Measles cases spiked last week as New York City's ongoing outbreak worsened, the Centers for Disease Control and Prevention said Monday.
In just one week, the number of measles cases around the country so far this year jumped 20 percent, according to new CDC data. The total now stands 465, the second-highest since the the disease was declared eradicated from the U.S. in 2000.
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Of the 78 new cases reported last week, 60 were in New York city, the agency said. Officials in the area are battling an outbreak that started in the fall and continues to spread, especially among Orthodox Jewish communities where people are less likely to be vaccinated.
In Brooklyn's Williamsburg community alone, 41 new cases were reported in the past week, according to the city's health department. Since October, there have been 259 confirmed cases in Brooklyn and Queens, the health department said, most of which involved the Orthodox Jewish community.
In New York's Rockland County, another nine cases were reported, the CDC said, bringing the total number of cases in the area to 167 since the fall. County officials took the extraordinary step of banning unvaccinated children from public places, though a judge struck the measure down late last week.
The CDC linked the outbreaks in New York, Rockland County and New Jersey to people bringing the disease back from Israel, where a large outbreak is occurring.
Measles is highly contagious, infecting up to 90 percent of unvaccinated people who are exposed to it, according to the Centers for Disease Control and Prevention. The virus can live in the air for up to two hours after an infected person coughs or sneezes, according to the CDC, meaning people can be exposed to it without ever knowing. People can be infected for days before showing signs of the virus, such as a fever, runny nose or a rash.
Since January, the disease has been reported in 19 states. Outbreaks, defined as three or more cases, are ongoing in five areas: New York City, New York State's Rockland County, Washington, New Jersey, California's Santa Cruz County, California's Butte County and Michigan.