A hepatitis A outbreak was declared in Los Angeles County on Tuesday, according to the Los Angeles Times, just days after San Diego health officials announced an outbreak of the contagious disease in that city. While only 10 people have been confirmed infected in Los Angeles County, the San Diego outbreak is currently much larger: More than 400 people have been sickened there, and at least 16 have died.
Most of those infected in San Diego have been homeless, according to a statement from the county, and health officials say the virus has spread through contact with a “fecally contaminated environment.” In Los Angeles County, officials said they’d documented five people with the illness who had recently traveled to San Diego or Santa Cruz (where cases related to the San Diego outbreak also appeared) . But two of the newly infected people in Los Angeles County were homeless and seem to have been infected locally, which triggered the outbreak declaration.
To curb transmission rates, San Diego officials have hosted more than 250 mass vaccination events, installed hand-washing stations throughout the city, and made efforts to sanitize areas where homeless people live and congregate, spraying down sidewalks and streets with diluted bleach, reports NPR. Los Angeles health workers have also adopted similar practices.
Hepatitis A is highly contagious, says David Mulligan, MD, chief of transplantation and immunology at Yale-New Haven Health Transplantation Center, and it’s often misunderstood. (Dr. Mulligan has not been involved with the California outbreaks, but he does treat hepatitis patients at Yale.) Here are four things to know about this headline-making disease.
Hepatitis A is transmitted orally
Unlike hepatitis B and C—which are transmitted through sex or exposure to infected blood—hepatitis A is usually spread through ingestion of contaminated food. “One of the most common causes is shellfish and raw seafood, like oysters and clams,” says Dr. Mulligan. “If these foods are contaminated with the virus, eating them can make you pretty sick.”
Other foods can become contaminated with the virus too, especially if they’re in contact with fecal matter from an infected person. In the San Diego outbreak, health officials seem to think the virus has spread because of sanitation issues and lack of public-bathroom access.
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