TMA's Committee on Infectious Diseases recommends physicians ask patients with symptoms of a foodborne illness if they have eaten cantaloupes recalled for contamination with Listeria monocytogenes. As of Oct. 11, 116 people in Texas and 24 other states were confirmed as infected with any one of four strains of L. monocytogenes. So far, the cases are linked to cantaloupes from the Jensen Farms in Colorado. Two of the 23 deaths reported from this outbreak were in Texas.
The U.S. Centers for Disease Control and Prevention (CDC) reports that this is the deadliest outbreak of foodborne illness in the United States in more than a decade.
The U.S. Food and Drug Administration recalled the cantaloupes from Jensen Farms on Sept. 14; however, the incubation period for sepsis due to Listeria is up to two months, so patients in Texas could still develop symptoms for several more weeks. The incubation period for gastroenteritis due to Listeria is generally less than one week, so stool cultures may no longer be necessary. If antibiotic therapy is indicated and the patient is allergic to penicillin, the committee recommends you consult with an infectious disease physician to determine the best treatment alternatives.
Exposure to L. monocytogenes is common and disease is rare, but some people are at increased risk, including pregnant women, people who are immunocompromised, and older adults. The committee recommends that patients use caution before consuming the fruit and to verify its source by the label and with the retailer. "When in doubt, throw it out" is the best policy.
The committee recommends you review the CDC-developed memorandum for the management of persons exposed to L. monocytogenes. This is intended to provide a framework for the management of patients exposed to L. monocytogenes and who are at increased risk for invasive listeriosis, including pregnant women. This is not intended to modify existing practices for managing a patient with confirmed or suspected listeriosis.
CDC's Diagnosis and Management of Foodborne Illnesses – A Primer for Physicians and Other Health Care Professionals
CDC's Listeriosis page with latest updates on multistate outbreak
Dallas County Health and Human Services advisory on listeriosis [PDF]
Action, Oct. 17, 2011