Measles has spread to 28 states and infected more than 1,022 people since the start of 2019, according to the Centers for Disease Control and Prevention (CDC). The number of cases rose by 41 in the last week alone, and they're centered in several localized zones. The largest number of cases have occurred in New Jersey and New York; in fact, minors without the MMR vaccine were banned from public places in Rockland County, New York, for about two weeks this spring. Washington had also declared a state of emergency over the outbreak.
So far, 2019 has experienced the largest measles outbreak since 1992. And the CDC worries that summer camps and travel plans will further spread measles – which is why everyone should check their vaccination status before traveling.
A highly contagious virus, measles was technically eliminated in America 20 years ago, but the recent uptick has two major causes: international travelers bringing measles into the U.S., and unvaccinated children coming into contact with it. For example, the virus has been hitting New York City's Orthodox Jewish communities, where travelers returning from countries like Israel have infected unvaccinated community members. Since news reports only tell part of the story, here's what concerned parents need to know about the measles outbreak.
Infectious measles droplets survive up to two hours after the infected person has left an area. And since the contagious period is long—from four days before a rash appears until four days after—a single infected person can come in contact with hundreds of people.
Measles can lead to pneumonia or ear infections. Most kids recover easily, but in approximately every 1,000 cases, one person will suffer encephalitis (brain inflammation) that causes permanent brain damage. Two to three people per 1,000 cases will die.
A study the February 2015 issue of the journal Pediatrics showed that the measles vaccine is safe. This goes for both forms of the vaccine available in the U.S.: measles-mumps-rubella (MMR) and measles-mumps-rubella-varicella (MMRV). Researchers tracked more than 600,000 1-year-olds over 12 years to confirm the vaccine's safety.
The measles vaccine requires one dose at age 12-15 months, and another dose at age 4-6 years, according to the CDC. But given the recent measles outbreak, the New York State Department of Health recommends a vaccination at six months in affected areas. Ninety-five percent of kids will develop immunity when they get their first vaccination. The second dose before kindergarten gives 99 percent immunity. By contrast, 90 percent of exposed, unvaccinated people will get sick with measles. Immunity can disappear over time and 5 in 100 will lose their immunity by their late teens or adulthood.
If your child is exposed and unvaccinated, or hasn't gotten a booster shot, the vaccine protects when given within 72 hours of exposure.
Because of increased risk, the AAP and CDC now recommend vaccinating 6- to 12-month-olds if they’re traveling internationally. However, the regular two-shot series after 12 months is still necessary to ensure long-lasting immunity. If an adult isn’t vaccinated, the CDC says they should get two doses of the vaccine before traveling, as long as the doses are separated by a minimum of 28 days. Learn more about the measles vaccine for travelers here.