The CDC’s publication, Moribidity and Mortality Weekly Report (MMWR) released today includes a summary of the ConAgra peanut butter Salmonella outbreak investigation. The report states in part:

In February 2007, a case-control study with 65 patients and 124 controls was conducted to identify the food item associated with illness; the majority of interviews were completed by state and local health departments and were coordinated by CDC. For the study, a case was defined as infection with the outbreak strain of Salmonella Tennessee in a person aged >18 years with a history of diarrhea. Controls were well adults from the patient’s community who were matched by geographic location. Controls were identified using a reverse online telephone directory that when given an address provided telephone numbers for residences in the same extended neighborhood as the patients. The median ages for the patients and controls were 53 and 58 years, respectively. Patients were more likely than controls to have eaten peanut butter (81% versus 65%, matched odds ratio [mOR] = 1.9, 95% confidence interval [CI] = 0.8–5.2), to have eaten peanut butter more than once a week (66% versus 40%, mOR = 3.5, CI = 1.4–9.9), and to have eaten either Peter Pan or Great Value peanut butter (67% versus 13%, mOR = 10.9, CI = 3.8–43.0). Neither the consumption of other peanut butter brands nor consumption of turkey products was associated with illness.

Epidemiologic data suggesting Peter Pan brands of peanut butter as the possible source of the outbreak were provided to FDA officials on February 13, 2007. The following day, FDA issued a health alert to consumers indicating that they should not eat Peter Pan or Great Value peanut butter with a product code beginning with 2111, both of which were manufactured in a single facility in Georgia operated by ConAgra Foods. ConAgra Foods voluntarily recalled the products, destroyed existing products in their possession, and temporarily halted production pending further investigation.

We are continuing our own investigation into nearly 5,000 claims of illness after eating the peanut butter.