Orange County Convention Center, photo via OCFL Twitter.

Orange County and four other Florida counties have been identified as at high risk for a measles outbreak, according to a study published by The Lancet Infectious Diseases.

The study which analyzed global air travel, non-medical exemption rates, and county population sizes, identified 25 counties across the country at highest risk for a measles outbreak.


Cook County, Illinois ranked highest for risk of an outbreak followed by Los Angeles, Ca. Several Florida Counties also ranked within the study’s top 25:  Miami-Dade at No. 3, Broward at No. 7, Orange County at No.14, and Hillsborough at No.17.

According to the study, the number of measles cases in 2019 is the highest since measles was declared eliminated from the US in 2000. Of the more than 760 cases reported in 2019, two were in Florida, the Orlando Sentinel reports.

According to the Sentinel, Florida maintains above a 90 percent vaccination rate, but certain areas within the state have exemption rates as high as 30% which concerns health professionals.

The study cites two factors contributing to the dramatic spike in measles cases inside the U.S.: international travel from countries experiencing outbreaks and low vaccination rates fueled by non-medical exemptions.

The researchers at the University of Texas at Austin and Johns Hopkins University were also able to specify a collection of countries which contribute most to the spread of measles within the U.S. Among the top are India, China, Mexico, Japan, Ukraine, Philippines, and Thailand.

Measles is a highly contagious illness transmitted by the respiratory route, The Lancet reports. Prior to the introduction and widespread use of the measles vaccine, the illness claimed more than 2 million deaths annually. Today that number is approximately 100,000 a year, according to the CDC.

The majority of measles cases this year affect the unvaccinated, the CDC reports.

More information and locations where vaccinations are available can be located here.