Louisiana Oyster Warning Issued After Norovirus OutbreakDec 31, 2007 | Parker Waichman LLP Some Louisiana oysters could cause norovirus. The Food and Drug Administration (FDA) is warning consumers against eating oysters harvested from a part of West Karako Bay in Louisiana for possible contamination of the norovirus, also called Norwalk. The FDA said customers must avoid mussels harvested between December 3rd and December 21st from Growing Area Three of the bay. At least seven victims have been reported after eating oysters at a Tennessee restaurant; the mussels were harvested from West Karako Bay and shipped by Prestige Oyster Company of Theriot, Louisiana.
Noroviruses are a group of related viruses that cause acute gastroenteritis in humans; recent studies confirm that norovirus causes around half of all gastroenteritis worldwide. Norovirus infection causes nausea, vomiting, diarrhea, and stomach cramping. Other symptoms include chills, headache, low-grade fever, muscle aches, and a general sense of tiredness. The illness often begins suddenly and the infected person may feel very sick. In most cases, the illness is self-limiting with symptoms lasting for a couple of days. Children tend to vomit more than adults and very young children, the elderly, and those with weakened immune systems are more vulnerable. Symptoms usually occur within 12 to 48 hours from exposure. People may feel very sick and vomit many times a day, but most people get better within a couple of days and suffer no long-term health effects; however, some are unable to drink enough liquids to replace what they lost and can become dehydrated and require medical attention.
The FDA said cooking destroys the virus—eliminating the risk of illness—and recommended consumers cook the mussels thoroughly instead of eating them raw. They also advised consumers to discard oysters harvested from the identified area and within the specified period.
Noroviruses are found in the stool or vomit of infected people and people can become infected with the virus by eating food or drinking liquids contaminated with norovirus; touching contaminated surfaces or objects and placing their hand in their mouth; having direct contact with an infected person and showing symptoms (for example, when caring for someone with illness or sharing foods or eating utensils with someone who is ill). Persons working in day-care centers or nursing homes should pay special attention to children or residents who have norovirus illness. Noroviruses are very contagious and can spread easily from person to person. People are contagious from the moment they begin feeling ill to at least three days after recovery and some may be contagious for as long as two weeks after recovery.
There are many different strains of norovirus, making it difficult for a person’s body to develop long-lasting immunity; therefore, norovirus illness can recur throughout a person’s lifetime. Also, because of differences in genetic factors, some people are more likely to become infected and develop more severe illness than others. There is no antiviral medication that works against norovirus and there is no vaccine to prevent infection; norovirus infection cannot be treated with antibiotics, as this is a virus and not a bacteria and antibiotics work to fight bacteria, not viruses.