Bay Area health departments issued a joint statement Friday, warning people measles is on the rise nationally and to be up to date on their vaccinations.
The Association of Bay Area Health Officials (ABAHO) said "The best protection against measles is two doses of the measles-mumps-rubella (MMR) vaccine, which protects you for life. This is particularly important for anyone travelling internationally in the upcoming months."
The group said the Centers for Disease Control and Prevention (CDC) reports in 2024 there have been 64 confirmed cases of measles across 17 jurisdictions, with more than 90 percent of those cases linked to international travel, as measles is circulating in many regions in the world, including popular tourist and business destinations.
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Most cases in the U.S. have been among children aged 12 months and older who had not received the MMR vaccine.
"With three major airports, the Bay Area is a hub for international travel, increasing the potential for exposure to this highly contagious virus," ABAH said, in a statement. "For individuals or families that plan to travel internationally, anyone who is not vaccinated against measles is at increased risk of getting infected.
"Plan early before international travel and check your destination and the CDC's Global Measles Travel Health Notice for more travel health advice, including where measles outbreaks have been reported. Parents should consult with their child's health care provider prior to travel."
Officials said, after returning to the U.S., watch for signs and symptoms of measles for three weeks.
"While MMR vaccination rates have been high in the Bay Area, it's important to confirm vaccination history," the group said. "Having documentation of your vaccination status can help you avoid being quarantined if you are exposed. The CDC offers accelerated vaccination guidelines for persons, including children under 12 months, who plan to travel internationally."
ABAHO said measles symptoms include fever, cough, runny nose, and conjunctivitis (pink eye), followed 2-4 days later by a rash. The virus is transmitted through direct contact with infectious droplets or through the air when an infected person breathes, coughs, or sneezes. Infectious droplets can linger in indoor air for several hours.
About one in five people infected with measles requires hospitalization, and nearly 1 to 3 of every 1,000 children who become infected with measles will die from respiratory and neurologic complications, according to the CDC.
ABAHO said measles presents the greatest risk to children under 5 years of age, adults over 20 years of age, pregnant women, and people with compromised immune systems.
Vaccination is highly effective at preventing measles. The MMR vaccine is recommended for children aged 12-15 months, with a second dose administered between ages 4 and 6 years old.
Infants (6-12 months) can start vaccination early prior to international travel.
Teenagers and adults with no evidence of immunity should be vaccinated right away.
For questions about the MMR vaccine and immunization records, check with your health care provider and access your digital vaccine record.
ABAHO is made up of health Officers from the counties of Alameda, Contra Costa, Marin, Monterey, Napa, Santa Clara, Santa Cruz, San Benito, San Francisco, San Mateo, Solano, Sonoma, and the city of Berkeley.
