Health officials in Southern California have issued a warning to avoid eating raw oysters imported from certain areas of Mexico after more than 200 people got sick from suspected norovirus infection.

Norovirus is a highly contagious gastrointestinal illness that causes vomiting and diarrhea. The virus-causing infection typically spreads through direct contact with an infected person or consumption of contaminated food or drink.

"The Los Angeles County Department of Public Health is reporting that there are more than 150 suspected local cases of gastrointestinal illness linked to the consumption of raw oysters, likely caused by norovirus," the County of Los Angeles Public Health said in a news release.

"At this time, Public Health is warning consumers not to eat raw oysters from Laguna De Guerrero Negro, Baja California, Mexico; Laguna Manuela, Baja California, Mexico and Bahia Salina, Sonora, Mexico because they may be linked to outbreaks of norovirus illnesses in California. Before eating raw oysters, consumers should ask the vendor/restaurant where the oysters were harvested," the officials cautioned.

Meanwhile, health officials in San Diego County reported 69 confirmed and probable cases of norovirus infection. However, officials said the cases were mild, and no hospitalizations were reported in the county.

"Norovirus is typically a mild illness but can cause dehydration, especially for the very young and very old. Given the increasing number of cases, the chance for others at greater risk for more severe illness in the same home is also increased. I want to remind people who become ill, and those that live with them, to wash their hands frequently to avoid contaminating surfaces and foods that could further spread the infection," Dr. Ankita Kadakia, deputy county public health officer said.

The U.S. Food and Drug Administration issued two separate warnings advising restaurants and food retailers not to serve or sell oysters imported from Bahia Salina in Sonora, as well as Laguna Manuela and Laguna De Guerrero Negro in Baja California, Mexico, as they may be potentially contaminated with norovirus.

Food contaminated with norovirus may look, smell and taste normal. However, eating them can cause severe illness in some, particularly immunocompromised individuals.

So, officials have requested retailers and restaurants to dispose of the contaminated products by throwing them in the garbage or initiating return or destruction with their distributors.

Signs of Norovirus Infection

While the most common norovirus symptoms include diarrhea, vomiting, nausea and stomach pain, some people may also experience fever, headache and body aches. The symptoms typically begin 12 to 48 hours after exposure to the virus. Most people with mild infection may recover within three days. However, young children, the elderly and people with other medical conditions may require medical attention if the vomiting and diarrhea become severe and result in dehydration.