In late May 2014 John Napierski, purchased seven jars of VR Greens Farms (VRGF) Basil Pine Nut Pesto at a Farm Stand operated at the Bella Collina Towne and Golf Club in San Clemente, California.  While on a road trip east, Mr. Napierski gave two jars to friends in Denver, Colorado. He then continued his trip to Ohio and gave two jars to his daughter, Kathryn (“Katy”), who was a nursing student working and attending college in Cincinnati.  Katy and her friend, Arielle Allen, used a portion of one jar of pesto as an ingredient in a chicken pasta dish they cooked at home and shared on July 13. On July 15 Katy complained of a sore throat and difficulty swallowing. Arielle started to have similar symptoms on July 17.  Over the next ten days both women continued to experience neurological symptoms.  Both women had multiple medical encounters before botulism was suspected as the cause of their symptoms. Katy was admitted to Bethesda North Hospital on July 17 and transferred to the University of Cincinnati Medical Center on July 18. Arielle was admitted to the University of Cincinnati Medical Center on July 27 due to worsening bulbar and facial weakness. Arielle’s admission to the hospital prompted the attending neurologist to note her friendship with Katy and similarity in symptoms between the two women.  He diagnosed both Katy and Arielle as having suspected botulism and notified public health authorities. Botulism antitoxin was obtained from the Centers for Disease Control and Prevention (CDC) and administered to Arielle on the evening of July 28. Serum and stool collected from Arielle and Katy did not test positive for C. botulinum. The toxin, however, was found in pesto sauce leftover from the chicken pasta meal.

Investigators at the City of Cincinnati Health Department and the Ohio Department of Health quickly determined that Katy and Arielle had shared a meal of pasta with chicken and jarred pesto sauce. During a visit to Arielle’s apartment, investigators found leftover chicken pasta with pesto in the apartment refrigerator. This was collected for laboratory testing for the presence of Clostridium botulinum toxin as was an unopened jar of pesto that Katy had. On July 29 Ohio investigators notified the CDC, the Food and Drug Administration (FDA), and the California Department of Public Health (CDPH) Food and Drug Branch (FDB) that two Ohio residents had botulism and that the suspected source was VRGF Basil Pine Nut Pesto.  CDPH FDB contacted Dominic Romano, owner of VRGF, and informed him of the illnesses.

On July 30 California investigators conducted a site visit at the VRGF Farm Stand.  A variety of canned products were produced seasonally and sold at the farm location. Most of the products sold at the farm stand were produced at unregistered/unpermitted locations.  Mr. Romano was advised that he must immediately cease the unlicensed manufacturing and sale of low-acid canned and acidified foods.  A Notice of Violations was issued to Mr. Romano for lack of license/registration. The firm initiated a voluntary recall of all suspect low-acid canned and acidified foods.  The California Department of Public Health issued an alert on July 30 advising consumers to not eat VR Green Farms jarred products because of improper production making them susceptible to contamination with Clostridium botulinum.

California investigators learned that in April or May the pesto had been made by Rose Schwinn dba Rose’s Artesian Creations.  Ms. Schwinn was a family friend of Dominic Romano.  According to Mr. Romano only 10-12 jars were produced and were intended to be a test product.  This was later found to be inaccurate. On July 31 CDPH FDB investigator, Melissa DeHart, contacted Ms. Schwinn to discuss manufacturing processes. Ms. Schwinn reported that she manufactured the product in her home kitchen and that she had made small batches products sold at the Farm Stand “on and off for a few years.” She did not maintain a Processed Food Registration or a Cannery License with CDPH as required to manufacture these types of foods for retail sales.

Rose Schwinn described the process used to make the pesto sauce. Raw garlic cloves and salt were ground in the food processor. Fresh basil leaves and olive oil were added and then mixed with pine nuts and parmesan cheese. The ingredients were processed in small batches and added to one large pot due to limited size of the food processor. The product could sit for up to one hour at room temperature before it was filled into the jars.

New jars were cleaned by placing them in her household dishwasher on the hot cycle with dish detergent and bleach. The jars were then filled with water and place in the microwave until boiling. The lids were maintained in hot water until use. The ingredients were mixed together without a heat step to form a sauce and then filled into hot mason jars. Lids were applied and the jars were placed into a stove top water bath canning unit. The water in the canning unit was brought to a boil and the product was heated. A thermometer was not used. The jars were allowed to cool, the seal around the lid checked, and the product was labeled for distribution. The label did not include a complete ingredient statement, lot code, best by date, or a “Perishable Keep Refrigerated” statement.  CDPH FDB described the manufacturing process to be conducted under “insanitary conditions at a home residence.”

