically referred to as “tenesmus,” are common. [16] 

Shigellosis usually resolves in 5 to 7 days. [1, 11, 26] A severe infection with high fever may be associated with seizures in children less than two years old. [16, 19] Some persons who are infected may have no symptoms at all but may still pass the Shigella bacteria to others. [11, 17] 

Persons with shigellosis in the U.S. do not often require hospitalization, although the hospitalization rate has been estimated to be more than 50,000 per year. [27] Predictably, the hospitalization rate tends to be highest among older individuals. [9, 10, 16] Those who are immune compromised, like persons infected with HIV, are also more likely to face hospitalization because of the risk of complications. [4] 

The relationship between HIV infection and the subsequent risk for shigellosis has yet to be conclusively evaluated, although it is known that “HIV-associated immunodeficiency leads to more severe clinical manifestations of Shigellainfection.” [23] Moreover, persons infected with HIV “may develop persistent or recurrent intestinal Shigella infections, even in the presence of adequate antimicrobial therapy. They also face an increased risk of Shigella bacteraemia, which can be recurrent, severe or even fatal.” [23]

What are the serious and long-term risks of Shigella infection?

Persons with diarrhea caused by S. sonnei usually recover completely, although it may be several months before their bowel habits are entirely normal. [1, 11, 26] About 2% of persons who are infected with S. flexneri later develop pains in their joints, irritation of the eyes, and painful urination—something typically diagnosed as Reiter’s Syndrome. [1, 6] 

Reiter’s syndrome is more generally referred to as reactive arthritis, a complication that accompanies other kinds of bacterial infections as well. [27, 37] This complication occurs because the immune system, intending to fight Shigella, attacks the body instead. [6, 31]  Reactive arthritis is most common in persons with the HLA-B27 gene. [31] (About 80% of people with reactive arthritis have the HLA-B27 gene. Only 6% of people who do not have the syndrome have the HLA-B27 gene.) Reactive arthritis can last for months or years and may be difficult to treat. [6]

Once someone has suffered a Shigella infection, a certain level of immunity develops, meaning that the person is not likely to get infected with that specific type again for at least several years. [16] This temporary immunity does not, however, protect against other types of Shigella. [16, 29]

Shigella bacteria multiply in the human intestinal tract and invade the cells, which results in much tissue destruction. [29] Many strains produce a toxin called Shiga toxin, which is very potent and destructive. [16, 22] Shiga toxin is very similar to the verotoxin of E. coli O157:H7. Complications of shigellosis include severe dehydration, seizures in small children, rectal bleeding, and invasion of the blood stream by the bacteria (bacteremia or sepsis). [1, 11, 16, 26]  In some cases, the bacteria that cause shigellosis may also cause inflammation of the lining of the rectum (proctitis) or rectal prolapse. [26]

In rare cases (but more common in S. dysenteriae infection), there can also be a deadly complication called “toxic megacolon.” [1, 26] This rare complication occurs when the colon becomes paralyzed, preventing bowel movements or passing gas. [16, 26] Signs and symptoms include abdominal pain and swelling, fever, weakness, and disorientation. [26] Untreated, the colon may rupture and cause peritonitis, a life-threatening condition requiring emergency surgery. [26] 

The other relatively rare complication that can occur with a Shigella infection is the development of hemolytic uremic syndrome. This rare complication is more commonly caused by E. coli O157:H7, and it can lead to a low red blood cell count (hemolytic anemia), low platelet count (thrombocytopenia), and acute kidney failure. [26, 37]  It is more common to develop HUS after being infected with S. dysenteriae. [1]

Diagnosis and Treatment of Shigella Infections

Because the symptoms of a Shigella infection are consistent with a fairly large number of potential illnesses, including most foodborne infections, a diagnosis must be confirmed by a laboratory test. [5, 11, 26] First a stool sample must be obtained from the potentially infected person, and then the sample is placed on a medium to encourage the growth of bacteria. If and when there is growth, the bacteria are identified, usually by looking at the growth under a microscope. [20, 26] The laboratory can also do special tests to tell which species of Shigella the person has, and which antibiotics would be best to treat the infection. [16, 22, 30]  Antibiotic-sensitivity tests are important because Shigella is often resistant to multiple antibiotics. [16, 30] 

More advanced testing and surveillance methods, such as plasmid profiling and chromosomal fingerprinting, can also be used. [11, 20, 29] So-called “genetic fingerprinting” of the bacterial isolate, using pulsed-field gel electrophoresis (PFGE) is a molecular technique that can help to characterize Shigella isolates, whether obtained from human or food samples. [11, 27] Taken together, all of these tests can assist public health officials in determining whether cases (confirmed infections) are isolated or associated with common-source outbreaks. [19, 20, 27] 

Efforts to identify outbreaks of foodborne illness—whether caused by Shigella or other pathogens—are important to preventing the secondary spread of infection, especially with bacteria as highly communicable as Shigella. [1, 11, 21] One major advance in these efforts was the creation of FoodNet, an active surveillance system for foodborne illness. As described by the CDC, 

FoodNet workers regularly contact more than 300 laboratories for confirmed cases of foodborne infections in 10 states encompassing a population of more than 44 million persons. In addition to monitoring the number of Shigella infections, investigators monitor laboratory techniques for isolation of bacteria, perform studies of ill persons to determine exposures associated with illness, and administer questionnaires to people living in FoodNet sites to better understand trends in the eating habits of Americans. [11]

Although shigellosis is usually a self-limited illness, antibiotics can shorten the course, and in the most serious cases, might be lifesaving. [1, 16, 22] Historically, the antibiotics commonly used for treatment of bacterial infections, like those caused by Shigella, are ampicillin, trimethoprim/sulfamethoxazole (TMP-SMZ, also known as Bactrim or Septra), or ceftriaxone (Rocephin). [1, 11, 26]  Ciprofloxacin is also used commonly to treat adults who are infected. [11, 26, 30].  

Unfortunately, Shigella bacteria have become resistant to one or more of these antibiotics. [16, 30] This means some antibiotics might not be effective for treatment, and that using (or overusing) antibiotics to treat shigellosis can sometimes make the bacteria more resistant. [30] As noted in one recent study, 

Of 369 isolates tested, 59% were resistant to TMP-SMZ, 63% were resistant to ampicillin, 1% were resistant to cefixime, and 0.3% were resistant to nalidixic acid; none of the isolates were resistant to ciprofloxacin. Thirteen percent of the isolates had multidrug resistance to ampicillin, chloramphenicol, streptomycin, sulfisoxazole, and tetracycline. Infections due to multidrug-resistant shigellae are endemic in Oregon. [30]

This study therefore suggests that “[n]either ampicillin nor TMP-SMZ should be considered appropriate empirical therapy for shigellosis any longer; when antibiotics are indicated, a quinolone or cefixime should be used.” [30]

The Economic Impact of Shigella Infections

The USDA Economic Research Service (ERS) published its first comprehensive cost estimates for sixteen foodborne bacterial pathogens in 1989. [32]  Five years later, it was estimated that the medical costs and productivity losses that Shigella infections caused each year ran from $907 million to over $1 billion, based on an estimate of 2.1 million cases and between 120-360 deaths. [13] The average length of a related hospital stay was 4.6 days, with the cost (based on a 1990 average cost per day of $687) was $16,888. [13]

Using a different kind of economic analysis, this same 1996 study estimated that the annual cost of Shigella infections was $63 million, while the average cost of each confirmed and treated infection was $390; however, these estimates are based on significantly lower (and outdated) incidence and death rates. [13] Most recent estimates are all much higher. For example, a study published in 2010 estimated the cost per case (in 2009 dollars) for a treated Shigella infection to be $7,092, with an estimate of 96,686 cases and 1,227 deaths per year, and a total cost to U.S. residents of $686 million. [35]

Real Life Impacts of Shigella Infection

Because the illnesses caused by the ingestion of Shigella bacteria range from mild to severe, the real-life impacts of Shigella infection vary from person to person.  

