CONTRA COSTA COUNTY (CBS SF) – Health officials in Contra Costa County on Wednesday warned residents of possible exposure to a confirmed measles case earlier this month.

Authorities said the patient visited John Muir Medical Center in Walnut Creek on August 11th between 11 a.m. and 2 pm. and the Chow restaurant location in Lafayette on August 14th between 9 a.m. and 11 a.m.

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Measles is a serious, highly contagious disease that is spread through the air when an infected person coughs or sneezes. It is not spread through food or drink.

“Most people have been vaccinated and therefore are protected and not at risk, even if they have shared the same indoor air-space with a contagious person,” said Contra Costa County Health Officer Dr. Chris Farnitano. “However, residents should be aware of the situation because anyone who was exposed and not protected by vaccine is at risk of developing measles.”

The person additionally visited popular indoor locations in Los Angeles County and Arizona during the infectious period. Arizona and Los Angeles County have also issued advisories to their residents regarding the possible exposure.

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Children routinely get measles vaccine at one year of age. People born before 1957 are considered immune as they likely had measles as children and developed immunity from the disease. Adults born after 1957 should review their vaccination records to ensure they have received the MMR vaccine or talk to their regular healthcare provider for questions about immunization status. Pregnant women and people who are HIV-positive or immune-suppressed are considered to be at high risk for measles if they are not vaccinated.

“We have notified people in Contra Costa who were known to be in close contact to the case, but not every potential contact at a public venue can be identified. Anyone who visited the following locations during the indicated dates and times could have potentially been exposed to the measles virus and should check immunity status.” said Paul Leung, Communicable Disease Programs Chief with Contra Costa Public Health.

Measles symptoms can begin one to three weeks after exposure and include high fever, runny nose, coughing and watery red eyes. A rash develops on the face and neck two to three days after the fever begins, and spreads down the body. The rash usually lasts five or six days. An infected person is contagious for several days before and after the rash appears.

Health officials urge anyone who shows symptoms of measles to contact their healthcare provider immediately.

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Information about measles is available online at the Contra Costa County Health Services website. Contra Costa County residents may also call 925-313-6740 for information.