That's more than the 667 cases reported in 2014, when one large outbreak primarily among unvaccinated people in Amish communities in OH accounted for more than half the total that year.
"The very best way to prevent the measles or any vaccine preventable diseases is to get the vaccine", said Hamilton. Symptoms include fever, runny nose, cough and rash.
Measles' return may be an early warning sign of resurgences in other vaccine-preventable diseases such as rubella, chickenpox and bacterial meningitis, Schaffner said.
"Ever since there was vaccination, there were people who were against vaccines", Moss says. Most of those cases have been in unvaccinated people in Orthodox Jewish communities. "The only way to protect against measles is to get vaccinated".
"Measles virus can live in the air and on surfaces for two to three hours", Nydam said. Among those who are unvaccinated, it may be because of personal beliefs and medical reasons. People born between 1957 and 1989 generally had only one MMR dose.
Of those 626 cases, 487 were in people 19 and younger. In addition to New York City, there are measles outbreaks in California; Rockland County, New York; New Jersey; and MI, where nearly all 43 cases are linked to one man who traveled to the Detroit area from Brooklyn, unaware that he had measles.
The CDC will again update its measles figures Monday. However, there are other states experiencing outbreaks such as NY and California. The public information officer of the Michigan Department of Health and Human Services, Lynn Sutfin, said that a male from NY had traveled to the Southeast Michigan using a vehicle.
Hamilton says one case has been identified in Florida so far and no reported measles cases in Leon or surrounding counties.
A case in point is the 43-year-old Israeli flight attendant for El Al who remains in a coma after catching the measles and developing encephalitis, Offit said.
The FDA published a statement this week that emphasizes the measles vaccine's safety.
"Part of the problem is that people are no longer fearful of these diseases, and their fears have shifted to vaccines", Salmon says. The virus has been recorded in 22 states so far in 2019, the CDC said. But when measles lands in a community where rates of vaccination are low, that's when it takes off, she added. There were 963 cases reported in the United States in 1994 and 508 in 1996. The previous record was 694 in 2014.
Similar efforts have eradicated several once-common diseases throughout the entire Caribbean - including endemic smallpox in 1971, polio in 1994, and rubella and congenital rubella syndrome in 2015, according to the Caribbean Public Health Agency.
Still, some people won't vaccinate their children because they erroneously believe the vaccine isn't safe and may cause autism. Two doses are about 97% effective.
With any medicine, including vaccines, there is a chance of reactions, according to the CDC.