The measles outbreak in the United States continues to grow, with the number of cases this year now reaching 1,044 as of Friday, according to the US Centers for Disease Control and Prevention.
Those cases have been confirmed in 28 states.
The states that have reported cases to CDC are Arizona, California, Colorado, Connecticut, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kentucky, Maine, Maryland, Massachusetts, Michigan, Missouri, New Mexico, Nevada, New Hampshire, New Jersey, New York, Oklahoma, Oregon, Pennsylvania, Texas, Tennessee, Virginia, and Washington.
The number of cases this year marks the greatest number reported in the United States since 1992 and since measles was declared eliminated in 2000, meaning it was no longer continuously transmitted in the country.
Earlier this month, the number of measles cases surpassed 1,000 in the United States.
At the time, US Health and Human Services Secretary Alex Azar said in a statement that “the Department of Health and Human Services has been deeply engaged in promoting the safety and effectiveness of vaccines, amid concerning signs that there are pockets of undervaccination around the country. The 1,000th case of a preventable disease like measles is a troubling reminder of how important that work is to the public health of the nation.”
Ongoing measles outbreaks in various states are linked to travelers who brought the measles virus back from traveling to other countries such as Israel, Ukraine and the Philippines, where large measles outbreaks are occurring, according to the CDC.
In a given year, the number of measles cases can continue to climb due to an increase in the number of travelers who come in contact with the measles virus abroad and then bring it back to the United States. Measles can further spread in communities with pockets of unvaccinated people, the CDC noted.
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Measles is one of the most highly contagious diseases in existence, spreading through coughing and sneezing, and can linger in the air for up to two hours. If someone who is not immune to the virus breathes the air or touches an infected surface, they can become infected, according to the CDC.
To protect yourself, doctors recommend immediate vaccination. Other steps: wash hands often or use hand sanitizer, avoid touching your eyes and mouth, disinfect surfaces and toys with standard household products, and refrain from coming into close contact or sharing silverware with anyone who’s sick.
CNN’s Debra Goldschmidt contributed to this report.