While anyone can become ill with Shigella infection, very young children, the elderly, and persons with compromised immune systems are most likely to develop severe illness.  

  • About 2% of persons who are infected with one type of ShigellaShigella flexneri, later develop pains in their joints, irritation of the eyes, and painful urination. This is called post-infectious arthritis, or reactive arthritis.   The arthritis can last for months or years and can lead to chronic arthritis.  Post-infectious arthritis is caused by a reaction to Shigella infection that happens only in people who are genetically predisposed to it. [11]
  • An unknown percentage of patients with Shigella infections develop digestive disorders, including irritable bowel syndrome.

Although most patients with Shigella infections recover within a few months, some continue to experience complications for years.

One woman whose life was permanently altered by this devastating pathogen volunteered to share her story:

How to Prevent Shigella Infection

According to the World Health Organization, “Despite the continuing challenge posed by

Shigella, there is room for optimism as advances in biotechnology have enabled the development of a new generation of candidate vaccines that shows great promise for the prevention of Shigella disease.” [23] But such a vaccine has yet to be perfected. Thus, in the meantime, preventing infection is the best approach, and that means implementing proper sanitation measures. [1, 14]  Indeed, as noted in one authoritative text summarizing the research,

A safe water supply is important for the control of shigellosis and is probably the single most important factor in areas with substandard sanitation facilities. Chlorination is another factor important in decreasing the incidence of all enteric bacterial infections. Of critical importance to the establishment of a safe water supply is the general level of sanitation in the area and the establishment of an effective sewage disposal system. [16]

As previously noted, it takes but a few—far less than 100—Shigella bacteria to cause infection. [17]  Moreover, a person can be infectious even if there are no symptoms, either because he remained asymptomatic (never exhibited symptoms of shigellosis), or because the person continued to shed the bacteria in his stool for a week or two after recovering. [11, 16, 17] 

The spread of Shigella from an infected person to other persons can be avoided by frequent and careful handwashing with soap and hot water. [1, 14, 15] Handwashing among children should be frequent and supervised by an adult in daycare centers and homes with children who have not been fully toilet trained. [24, 28] 

If a child in diapers has shigellosis, everyone who changes the child’s diapers should be sure the diapers are disposed of properly in a closed-lid garbage can and should wash his or her hands and the child’s hands carefully with soap and warm water immediately after the diaper has been changed. [15, 39] After use, the diaper changing area should be wiped down with a disinfectant such as diluted household bleach, Lysol, or bactericidal wipes.  [15, 24, 39] When possible, young children with a Shigella infection who are still in diapers should not be in contact with uninfected children. [1, 11, 15]

Basic food safety precautions and disinfection of drinking water should prevent Shigella bacteria from contaminating food and water. [11, 15, 39] Nonetheless, it should go without saying that people with shigellosis should not prepare food or drinks for others until they have been confirmed (by a stool culture) to no longer be shedding Shigella bacteria in their stool. [1, 15]  At swimming beaches, there should be bathrooms and handwashing stations near the swimming area to help keep the water from becoming contaminated.  [14, 29] Daycare centers should not provide water play areas. [24]

Simple precautions taken while traveling to the developing world can prevent shigellosis. [1, 39] Drink only treated or boiled water, and eat only cooked hot foods or fruits you peel yourself. [1, 11] The same precautions prevent other types of traveler’s diarrhea. [39]


