Vibrio parahaemolyticus Infections Linked to Fresh Crab Meat Imported from Venezuela (Final Update)

Posted September 27, 2018 at 3:15 PM ET

This outbreak investigation is over. However, Vibrio is an important cause of illness in the United States. For information on steps people can take to reduce their risk of Vibrio infection from crab meat, read the Advice to Consumers, Restaurants, and Retailers.

Highlights
Outbreak Summary

Introduction

CDC, state and local health officials, and the U.S. Food and Drug Administration (FDA)external icon investigated a multistate outbreak of Vibrio parahaemolyticus infections linked to eating fresh crab meat imported from Venezuela. This crab meat was labeled as “fresh” or “pre-cooked” and was a ready-to-eat product.

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. DNA fingerprinting is performed 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.

Illnesses began from April 1 to July 19, 2018. Ill people ranged in age from 26 to 78 years, with a median age of 55. Among ill people, 54% are male. Among people with available information, 9 (36%) were hospitalized. No deaths were reported.

Investigation of the Outbreak

Epidemiologic, laboratory, and traceback evidence indicated that crab meat labeled as fresh or precooked and imported from Venezuela was making people sick.

In interviews, ill people answered questions about the foods they ate and other exposures in the week before they became ill. Of the 24 people interviewed, 22 (92%) 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 identify a single firm as the only supplier of crab meat linked to the outbreak.

The Maryland Department of Health (MDH) warned Maryland residentsexternal icon on July 6, 2018, 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, FDA increased 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. That contaminated crab meat was not allowed to be sold in the United States.

This outbreak investigation is over.

Previous Outbreak Announcements

Introduction

CDC, state and local health officials, and the U.S. Food and Drug Administration (FDA)external icon are investigating a multistate outbreak of Vibrio parahaemolyticus infections linked to eating fresh crab meat imported from Venezuela.

Public health investigators are using the PulseNet system to help identify illnesses that may be part of this outbreak. PulseNet is the national subtyping network of public health and food regulatory agency laboratories coordinated by CDC. DNA fingerprinting is performed 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.

As of July 12, 2018, 12 people infected with Vibrio parahaemolyticus who ate fresh crab meat have been reported from 3 states and the District of Columbia. A list of the states and the number of cases in each can be found on the Case Count Map page. WGS showed that available isolates from people in this outbreak are closely related genetically. This close genetic relationship means that people in this outbreak are likely to share a common source of infection.

Additional ill people associated with this outbreak include people who reported eating crab meat and who had a diagnostic test showing they were infected with Vibrio, which may or may not be the species Vibrio parahaemolyticus.

Illnesses started on dates ranging from April 1, 2018 to July 3, 2018. Ill people range from 26 to 69 years, with a median age of 54. Among ill people, 67% are female. Four people (33%) have been hospitalized. No deaths have been reported.

This outbreak can be illustrated with a chart showing the number of people who became ill each day. This chart is called an epidemic curve or epi curve. Some illnesses might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported. This takes an average of 2 to 4 weeks. For a more detailed explanation, see the Timeline for Reporting Cases of Salmonella Infection, which is similar for reporting of Vibrio cases.

Investigation of the Outbreak

Epidemiologic evidence indicates that crab meat labeled as fresh or precooked imported from Venezuela is a likely source of this outbreak. Investigation into the source is ongoing.

Public health officials in Marylandexternal icon first detected this outbreak when they identified Vibrio infections among people who ate crab meat.

FDA and regulatory officials in Maryland traced back the source of the crab meat from the restaurants and grocery stores where ill people bought crab meat. Preliminary evidence gathered in this investigation showed that the crab meat was imported from Venezuela.

Based on the information available at this time, CDC recommends that consumers not eat, restaurants not serve, and retailers not sell precooked fresh crab meat imported from Venezuela until further notice. This type of product may be labeled as fresh or precooked. It is commonly found in plastic containers. Food contaminated with Vibrio usually looks, smells, and tastes normal.

This investigation is ongoing. FDA and state regulatory officials are working to determine the distribution of imported crab meat and if it was sold in other states. CDC will provide updates when more information is available.

At A Glance
  • Case Count: 26
  • Jurisdictions: 8
  • Hospitalizations: 9
  • Deaths: 0
  • Recall: No
Photo of crab meat.