Fresh crab meat imported from the failed state of Venezuela caused 26 consumers in eight U.S. jurisdictions to suffer from Vibrio parahaemolyticus infections between April 1 and July 19 of this year, but the outbreaks over now.
Vibrio parahaemolyticus is a curved, rod-shaped, Gram-negative bacterium found in brackish, saltwater, which, when ingested, causes gastrointestinal illness in humans.
The U.S. Vibrio outbreak occurred as Venezuela’s economy continued in a complete freefall. Most Venezuelan government services hardly exist. A recent BBC report said hyperinflation, power cuts, and food and medicine shortages are driving millions of Venezuelans out of the country that was once the wealthiest in all of Latin America.
The federal Centers for Disease Control and Prevention (CDC) in Atlanta says the outbreak is now over but warned about Vibrio as “an important cause of illness in the United States.”
The U.S. Food and Drug Administration found “fresh” or “pre-cooked” labels on the ready-to-eat Venezuelan crab meat. Epidemiologic, traceback, and laboratory evidence all pointed to the Venezuelan fresh crab meat as the likely source of the outbreak. Vibrio parahaemolyticus is a bacterium in the same family as those that cause cholera.
CDC said public health investigators used the PulseNet system to help identify illnesses that might have been part of this outbreak. PulseNet is the national subtyping network of public health and food regulatory agency laboratories coordinated by CDC.
Investigators performed DNA on Vibrio bacteria isolated from ill people by using techniques called pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). CDC PulseNet manages a national database of these DNA fingerprints to identify possible outbreaks. WGS gives a more detailed DNA fingerprint than PFGE.
Those with the Vibrio illnesses in the outbreak ranged in age from 26 to 78 years, with a median age of 55. Among ill people, 54 percent are male. Among people with available information, nine, or 36 percent, required hospital stays. Investigators said there were no deaths.
Fifteen of the 26 illnesses were in Maryland. Three were residents of the District of Columbia. Louisiana and Delaware each had two cases. And Colorado, New York, Pennsylvania and Virginia all had one illness each.
CDC first reported the outbreak on July 13, 2018.
In interviews, ill people answered questions about the foods they ate and other exposures in the week before they became sick. Of the 24 people interviewed, 22 (92 percent) reported eating crab meat in homes or restaurants.
State and local health officials collected information from restaurants and grocery stores where ill people reported buying fresh crab meat. FDA and regulatory officials in Maryland traced back the source of the crab meat from restaurants and grocery stores and identified multiple Venezuelan suppliers. The investigation did not determine a single firm as the only supplier of crab meat linked to the outbreak.
The CDC said the Maryland Department of Health (MDH) first warned Maryland residents on July 6 not to eat any fresh lump crab meat imported from Venezuela. MDH investigators collected unopened containers of crab meat from several stores where ill people reported buying lump crab meat. Multiple samples from several brands contained Vibrio parahaemolyticus. However, whole genome sequencing showed that isolates of Vibrio from the crab meat were not genetically related to the outbreak strain.
As a result of the outbreak investigation, the U.S. upped its testing of fresh crab meat from Venezuela. FDA testing did not find Vibrio parahaemolyticus in any samples tested but did find Salmonella and Listeria monocytogenes bacteria. The FDA prohibited sales of that contaminated crab meat in the United States.
CDC’s Advice to Consumers About Fresh Crab Meat:
Crab meat may contain Vibrio or other harmful germs. Follow these food safety tips to help prevent infection when using fresh, ready-to-eat crab meat:
- When buying raw crab meat – especially for use in cold dishes that do not need further cooking – look for the word “pasteurized” on the label.
- Fresh crab meat may be in refrigerated plastic containers. Pasteurization is the process of heating a product to a high enough temperature for a long enough time to kill illness-causing germs.
- When preparing a hot dish containing fresh crabmeat, such as crab cakes, crab dip, and crab casserole, use a food thermometer to make sure the dish reaches a safe minimum temperature of 165 degrees F.
- Reheat leftovers to the safe minimum temperature of 165 degrees F as measured by a food thermometer.
- Wash hands, utensils, and surfaces with hot, soapy water before and after handling or preparing dishes using fresh crab meat.
- Always follow the four steps to food safety – clean, separate, cook, and chill – to help prevent infection.
- If you think you became sick after eating contaminated crab meat, contact your health care provider.
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