  1. American Public Health Association (APHA), “Shigellosis,” in CONTROL OF COMMUNICABLE DISEASES MANUAL, pp. 556-60, edited by Heymann, David L., (19th Ed. 2008).
  2. Angulo, F.J., et al., “Antimicrobial Use in Agriculture: Controlling the Transfer of Antimicrobial Resistance to Humans,” SEMINARS IN PEDIATRIC INFECTIOUS DISEASES, Vol. 15, No. 2, pp. 78-85 (April 2004).
  3. Angulo, F.J., et al., “Evidence of an Association Between Use of Anti-microbial Agents in Food Animals and Anti-microbial Resistance Among Bacteria Isolated from Humans and the Human Health Consequences of Such Resistance, JOURNAL OF VETERINARY MEDICINE, Series-B, Vol. 51, Issue 8-9, pp. 374-79 (Oct. 2004).
  4. Baer, JT, et al., “HIV Infection as a Risk Factor for Shigellosis,” EMERGING INFECTIOUS DISEASESVol. 5, No. 6, pp. 820-823 (1999).  Full text available online at
  5. Bennett,  JV, et al., “Infectious and Parasitic Diseases,” AMERICAN JOURNAL OF PREVENTIVE MEDICINE, Vol. 3, pp. 102–14 (1987).
  6. Carter, JD and Hudson, AP, “Reactive Arthritis: Clinical Aspects and Medical Management,” RHEUMATIC DISEASE CLINICS OF NORTH AMERICA, Vol. 35, No. 1, pp. 21-44 (Feb. 2009). Abstract available online at
  1. Buzby, Jean and Roberts, Tonya, “The Economics of Enteric Infections: Human Foodborne Disease Costs,” GASTROENTEROLOGY,  Vol. 136, No. 6, pp. 1851-62 (May 2009).  Abstract available online at
  2. CDC, “Preliminary FoodNet data on the incidence of foodborne illnesses – Selected sites, United States, 1999,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 49, No. 10, pp. 201-03 (March 17, 2000).  Available online at
  3. CDC, “Preliminary FoodNet Data on the Incidence of Infection with Pathogens Transmitted Commonly through Food—10 States, 2006,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 56, No. 14, pp. 336-9 (April 13, 2007).  Available online at
  4. CDC, “Preliminary FoodNet Data on the Incidence of Infection with Pathogens Transmitted Commonly through Food—10 States, 2009,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 59, No. 14, pp. 418-22 (April 16, 2010).  Available online at
  5. CDC, National Center for Zoonotic, Vector-Borne, and Enteric Diseases, “Shigellosis—General Information and Frequently Asked Questions,” (updated: Nov.16, 2009).  Available online at
  6. CDC, SHIGELLA SURVEILLANCE: ANNUAL SUMMARY: 2005 (2007).  Available online at
  7. Council for Agriculture, Science and Technology (CAST), “Foodborne Pathogens: Risks and Consequences: Task Force Report No.122,” pp. 1-87 (Sept. 1994).   Full text available online at
  8. Cramer, EH, Blanton CJ, and Otto C., “Shipshape: Sanitation Inspections on Cruise Chips, 1990-2005,” CDC Vessel Sanitation Program, JOURNAL OF ENVIRONMENTAL HEALTH, Vol. 70, No. 7, pp. 15-21 (March 2008).  Full text available online at
  9. Doyle, MP, et al., “Reducing Transmission of Infectious Agents in the Home,”  DAIRY, FOOD AND ENVIRONMENTAL SANITATION, Vol. 96, No. 1, pp. 330-37 (June 2000).
  10. DuPont, HL, “Shigella species (bacillary dysentery),” in Mandell, Douglas, and Bennett’s PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASES, Fifth Edition,. p. 2363-9 (2000, Mandell, Bennett, and Dolan, Editors)
  11. DuPont, HL, et al., “Inoculum Size in Shigellosis and Implications for Expected Mode of Transmission,”  THE JOURNAL OF INFECTIOUS DISEASES, Vol. 159, No. 6, pp. 1126-28 (June 1989).  Available for purchase online at
  12. Gomez HF, et al., “Lactoferrin Protects Rabbits from Shigella flexneri-Induced Inflammatory Enteritis,” INFECTION AND IMMUNITY, Vol. 70, No. 12, pp. 7050-53 (Dec. 2002). Full text at
  13. Gupta, Amita, et al., “Laboratory-confirmed Shigellosis in the United States, 1989–2002: Epidemiologic Trends and Patterns,” CLINICAL INFECTIOUS DISEASES, Vol. 38, pp. 1372–77 (May 15, 2004).  Full text available at
  14. Hale, TL and Keusch, GT, “Shigella: Structure, Classification, and Antigenic Types,” in BARON’S MEDICAL MICROBIOLOGY (4th ed. 1996).
  15.  Haley, CC, et al., “Risk Factors for Sporadic Shigellosis, FoodNet 2005,” FOODBORNE PATHOGENS AND DISEASES, Vol. 7, pp. 741–47 (July 72010).  Abstract available online
  16. Keusch, GT and Acheson, DW, “Shigella Infection,” in ENTERIC INFECTIONS AND IMMUNITY (1996).
  17. Kotloff, K. L., et al., “Global burden of Shigella infections: implications for vaccine development and implementation of control strategies,” BULLETIN OF THE WORLD HEALTH ORGANIZATION, Vol. 77, No. 8 (1999).  Full text available online at
  18. Krilov, LR, et al., “Impact of an infection control program in a specialized preschool,” AMERICAN JOURNAL OF INFECTION CONTROL, Vol. 24, pp. 167-173 (1996).  Abstract available online  at
  19. Lee, LA, et al., “Hyperendemic Shigellosis in the United States: A Review of Surveillance Data for 1967–1988,” JOURNAL OF INFECTIOUS DISEASES, Vol. 164, pp. 894-900 (Nov. 1991).  Full text available for purchase online at
  20. Mayo Clinic, “Shigella. Infection,”  Mayo Clinic Web site, information last updated April 14, 2010, at
  21. Mead, Paul M, et al., “Food-related Illness and Death in the United States,” EMERGING INFECTIOUS DISEASES, Vol. 5, No. 5, pp. 607-25 (September-October 1999).  Full text available online at
  22. Mohle-Boetani, JC, et al., “Communitywide Shigellosis: Control of an Outbreak and Risk factors in Child Day-Care Centers,” AMERICAN JOURNAL OF PUBLIC HEALTH, Vol. 85, pp. 812-6 (1995). Full text available online at
  23. Philpott, DJ, Edgeworth, JD, and Sansonetti, PJ, “The Pathogenesis of Shigella flexneri Infection: Lessons from in vitro and in vivo studies,” PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY—BIOLOGICAL SCIENCES,  Vol. 355,  pp. 575-586 (2000).  Full text available online at
  24. Replogle, Marilyn, et al., “Emergence of Antimicrobial-Resistant Shigellosis in Oregon,” CLINICAL INFECTIOUS DISEASE (2000) 30 (3): 515-519 (2000). Full text available online at
  25. Ringrose, JH, et al., “Influence of Infection of Cells with Bacteria Associated with Reactive Arthritis on the Peptide Repertoire Presented by HLA-B27,”  JOURNAL OF MEDICAL MICROBIOLOGY, Vol. 50, pp. 385-389 (2001). Full text available online at
  26. Reller, ME, et al., “A Large, Multiple-Restaurant Outbreak of Infection with Shigella flexneri serotype 2a Traced to Tomatoes,” CLINICAL INFECTIOUS DISEASES, Vol. 42, No. 2, pp. 163-169 (2006). Full text available online at
  27. Roberts, T, “Human Illness Costs of Foodborne Bacteria,” AMERICAN JOURNAL OF AGRICULTURE ECONOMICS, Vol. 71, No. 2, pp. 468-474 (1989).  Full text available for purchase online at
  28. Rooney, RM, et al., “A Review of Outbreaks of Foodborne Disease Associated with Passenger Ships: Evidence for Risk Management,” PUBLIC HEALTH REPORTS, Vol. 119, No. 4, pp. 427-434 (July-August 2004).  Full text available online at
  29. Scharf, Robert, “Health-Related Costs from Foodborne Illness in the United States,” The Produce Safety Project at Georgetown University (March 3, 2010).  Full text available online at
  30. Tauxe, RV, et al., “The Persistence of Shigella flexneri in the United States: Increasing Role of Adult Males,” AMERICAN JOURNAL OF PUBLIC HEALTH, Vol. 78, No. 11, pp. 1432-5 (Nov. 1988). Full text available online at
  31. Trofa, Andrew, et al., “Dr. Kiyoshi Shiga: Discover of Dysentery Bacillus,” CLINICAL INFECTIOUS DISEASES, Vol. 29, pp. 1303-06 (1999).  Full available online at
  32. USDA Economic Research Service, “Bacterial Foodborne Disease—Medical Costs and Productivity Losses,” AER-741, August 1996 (authors: Jean C. Buzby, et al.).  Full text available online at
  33. Wallinga, D, “Antimicrobial Use in Animal Feed:  An Ecological and Public Health Problem,” MINNESOTA MEDICINE, Vol. 85, No. 10 pp. 12-16 (Oct. 2002).  Full text available online at
  34. Weinberg, Winkler, NO GERMS ALLOWED! HOW TO AVOID INFECTIOUS DISEASES AT HOME AND ON THE ROAD 72 (Rutgers Univ. Press 1996). 