The CDPH Food and Drug Laboratory Branch (FDLB) collected an unopened jar of VRGF Basil Pine Nut Pesto from Rose Schwinn. The sample was tested for pH, water activity, and Elisa screening for C. botulinum.  Test results showed for sample #062080514, the pH was 5.3 and water activity was 0.965. Non-refrigerated foods that are packed in hermetically sealed jars with a pH above 4.6 and water activity above 0.85 are at risk for supporting C. botulinum toxin formation and must be manufactured in accordance with an approved scheduled process, controls and in California pursuant to a Cannery License.  Clearly, VRGF Basil Pine Nut Pesto did not meet the minimum requirements for food safety. Investigators determined that VRGF Basil Pine Nut Pesto placed “consumers of the product at risk for C. botulinum toxin illness.”

State public health laboratories in Ohio and California tested several samples of the pesto.  The Ohio Department of Health Bureau of Public Health Laboratories tested an unopened jar collected from Katy as well as leftover chicken pasta with pesto found in Arielle’s apartment. The left over pasta meal was positive for Clostridium botulinum toxin type B.  The unopened jar of pesto sauce tested negative for Clostridium botulinum toxins. Of the two jars that had been dropped off in Colorado, one jar had been consumed with no ill effects. The second jar had a swollen lid and was shipped to Ohio for C. botulinum testing. This jar also tested negative for C. botulinum toxins.  CDPH FDLB also tested an unopened jar of pesto collected from John Napierski.  This jar showed low levels of C. botulinum toxin B by Luminex system testing and “borderline” testing results by Elisa but definitive testing by the mouse bioassay was negative.

BOTULISM—A Rare, But Deadly Disease

Botulism is a rare, life-threatening paralytic illness caused by neurotoxins produced by an anaerobic, gram-positive, spore-forming bacterium, Clostridium botulinum.[1]  Unlike Clostridium perfringens, which requires the ingestion of large numbers of viable cells to cause symptoms, the symptoms of botulism are caused by the ingestion of highly toxic, soluble exotoxins produced by C. botulinum while growing in foods.[2]  These rod-shaped bacteria grow best under anaerobic (or, low oxygen), low-salt, and low-acid conditions.[3]  Bacterial growth is inhibited by refrigeration below 4° C., heating above 121° C, and high water-activity or acidity.[4]  And although the toxin is destroyed by heating to 85° C. for at least five minutes, the spores formed by the bacteria are not inactivated unless the food is heated under high pressure to 121° C. for at least twenty minutes.[5]

C. botulinum bacteria and spores are widely distributed in nature, because they are indigenous to soils and waters.[6] They occur in both cultivated and forest soils, bottom sediment of streams, lakes, and coastal waters, in the intestinal tracts of fish and mammals, and in the gills and viscera of crabs and other shellfish.[7]

The incidence of foodborne botulism is extremely low.[8]  Nonetheless, the extreme danger posed by the bacteria has required that “intensive surveillance is maintained for botulism cases in the United States, and every case is treated as a public health emergency.”[9] This danger includes a mortality rate of up to 65% when victims are not treated immediately and properly.[10] Most of the botulism events[11] that are reported annually in the United States are associated with home-canned foods that have not been safely processed.[12]  Very occasionally, however, commercially- processed foods are implicated as the source of a botulism events, including sausages, beef stew, canned vegetables, and seafood products.[13]

Symptoms of Botulism

After their ingestion, botulinum neurotoxins are absorbed primarily in the duodenum and jejunum, and pass into the bloodstream and travel to synapses in the nervous system.[14] There, the neurotoxins cause flaccid paralysis by preventing the release of acetylcholine, a neurotransmitter, at neuromuscular junctions, thereby preventing motor-fiber stimulation.[15] The flaccid paralysis progresses symmetrically downward, usually starting with the eyes and face, then moving to the throat, chest, and extremities.[16] When the diaphragm and chest muscles become fully involved, respiration is inhibited and, unless the patient is ventilated, death from asphyxia results.[17]

Classic symptoms of botulism include nausea, vomiting, fatigue, dizziness, double vision, drooping eyelids, slurred speech, difficulty swallowing, dryness of skin, mouth, and throat, lack of fever, muscle weakness, and paralysis.[18]  Infants with botulism appear lethargic, feed poorly, are constipated, and have a weak cry and poor muscle tone.[19] Throughout all such symptoms, the victims are fully alert and the results of sensory examination are normal.[20]

In foodborne botulism cases, symptoms usually begin anywhere between 12 and 72 hours after the ingestion of toxin-containing food.[21]  Longer incubation periods—up to 10 days—are not unknown, however.  The duration of the illness is from 1 to 10 (or more) days, depending on host-resistance, the amount of toxin ingested, and other factors.[22]  Full recovery often takes from weeks to months.[23] And, as earlier indicated, mortality rate can be from 30% to 65%, with rates generally lower in European countries than in the United States.[24]

