The measles virus is highly contagious. If someone with measles coughs or sneezes, the virus in those droplets can survive for two hours afterward — infecting about 90% of the people lacking immunity who pass through that space.
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MMR — the modern combination vaccine against measles, mumps and rubella — provides stronger, longer-lasting protection against measles than the stand-alone measles vaccine typically given in the U.S. in the early 1960s.
The Washington state Senate passed a bill on Wednesday that would remove the personal belief exemption from the required vaccinations for measles, mumps and rubella. Here, people protest the related house bill outside Washington's Legislative Building in Olympia in February.
Dr. Eric Ball examines a healthy 5-day-old patient in his office in Ladera Ranch, Calif. Ball and colleagues decided this week to take only patients whose parents follow the recommended vaccine schedule.
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Public school student Julio Valenzuela, 11, grimaces as he gets a vaccination before the start of the school in Lynnwood, Calif., on Aug. 27. Vaccines are required for school attendance.
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Two boys study together at a Chicago yeshiva in 2009. Public health officials say this type of close physical contact caused a mumps outbreak to spread throughout several orthodox Jewish communities in and around New York City.
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