I am off to Tribeca next week for the showing of “Poisoned.” It is odd, and more than a bit humbling, to have a documentary that has so much of my work of the last 30 years. My hope is that viewers listen to all the great people (present company excluded) interviewed and take to heart the message that we can make even more advances in producing safe and nutritious food.

In the meantime, I will crack a broad grin with this email I received today in response to my post over at Food Safety News about vaccinating food service workers against the hepatitis A virus.

Mr. Marler,

I so appreciate the service that this newsletter provides. As the operations manager for a food manufacturer, I read your posts first thing everyday and often use your messages to inform our employees of health concerns. We had an outbreak of Hepatitis A at a Western Sizzler in Ooltewah, TN a few years back that resulted in several of their customers becoming ill and ultimately shuttered the restaurant. We started offering the shots to our workers at that time and after the incident at Famous Andy’s in VA we made it mandatory.

We have a local pharmacy that keeps the vaccine on hand for us and we pay all of the expenses.

It is amazing to us that all food establishments don’t do the same as part of their business continuity plan. Keep preaching your message and for sure keep your format for timely information going.


(Name redacted)

Interesting reading in Chemical Research in ToxicologyIs Baikiain in Tara Flour a Causative Agent for the Adverse Events Associated with the Recalled Frozen French Lentil & Leek Crumbles Food Product? – A Working Hypothesis

On June 17, 2022, Daily Harvest (New York, NY) issued a voluntary recall of about 28,000 units of their newly launched French Lentil & Leek Crumbles frozen food product (1 serving size, 113 g) due to gastrointestinal (GI) issues. Case counts received by the FDA total 393 adverse illness events and 133 hospitalizations related to the consumption of this product within 39 US states due to complaints of GI, liver, gallbladder, and(or) bile duct problems.

Initial testing of the frozen food product resulted in negative results for common food toxicants, microbial pathogens, mycotoxins, major allergens, heavy metals, pesticides, hepatitis A, and norovirus. Out of the 27 components in the Crumbles, Daily Harvest suspected tara flour was the potential problem since the ingredient was unique to this product (it had never been used in any other product sold by Daily Harvest). Compellingly, similar adverse health events were reported for consumption of the Revive Superfoods (Oakville, ON, Canada) Mango and Pineapple smoothies which also contain tara protein as an ingredient. 

Tara flour is a new plant-based protein ingredient manufactured from the seeds of the South American tree Tara spinosa (Feuillé ex Molina) Britton & Rose (synonym: Caesalpinia spinosa (Molina) Kuntze) which is one of the three accepted species in the genus Tara (Legumino- sae). Tara spinosa is primarily cultivated in Peru (responsible for >80% of the world supply) as a rich source of tannins based on a galloyl quinic acid structure. Tara pods (without seeds) represent approximately 65% (by mass) of the fruit and are rich in hydrolyzable tannins (between 40−60% by mass), which are used mainly for the industrial production of tannins, while the seeds are used as a source of gum. 

In summary, the results of these initial studies support a working hypothesis that the adverse events reported by individuals consuming the Daily Harvest Crumbles product originate from the tara flour ingredient and are due, at least in part, to high levels of nonprotein amino acids (e.g., baikiain). It is further hypothesized that in vivo metabolism of metabolically unstable baikiain results in a toxic metabolite(s) that depletes glutathione and/or is an irreversible enzyme inhibitor (for L- pipecolate oxidase), resulting in adverse events which are dependent on the dose consumed and potentially exacerbated for individuals that have specific genetic predispositions. 

Here is the link to the full article:

The San Luis Obispo Tribune reports that an outbreak of norovirus stemming from a North County restaurant has sickened close to 100 people, according to the San Luis Obispo County Public Health Department. SLO County Public Health Epidemiologist Jessie Burmester said 97 people have been reported sick as part of a confirmed norovirus outbreak earlier this month. “When we perform our investigations, we’re really looking for a common source or exposure point,” she said. “Individuals have provided the name of the restaurant consistently for all the individuals that have reported on behalf of the 97 people so far.”

If I owned a restaurant in Paso Robles that was not the link in the Norovirus outbreak, I think I would be pissed.

Well, for whatever the reason the SLO County Public Heath authorities are remaining quiet as is the local media. So, here is what you need to know during an outbreak.

The Centers for Disease Control and Prevention (CDC) estimates that noroviruses cause nearly 21 million cases of acute gastroenteritis annually, making noroviruses the leading cause of gastroenteritis in adults in the United States. 

Nature has created an ingenious bug in norovirus. The round blue ball structure of norovirus is a protein surrounding the virus’s genetic material. The virus attaches to the outside of cells lining the intestine, and then transfers its genetic material into those cells. Once the genetic material has been transferred, norovirus reproduces, finally killing the human cells and releasing new copies of itself that attach to more cells of the intestine’s lining.

Humans are the only host of norovirus, and norovirus has several mechanisms that allow it to spread quickly and easily. Norovirus infects humans in a pathway like the influenza virus’ mode of infection. In addition to their similar infective pathways, norovirus and influenza also evolve to avoid the immune system in a similar way. Both viruses are driven by heavy immune selection pressure and antigenic drift, allowing evasion of the immune system, which results in outbreaks. Norovirus can survive a wide range of temperatures and in many different environments. Moreover, the viruses can spread quickly, especially in places where people are in proximity, such as cruise ships and airline flights, even those of short duration.

Norovirus causes nearly 60% of all foodborne illness outbreaks. Norovirus is transmitted primarily through the fecal-oral route, with fewer than 100 norovirus particles needed to cause infection. Transmission occurs either person-to-person or through contamination of food or water. CDC statistics show that food is the most common vehicle of transmission for noroviruses; of 232 outbreaks of norovirus between July 1997 and June 2000, 57% were foodborne, 16% were spread from person-to-person, and 3% were waterborne. When food is the vehicle of transmission, contamination occurs most often through a food handler improperly handling a food directly before it is eaten. 

Infected individuals shed the virus in large numbers in their vomit and stool, shedding the highest number of viral particles while they are ill. Aerosolized vomit has also been implicated as a mode of norovirus transmission. Previously, it was thought that viral shedding ceased approximately 100 hours after infection; however, some individuals continue to shed norovirus long after they have recovered from it, in some cases up to 28 days after experiencing symptoms. Viral shedding can also precede symptoms, which occurs in approximately 30% of cases. Often, an infected food handler may not even show symptoms. In these cases, people can carry the same viral load as those who do experience symptoms.

Norovirus illness usually develops 24 to 48 hours after ingestion of contaminated food or water. Symptoms typically last a relatively short amount of time, approximately 24 to 48 hours. These symptoms include nausea, vomiting, diarrhea, and abdominal pain.  Headache and low-grade fever may also accompany this illness. People infected with norovirus usually recover in two to three days without serious or long-term health effects.