Detection and Treatment of Botulism

Although botulism can be diagnosed based on clinical symptoms, its differentiation from other diseases is often difficult—especially in the absence of other known persons affected by the condition.[25] Once suspected, the most direct and effective way to confirm the diagnosis of botulism in the laboratory is testing for the presence of the botulinum toxin in the serum, stool, or gastric secretions of the patient.[26]  The food consumed by the patient can also be tested for the presence of toxins.[27]  Currently, the most sensitive and widely used method for the detection of the toxins is the mouse neutralization test, which involves injecting serum into mice and looking for signs of botulism.[28]  This test typically takes 48 hours, while the direct culturing of specimens takes 5-7 days.[29] Some cases of botulism may go undiagnosed because symptoms are transient or mild, or are misdiagnosed as Guillain-Barre Syndrome.[30]

If diagnosed early, foodborne botulism can be treated with an antitoxin that blocks the action of toxin circulating in the blood.[31] This can prevent patients from worsening, but recovery still takes many weeks.[32] The mainstay of therapy is supportive treatment in intensive care, and mechanical ventilation in case of respiratory failure, which is common.[33]

Long-Term and Permanent Injury

Although a minority of botulism patients eventually recover their pre-infection health, the majority do not. For those who fully recover, the greatest improvement in muscle strength occurs in the first three months after the acute phase of illness.[34]  The outside limit for such improvement appears, however, to be one year.[35]  Consequently, physical limitations that still exist beyond the one-year mark are more probably than not permanent.  Recovery from acute botulism symptoms may also be followed by persistent psychological dysfunction that may require intervention.[36]

According to a recently-published study that tracked the long-term outcomes of 217 cases of botulism, a large majority of patients reported “significant health, functional, and psychosocial limitations that are likely the consequences of the illness.”[37]  These limitations included: fatigue, weakness, dizziness, dry mouth, and difficulty lifting things.  The victims also reported difficulty breathing caused by moderate exertions, such as walking or lifting heavy items.  They were also more likely to have limitations in vigorous activities, like running or playing sports, climbing up three flights of stairs, or carrying groceries. Summarizing its finding, the study concluded that:

Even several years after acute illness, patients who had botulism were more likely than control subjects to experience fatigue, generalized weakness, dizziness, dry mouth, difficulty lifting things, and difficulty breathing caused by moderate exertion….In addition, patients…reported worse overall psycho-social status than did control subjects, with patients being significantly less likely to report feeling happy, calm and peaceful, or full of pep.[38]

There is, as a result, no question that the damaging effects of botulism are life-long.


The canning process dates back to the late 18th century in France when the Emperor Napoleon Bonaparte, concerned about keeping his armies fed, offered a cash prize to whoever could develop a reliable method of food preservation. Nicholas Appert conceived the idea of preserving food in bottles, like wine. After fifteen years of experimentation, he realized if food is sufficiently heated and sealed in an airtight container, it will not spoil. More than fifty years later, Louis Pasteur provided the explanation for effectiveness of canning when he was able to demonstrate that the growth of microorganisms is the cause of food spoilage.[40]

An Englishman, Peter Durand, took the idea one step further and replaced the breakable glass bottles with cylindrical tinplate canisters (later shortened to “cans”). Durand did not can foods himself, but sold his patent to two other Englishmen, Bryan Donkin and John Hall, who set up a commercial canning factory.  By 1813, Donkin and Hall were busily producing their first canned goods for the British army, thus continuing the connection of canning to the military.

The basic principles of canning have not changed dramatically since Nicholas Appert and Peter Durand developed the process. Heat sufficient to destroy microorganisms is applied to foods packed into sealed, or “airtight” containers.  The canned foods are then heated under steam pressure at temperatures of 240-250°F (116-121°C). The amount of time needed for processing is different for each food, depending on the food’s acidity, density and ability to transfer heat.

Processing conditions are chosen and designed to be the minimum needed to ensure that the foods are made “commercially sterile,” while still retaining the greatest flavor and nutrition.[41] All canning-processes must first be approved by the U.S. Food and Drug Administration.[42] Once the cans are sealed and heat processed, the resulting canned food must maintain its high eating quality for more than two years and be safe to eat as long as the can is not damaged in any way.  Historically, commercially-canned food has a near-perfect track record, having caused only four outbreaks in over forty years.[43] The last outbreak occurred in 1974 and involved beef stew.[44]

[1]           See J. Sobel, et al., Foodborne Botulism in the United States, 1990-2000, Emerging Infectious Diseases, Vol. 10, No. 9, at 1606 (Sept. 2004).

[2]           James M. Jay, MODERN FOOD MICROBIOLOGY, 466 (6th Ed. 2000)

[3]           Id. at 469-71; see also Sobel, supra note 2, at 1606.

