Symptoms include a high fever, cough, runny nose and red, watery eyes, followed by a blotchy rash.
Measles is still common in many parts of the world including some countries in Europe, Asia, the Pacific, and Africa.
Those who are not vaccinated but are exposed to measles should avoid public places, like school and work, for up to 21 days. That's up substantially from the 118 cases reported in 15 states and the District of Columbia in all of 2017. Measles elimination is defined as the absence of continuous transmission for 12 months or more in a specific geographic area.
The other states reporting cases of the measles were Arkansas, California, Connecticut, Florida, Illinois, Indiana, Louisiana, Maryland, Michigan, Missouri, Nevada, New Jersey, New York, North Carolina, Oklahoma, Oregon, Pennsylvania, Tennessee and Washington.
From Jan. 1 to July 14, 107 people had contracted the disease, federal Centers for Disease Control officials said Wednesday. Without treatment, symptoms typically disappear within two or three weeks, but one or two out of every 1,000 children will die from complications. It is likely that the number of cases in 2018 will be much more than that.
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However, LDH is disputing the reports of an "outbreak", posting on their official Facebook page that it stems from a "misinterpretation of the language on the CDC's Measles Cases and Outbreaks website". Herd immunity is achieved when at least 95 percent of the total population of a country gets the recommended two doses of the vaccine.
The cases in Florida's Gulf coast county of Pinellas are the first there in 10 years.
This is the fifth case reported in Florida and there are no locally-acquired cases in Jacksonville.
More spreading of measles also occurs in communities with pockets of unvaccinated people, according to the CDC.
Unvaccinated infants are especially vulnerable to complications of measles, so the CDC advises they are best protected by herd immunity.