Although symptoms usually only last one to two days in healthy individuals, norovirus infection can become quite serious in children, the elderly, and immune-compromised individuals. In some cases, severe dehydration, malnutrition, and even death can result from norovirus infection, especially among children and among older and immune-compromised adults in hospitals and nursing homes. Recently, there have been reports of some long-term effects associated with norovirus, including necrotizing entercolitis, chronic diarrhea, and post-infectious irritable bowel syndrome, but more data is needed to support these claims.

Proper hand washing is the best way to prevent the spread of norovirus.

  1. American Public Health Association (APHA), Heymann, David L., editor, “Norovirus Infection,” in CONTROL OF COMMUNICABLE DISEASES MANUAL, pp. 227-29, (18th Ed. 2008).
  2. Antonio, J, et al., “Passenger Behaviors During Norovirus Outbreaks on Cruise Ships,” INTERNATIONAL SOCIETY OF TRAVEL MAGAZINE, Vol. 15, No. 3, pp. 172-176 (May-June 2008). Abstract available online at
  3. Benson, V. and Merano, M.A., “Current estimates from the National Health Interview Survey 1995,” VITAL HEALTH STATISTICS, SERIES 10 (Nat’l Center for Health Statistics 1998). Abstract available online at
  4. Cáceres, VM, et al., “A viral gastroenteritis outbreak associated with person-to-person spread among hospital staff,” INFECTION CONTROL AND HOSPITAL EPIDEMIOLOGY, Vol. 19, No. 3, pp. 162-7 (March 1998). Abstract available online at
  5. CDC, Norovirus:  Technical Fact Sheet, from Centers for Disease Control and Prevention Web site, (last modified on August 24, 2011) (last checked on Jan. 3, 2012). 
  6. CDC, Norovirus in Healthcare Facilities Fact Sheet, released December 21, 2006, available through Centers for Disease Control and Prevention website, at (last checked on January 4, 2012).
  7. CDC, Facts about Norovirus on Cruise Ships, last updated July 20, 2009, available through the Centers for Disease Control and Prevention website, at (last checked on January 4, 2012). 
  8. CDC, “Outbreaks of Gastroenteritis Associated with Noroviruses on Cruise Ships – United States, 2002,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 51, No. 49, pp. 1112-15 (Dec. 13, 2002). Full text available online at
  9. CDC, “Updated Norovirus Outbreak Management and Disease Prevention Guidelines,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 60, Recommendations and Reports No. 3, pp. 1-15 (March 4, 2011). Full text available online at
  10. CDC, “Norwalk-like viruses’—Public health consequences and outbreak management,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 50, Recommendations and Reports No. 9, pp. 1-18 (June 1, 2001). Full text available online at
  11. Duizer, E, et al., “Probabilities in norovirus outbreak diagnosis,” JOURNAL OF CLINICAL VIROLOGY, Vol. 40, No. 1, pp. 38-42 (Sept. 2007). Abstract available online at
  12. Donaldson, E., et al., “Viral shape-shifting: norovirus evasion of the human immune system,” NATURE REVIEWS, MICROBIOLOGY, Vol. 8, No. 3, pp. 231-239 (March 2010). Abstract available online at
  13. Fankhauser, RL, et al., “Epidemiologic and molecular trends of ‘Norwalk-like viruses’ associated with outbreaks of gastroenteritis in the United States,” JOURNAL OF INFECTIOUS DISEASES, Vol.186, No. 1, pp. 1-7 (July 1, 2002). Full text of article available online at
  14. Gerencher, Christine L., Reporter, “Understanding How Disease Is Transmitted via Air Travel: Summary of a Symposium,” Conference Proceedings 47, Transportation Research Board of the National Academies (2010). Full summary available online at
  15. Glass, RI, et al., “The Epidemiology of Enteric Caliciviruses from Humans: A Reassessment Using New Diagnostics,” JOURNAL OF INFECTIOUS DISEASES, Vol. 181, Supplement 2, pp. S254-61 (2000). Full text available online at
  16. Glass, R, Parashar, U.D., and Estes, M.K., “Norovirus Gastroenteritis,” NEW ENGLAND JOURNAL OF MEDICINE, Vol. 361, No. 18, pp. 1776-1785 (Oct. 29, 2009). Full text available online at
  17. Janneke, C, et al., “Enhanced Hygiene Measures and Norovirus Transmission during an Outbreak,” EMERGING INFECTIOUS DISEASES, Vol. 15, No., pp. 24-30 (Jan. 2009). Full text available online at
  18. Harris, JP, et al., “Deaths from Norovirus among the Elderly, England and Wales,” EMERGING INFECTIOUS DISEASES, Vol. 14, No. 10, pp. 1548-1552 (Oct. 2008). Full text available online at
  19. Kirkland, KB, et al., “Steaming oysters does not prevent Norwalk-like gastroenteritis,” PUBLIC HEALTH REPORTS, Vol. 111, pp. 527-30 (1996). Full text available online at
  20. Maunula, L, Miettinen, IT, and Bonsdorff, CH, “Norovirus Outbreaks from Drinking Water,” EMERGING INFECTIOUS DISEASES, Vol. 11, No. 11, pp. 1716-1721 (2005).  Full text available online at
  21. Lopman, Ben, Zambon, Maria, and Brown, David, “The Evolution of Norovirus, the ‘Gastric Flu,’” Public Library of Science: Medicine, Vol. 5, Issue 2, pp.187-189 (Feb. 2010). Full text available online at
  22. Lowther, J, Henshilwood, K, and Lees DN, “Determination of Norovirus Contamination in Oysters from Two Commercial Harvesting Areas over an Extended Period, Using Semiquantitative Real-Time Reverse Transcription PCR,” JOURNAL OF FOOD PROTECTION, Vol. 71, No. 7, pp. 1427-1433 (2008). Abstract available online at
  23. Lysen, M, et al., “Genetic Diversity among Food-Borne and Waterborne Norovirus Strains Causing Outbreaks in Sweden,” JOURNAL OF CLINICAL MICROBIOLOGY, Vol. 47, No. 8, pp. 2411-2418 (2009). Full text available online at
  24. Marks, PJ, et al., “Evidence of airborne transmission of Norwalk-like virus (NLV) in a hotel restaurant,” EPIDEMIOLOGY AND INFECTION, Vol. 124, No. 3, pp. 481-87 (June 2000). Full text available online at
  25. Mayo Clinic, “Norovirus Infection,” Mayo Clinic Web site, information last updated April 15, 2011 (as of last checking on Jan. 3, 2012), available online at
  26. Mead, Paul M, et al., “Food-related Illness and Death in the United States,” EMERGING INFECTIOUS DISEASES, Vol. 5, No. 5, pp. 607-25 (September-October 1999). Full text available online at
  27. Middleton, PJ, Szmanski, MT, and Petric M, “Viruses associated with acute gastroenteritis in young children,” AMERICAN JOURNAL OF DISEASES OF CHILDREN, Vol. 131, No. 7, pp. 733-37 (July 1977). Abstract available online at
  28. Patterson, T, Hutchin, P, and Palmer S, “Outbreak of SRSV gastroenteritis at an international conference traced to food handled by a post symptomatic caterer,” EPIDEMIOLOGY AND INFECTION,  Vol. 111, No. 1, pp. 157-162 (Aug. 1993). Available online at
  29. Ozawa, K, et al., “Norovirus Infections in Symptomatic and Asymptomatic Food Handlers in Japan,” JOURNAL OF CLINICAL MICROBIOLOGY, Vol. 45, No. 12, pp. 3996-4005 (Oct. 2007). Abstract available online at
  30. Said, Maria, Perl, Trish, and Sears Cynthia, “Gastrointestinal Flu: Norovirus in Health Care and Long-Term Care Facilities,” HEALTHCARE EPIDEMIOLOGY, vol. 47, pp. 1202-1208 (Nov. 1, 2008). Full text available online at
  31. Scallan, E., et al., “Foodborne Illness Acquired in the United States—Major Pathogens,” EMERGING INFECTIOUS DISEASES, Vol. 17, No. 1, pp. 7-15 (2011). Full text available online at
  32. Siebenga, JJ, et al., “Norovirus Illness Is a Global Problem: Emergence and Spread of Norovirus GII.4 Variants, 2001–2007,” JOURNAL OF INFECTIOUS DISEASES, Vol. 200, No. 5, pp. 802-812 (2009). Full text available online at
  33. Treanor, John J. and Dolin, Raphael, “Norwalk Virus and Other Calciviruses,” in Mandell, Douglas, and Bennett’s PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASES, Fifth Edition, Chap. 163, pp. 1949-56 (2000, Mandell, Bennett, and Dolan, Editors).
  34. Tu, E.T., et al., “Epidemics of Gastroenteritis during 2006 Were Associated with the Spread of Norovirus GII.4 Variants 2006a and 2006b,” CLINICAL INFECTIOUS DISEASES, Vol. 46, No. 3, pp. 413-420 (Feb. 1, 2008). Full text available online at
  35. Tu E.T., et al., “Norovirus excretion in an age-care setting,” JOURNAL OF CLINICAL MICROBIOLOGY, Vol. 46, pp. 2119-21 (June 2008). Full text available online at
  36. Verhoef, L, et al., “Emergence of New Norovirus Variants on Spring Cruise Ships and Prediction of Winter Epidemics,” EMERGING INFECTIOUS DISEASES, Vol. 14, No. 2, pp. 238-243 (Feb. 2008). Full text available online at
  37. Vinje, J, “A Norovirus Vaccine on the Horizon?” EMERGING INFECTIOUS DISEASES, Vol. 202, No. 11, pp. 1623-1625 (2010). Full text available online at
  38. Westrell T, et al., “Norovirus outbreaks linked to oyster consumption in the United Kingdom, Norway, France, Sweden and Denmark,”  EURO-SURVEILLANCE (European Communicable Disease Bulletin), Vol. 15, No. 12 (Mar. 25, 2010). Full text available online at