[4]           Sobel, supra note 2, at 1606.

[5]           Id.

[6]           Jay, supra note 3, at 467-69.  See also, generally H. Houschild, Clostridium Botulinum, in FOODBORNE BACTERIAL PATHOGENS, at 112-89  (M. Doyle Ed. 1989)

[7]           Jay, supra note 3, at 467-69.

[8]           Sobel, supra note 2, at 1607-09; Jay, supra note 3, at 472-76.

[9]           Sobel, supra note 2, at 1606-07 (also noting that the CDC maintains a 24-hour clinical consultation and emergency antitoxin release service).

[10]          Jay, supra note 3, at 474.

[11]          With botulism, the broader term “event” is used to encompass both outbreaks—i.e., two or more cases of botulism caused by a common-source, as well as individual (or sporadic) cases.

[12]          Sobel, supra note 2, at 1610; Jay, supra note 3, at 474.

[13]          Id.

[14]          Thomas P. Bleck, Clostridium botulinum (Botulism), in MANDELL, DOUGLAS AND BENNETT’S PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASE 2543, 2544 (5th ed. 2000).

[15]          Id.; Sobel, supra note 2, at 1606.

[16]          Bleck, supra note 15, at 2545; see also BOTULISM FACT SHEET, National Agricultural Bio-Security Center, Kansas State University, online at

[17]          Bleck, supra note 15, at 2545; Sobel, supra note 2, at 1606.

[18]          Sobel, supra note 2, at 1606; Jay, supra note 3, at 474.

[19]          Jay, supra note 3, at 476-77.

[20]          Sobel, supra note 2, at 1606.

[21]          Jay, supra note 3, at 474.

[22]          Id.

[23]          R. Shapiro, et al., Botulism in the United States: A Clinical and Epidemiologic Review, Ann. Intern. Med. 1998; 129:221-28.

[24]          Jay, supra note 3, at 474.

[25]          Bleck, supra note 15, at 2546 (noting that “botulism has a limited differential diagnosis”).

[26]          Sobel, supra note 2, at 1607; see also FDA/CFSAN Bad Bug Book, Clostridium Botulinum, available at

[27]          Id.

[28]          Bleck, supra note 15, at 2546.  See also, e.g. MMWWR, supra note 1, at 2 (“CDC detected botulinum toxin Type A by mouse bioassay in the man’s serum sample”).

[29]          Bad Bug Book, supra note at 25.

[30]          Sobel, supra note 2, at 1606; Shapiro, supra note 23, at 223.

[31]          Jay, supra note 3, at 474; Sobel, supra note 2, at 1606.

[32]          Id.; Bleck, supra note 15, at 2546-67.

[33]          Sobel, supra note 2, at 1606.

[34]          Bleck, supra note 15, at 2547. See also P. Wilcox, et al., Recovery of Ventilatory and Upper Airway Muscles and Exercise Performance After Type-A Botulism, Chest, 98:620-26 (1990); J. Mann, et al., Patient Recovery From Type-A Botulism: Morbidity Assessment Following a Large Outbreak, Am. J. Public Health, 71 (3):266-69 (Mar. 1981).

[35]          Id.

[36]          Bleck, supra note 15, at 2547. See also F. Cohen, et al., Physical and Psychosocial Health Status 3 Years After Catastrophic Illness—Botulism, Issues Mental Health Nurs., 9:387098 (1988)

[37]          S. Gottlieb, et al., Long-Term Outcomes of 217 Botulism Cases in the Republic of Georgia, Clin. Infectious Disease, 45: 174-80, at 180 (220&).

[38]          Id. at 179.

[39]          The following introductory material is based on information from the Wikipedia entry on canning, online at, and the sources there cited. See also Jay, supra note 2, a 4-5 (describing the events that lead to the discovery of canning).

[40]          Tony Baird-Packer, The Production of Microbiologically Safe and Stable Foods, in Volume 1 of THE MICROBIOLOGICAL SAFETY AND QUALITY OF FOOD, 4 (B. Lund, et al. Eds. 2000) (also noting that the manufacture of canned foods is “now more than a 300 billion dollar business worldwide”).

[41]          The term “commercial sterility” is used to describe the process endpoint of canned foods. Id. at 36.

[42]          See Thermally Processed Low-Acid Foods Packaged in Hermetically Sealed Containers, 21 CFR Part 113 and Acidified Foods, 21 CFR Part 114 (describing “requirements” for manufacturing, processing and packing foods “to prevent” an environment conducive to the growth of Clostridium botulinum).

[43]          Sobel, supra note 2, at 1609-10.

[44]          See, e.g. MMWWR, supra note 1, at 3 (citing P. Blake, et al., Type A Botulism from Commercially-Canned Beef Stew, South. Med. J. 1977; 70:5-7).