Too bad the Taco Bell worker was not already vaccinated.

The Snohomish County Health Department has identified a case of hepatitis A that occurred in a food worker who worked at two Taco Bell locations: 2727 Broadway in Everett and 303 91st Ave NE in Lake Stevens.

Anyone who ate food from the Everett location on May 22 or 23 or from the Lake Stevens location on May 23 should take the following actions:

  • Check if they are vaccinated against or immune to hepatitis A. People who are vaccinated or immune do not need to take any further action as they would be considered protected against this exposure. People can check their vaccination records by contacting their healthcare provider, using the Washington Immunization Information System at or, if available, referring to their copy of their immunization record. People who have previously been infected with hepatitis A also may be immune. If they are not sure, they should check with their healthcare provider. 

Hepatitis A vaccine should be administered as soon as possible, within 2 weeks of exposure, to all unvaccinated people aged ≥12 months who have recently been exposed to hepatitis A virus (HAV).

It is surprising the the Hepatitis A vaccines are not being offered to all exposed patrons by the Snohomish Department of Health.

According to the CDC and FDA, as of May 23, 2023, 18 people infected with the outbreak strain of Salmonella Enteritidis have been reported in Washington, Oregon, California, Idaho, Utah and Missouri. Illnesses started on dates ranging from February 27, 2023, to May 2, 2023.

The CDC and FDA have determined that the likely food products implicated are Papa Murphy’s Take ‘N’ Bake raw Chocolate Chip Cookie and S’mores Bars dough.

Papa Murphy’s has temporarily stopped selling their raw chocolate chip cookie dough and raw S’mores bars dough. CDC is advising people to check their refrigerator and freezer for these raw doughs and to throw any away. CDC always advises people not to eat raw cookie dough, unless it has a label indicating that it is safe to be eaten raw.

Why no recall?

Investigators are working to identify the contaminated ingredient in the raw cookie dough.

Cookie Dough Mix [Enriched Bleached Flour (Wheat Flour, Niacin, Reduced Iron, Thiamine Mononitrate, Riboflavin, Folic Acid), Sugar, Eggs (Dried & Pasteurized), Leavening (Sodium Bicarbonate, Sodium Aluminum Phosphate), Canola or Soybean Oil, Salt, Egg Whites (Dried & Pasteurized), Natural and Artificial Flavors], Water, Margarine [Palm Oil, Palm Kernel Oil, Canola Oil, Water, Salt, Whey Powder (Milk), Vegetable Monoglycerides, Soybean Lecithin, Potassium Sorbate, (Preservative), Citric Acid, Artificial Flavor, Vitamin A Palmitate, Colored with Beta-Carotene, Vitamin D3], Semi-Sweet Chips {Sugar, Unsweetened Chocolate, Cocoa Butter, Soy Lecithin (an emulsifier), Natural Vanilla Extract}, Brown Sugar.

So, what ingredient was the tainted one?

The eggs? The flour?

The Snohomish County Health Department has identified a case of hepatitis A that occurred in a food worker who worked at two Taco Bell locations: 2727 Broadway in Everett and 303 91st Ave NE in Lake Stevens

Anyone who ate food from the Everett location on May 22 or 23 or from the Lake Stevens location on May 23 should take the following actions:

Check if they are vaccinated against or immune to hepatitis A. People who are vaccinated or immune do not need to take any further action as they would be considered protected against this exposure. People can check their vaccination records by contacting their healthcare provider, using the Washington Immunization Information System at or, if available, referring to their copy of their immunization record. People who have previously been infected with hepatitis A also may be immune. If they are not sure, they should check with their healthcare provider.

Individuals who are not vaccinated, immune, or are unsure of their status should: 

Contact their healthcare provider or contact the Snohomish County Health Department at 425-339-3503 (then press 1) for guidance and potential post-exposure prophylaxis to prevent illness. Post-exposure prophylaxis involves receiving the hep A vaccine or immune globulin (IG), which can provide immediate and lasting protection when given within two weeks of exposure to the hepatitis A virus. Hepatitis A vaccine is available from multiple healthcare providers or pharmacies in the county. Anyone who was exposed and is having trouble finding a vaccine provider, or who is uninsured or underinsured, should contact the Health Department. 

Monitor for any symptoms of illness. Stay home and do not prepare or serve food for others if you have symptoms. It takes between 15 and 50 days to become symptomatic after being exposed.

Early signs of hepatitis A include:
• fever
• fatigue
• loss of appetite
• nausea
• vomiting
• diarrhea
• dark urine and jaundice (yellowing of eyes or skin)

If you develop any of these symptoms, be especially thorough in handwashing after using the restroom and before preparing or handling food to avoid potentially spreading the illness further. Wash hands with soap and running water. Be sure to lather and scrub all surfaces including backs of the hands, wrists, between fingers, and under fingernails. 

The confirmed case appears to have been infected during international travel. The Snohomish County Health Department is working with the business to identify other workers who were potentially exposed and connect them with prevention information as well as resources for vaccination and post-exposure prophylaxis, as needed.

Why this continues to happen is beyond me. Here is a letter I wrote not too long ago:

ACIP Secretariat
Advisory Committee on Immunization Practices 
1600 Clifton Road, N.E., Mailstop H24-8
Atlanta, GA 30329-4027

Re:  Letter to the CDC’s Committee on Immunization Practices – It is time to deal with Hepatitis A and Food Service Workers

Dear ACIP Secretariat:

The Advisory Committee on Immunization Practices (ACIP) provides advice and guidance to the Director of the CDC regarding use of vaccines and related agents for control of vaccine-preventable diseases in the civilian population of the United States. Recommendations made by the ACIP are reviewed by the CDC Director and, if adopted, are published as official CDC/HHS recommendations in the Morbidity and Mortality Weekly Report (MMWR).

Presently, approximately 5% of all hepatitis A outbreaks are linked to infected food-handlers.

Here is what the CDC continues to say about vaccinating food-handlers:

Why does CDC not recommend all food handlers be vaccinated if an infected food handler can spread disease during outbreaks?

CDC does not recommend vaccinating all food handlers because doing so would not prevent or stop the ongoing outbreaks primarily affecting individuals who report using or injecting drugs and people experiencing homelessness. Food handlers are not at increased risk for hepatitis A because of their occupation. During ongoing outbreaks, transmission from food handlers to restaurant patrons has been extremely rare because standard sanitation practices of food handlers help prevent the spread of the virus. Individuals who live in a household with an infected person or who participate in risk behaviors previously described are at greater risk for hepatitis A infection.

The CDC misses the point; granted, food service workers are not more at risk of getting hepatitis A because of their occupation, but they are a risk for spreading it to customers. Food service positions are typically low paying, and certainly have the likelihood of being filled by people who are immigrants from countries where hepatitis A might be endemic or by people who have been recently experienced homelessness.

Over the past several years, there has been an ongoing outbreak of hepatitis A in the United States. As of February 2, 2023, there have been a total of 44,779 cases with a 61% hospitalization rate (approximately 27,342 hospitalizations). The death toll stands at 421. Since the outbreak started in 2016, 37 states have reported cases to the CDC.

The CDC recommends to the public that the best way to prevent hepatitis A is through vaccination, but the CDC has not explicitly stated that food service workers should be administered the vaccination. While food service workers are not traditionally designated as having an increased risk of hepatitis A transmission, they are not free from risk. 

24% of hepatitis A cases are asymptomatic, which means a food-handler carrying the virus can unknowingly transmit the disease to consumers. Historically, when an outbreak occurs, local health departments start administering the vaccine for free or at a reduced cost. The funding from these vaccinations is through taxpayer dollars. 

A mandatory vaccination policy for all food service workers was shown to be effective at reducing infections and economic burden in St. Louis County, Missouri.

From 1996 to 2003, Clark Country, Nevada had 1,523 confirmed cases of hepatitis A, which was higher than the national average. Due to these alarming rates, Clark County implemented a mandatory vaccination policy for food service workers. As a result, in 2000, the hepatitis A rates significantly dropped and reached historic lows in 2010. The county removed the mandatory vaccine rule in 2012 and are now part of the ongoing hepatitis A outbreak. 

According to the CDC, the vaccinations cost anywhere from $30 to $120 to administer, compared to thousands of dollars in hospital bills, and offer a 95% efficacy rate after the first dose and a 99% efficacy after the second dose. Furthermore, the vaccine retains its efficacy for 15-20 years.  

During an outbreak, if a food service worker is found to be hepatitis A positive, a local health department will initiate post-exposure treatment plans that must be administered within a two-week period to be effective. The economic burden also affects the health department in terms of personnel and other limited resources. Sometimes, the interventions implemented by the local health department may be ineffective. 

Though there are many examples of point-source outbreaks of hepatitis A that have occurred within the past few years around the country, a particularly egregious outbreak occurred in the early fall of 2021 in Roanoke, Virginia. The health department was notified about the outbreak on September 21, 2021, after the first case was reported by a local hospital. The Roanoke Health Department, along with the Virginia Department of Health, investigated this outbreak.

Three different locations of a local restaurant, Famous Anthony’s, were ultimately determined to be associated with this outbreak. The Virginia Department of Health published a community announcement on September 24, 2021, about the outbreak and the potential exposure risk. 

For purposes of the investigation, a case was defined as a “[p]erson with (a) discrete onset of symptoms and (b) jaundice or elevated serum aminotransferase levels and (c) [who] tested positive for hepatitis A (IgM anti-HAV-positive), and frequented any of three Famous Anthony’s locations, or was a close contact to the index case patient, during the dates of August 10 through August 27, 2021.”

As of November 2021, a total of 49 primary cases (40 confirmed and 9 probable) were identified in this outbreak. Two secondary cases were also identified. Cases ranged from 30 to 82 years of age (median age of 63). In all, 57 percent of cases were male. Thirty-one cases included hospitalizations, and at least 4 case patients died. Illness onsets occurred between August 25 and October 15, 2021.

Ultimately, the outbreak investigation revealed that a cook, who also had risk factors associated with hepatitis A, had been infected with hepatitis A while working at multiple Famous Anthony’s restaurant locations. This index case’s mother and adult son also tested positive for hepatitis A. Following an inspection, the outbreak inspector noted, “due to the etiology of hepatitis A transmission, it is assumed the infectious food handler did not perform proper hand washing or follow glove use policy.” It was determined that person-to-person spread was the most likely mode of transmission in this outbreak. Environmental contamination was also considered a possible mode of transmission. 

Overwhelmed by the number of victims who pursued legal action for their injuries, Famous Anthony’s filed for bankruptcy and several of its locations have been closed.

The tragedy of this preventable hepatitis A outbreak cannot be overstated. Four people died. In one family, two of its members lost their lives. Most of the victims were hospitalized. Many risked acute liver failures. At least one person required both a liver and kidney transplants. Medical bills for the victims totaled over $6,000,000 in acute costs with millions of dollars in future expenses. And this all because one employee did not receive a $30-$120 hepatitis A vaccine.

Affordable prevention of future tragedies like the Famous Anthony’s outbreak is possible and necessary. The time has come to at least recommend vaccinations to food service workers to reduce the spread of hepatitis A.

Bill Marler
On behalf of 31 hepatitis A victims and families

1 Privately, via mail, I am providing medical summaries for 31 of the victims so there can be a clear assessment of the impacts of hepatitis A on consumers of food at the hands of one unvaccinated food service worker.

I must admit, in 30 years of doing food safety, I seldom recall a health department withholding from the public the source of an outbreak – even Norovirus.

I am reminded by a story some 10 years ago – After Food Safety News broke the story that Taco Bell was the mysterious “Restaurant Chain A” linked to a Salmonella outbreak that sickened 68 people in 10 states, ABC Evening News praised Food Safety News for shining light on this story and the issue of the government’s lack of transparency when businesses make people sick.  Other media, such as the LA Times, Reuters, Daily Mail, The Consumerist, CBS News,Huffington Post, Fox News, and MSNBC, also hailed Food Safety News for shinning the light on the mystery taco restaurant.  Most recently, Barry Estabrook wrote a piece for The Atlantic detailing Food Safety New’s muckraking skills, but praised me and not the people who did all the work.

The San Luis Obispo Tribune reports that an outbreak of norovirus stemming from a North County restaurant has sickened close to 100 people, according to the San Luis Obispo County Public Health Department. SLO County Public Health Epidemiologist Jessie Burmester said 97 people have been reported sick as part of a confirmed norovirus outbreak earlier this month. Burmester said the Public Health Department traced the “unusual, very large community outbreak” back to a North County restaurant, though she did not disclose the name of the business.

“When we perform our investigations, we’re really looking for a common source or exposure point,” she said. “Individuals have provided the name of the restaurant consistently for all the individuals that have reported on behalf of the 97 people so far.” Burmester said the Public Health Department reached its threshold for an outbreak — two reported cases in separate households — on May 15. That day, the agency received more than two reports about the same exposure source, she said. Follow-up investigation showed some people experiencing symptoms of norovirus tied to that facility as early as May 11, Burmester added.

Once it was identified, the Public Health Department began working to help eliminate further spread by pushing “mass cleaning and disinfection” of the restaurant, as well as attempting to track where the cases originated. The restaurant in question has been cleaned three times since the outbreak was first reported, she said. “This has been particularly challenging outbreak,” Burmester said, “but it is not abnormal to see norovirus spread like this, because it doesn’t take much of the virus to spread at all.”

Norovirus is a nasty bug.

Noroviruses are estimated to cause 23 million cases of acute gastroenteritis (commonly called the “stomach flu”) in the U.S. each year, and are the leading cause of gastroenteritis. In addition, norovirus outbreaks may be the most common foodborne illness outbreaks. Noroviruses can cause extended outbreaks because of their high infectivity, persistence in the environment, resistance to common disinfectants, and difficulty in controlling their transmission through routine sanitary measures.

The norovirus is transmitted primarily through the fecal-oral route and fewer than 100 norovirus particles are said to be needed to cause infection. Transmission occurs either person-to-person or through contamination of food or water. Transmission can occur by:

· Touching surfaces or objects contaminated with norovirus and then placing that hand in your mouth

· Having direct contact with another person who is infected with norovirus and showing symptoms

· Sharing foods or eating utensils with someone who is ill

· Exposure to aerosolized vomit

· Consuming food contaminated by an infected food handler.

Boston health inspectors ordered the closure of a Brighton restaurant and suspended the restaurant’s permit to operate after foodborne illnesses were reported and an inspection identified multiple problems this week. Los Amigos Taqueria at 366 Washington St. in Brighton was ordered to close on Thursday. 

The Boston Public Health Commission confirmed that it is investigating “an emerging salmonella outbreak” linked to the restaurant. 

According to a city database, one of six identified failures included “multiple reports of a foodborne illness from items consumed at this location.”

Inspectors took samples of the food from the restaurant and instructed the business not to handle any food without approval from city health officials, the database shows. 

Additional issues identified by the inspection at the Brighton location included “visible soils and mold-like substance” found in a walk-in unit; shelving units with visible rust and soils; and a lack of proper sanitizers at work and prep stations. The restaurant at 1741 Centre St. in West Roxbury had its permit to operate suspended after inspectors found issues including rodent droppings, foods kept outside of proper temperatures and staff members not following proper glove or hand washing procedures.

In Brighton, health inspectors said “There are multiple reports of a foodborne illness from items consumed at this location.” An inspection found “visible soils” and “mold like” substances in a walk-in unit.

At the West Roxbury restaurant on Centre Street, inspectors found “no verifiable evidence of illness policy training,” and no one was in charge of monitoring food temperatures. They said “only one employee properly washed hands between tasks,” and a spatula was found stored in stagnant water.

The inspection also discovered rodent waste in the restaurant.

“Multiple rodent droppings on pineapple cans, bag of pinto beans, beverage single use holders, on storage tables an floor,” the report stated.

Salmonella:  Marler Clark, The Food Safety Law Firm, is the nation’s leading law firm representing victims of Salmonella outbreaks. The Salmonella lawyers of Marler Clark have represented thousands of victims of Salmonella and other foodborne illness outbreaks and have recovered over $850 million for clients.  Marler Clark is the only law firm in the nation with a practice focused exclusively on foodborne illness litigation.  Our Salmonella lawyers have litigated Salmonella cases stemming from outbreaks traced to a variety of foods, such as cantaloupe, tomatoes, ground turkey, salami, sprouts, cereal, peanut butter, and food served in restaurants.  The law firm has brought Salmonella lawsuits against such companies as Cargill, ConAgra, Peanut Corporation of America, Sheetz, Taco Bell, Subway and Wal-Mart.  

If you or a family member became ill with a Salmonella infection, including Reactive Arthritis or Irritable bowel syndrome (IBS), after consuming food and you’re interested in pursuing a legal claim, contact the Marler Clark Salmonella attorneys for a free case evaluation.

Additional Resources:

The premiere of the Netflix Documentary, “Poisoned,” is a few weeks away (June 9) at the Tribeca Film Festival. We are thankful that the folks at Netflix are also allowing us to do a premiere night on Bainbridge Island on July 2. The small, historic Lynwood Theatre holds only about 250 people – but they sell local beer and wine. All tickets will be free and everyone will be asked to donate to our local food bank, Helpline House. The tickets will be available for reservation soon.

My new obsession, T-shirts will be available at the time of the movie premiere along with photos on the red carpet. Poisoned Books will be there for sale by Eagle Harbor Books, and signature by the author, Jeff Benedict. There will also be a special guest MC to do a short Q and A after the movie.

This is quite glam for Bainbridge Island.

For those that want a free T-shirt early, please send me an email with your mailing addressAFTER – you donate whatever you can to Helpline House. I am starting out with a seed gift of $5,000. Here is the link to donate – Thank you so much.

Here is the shirt in the package:

Here is the front:

Here is the back: