Family physician and public health specialist Dr. George Rust has warned some of his colleagues about a potential measles outbreak in Florida “for at least the past year,” he said, because of the rise in vaccine hesitancy in pockets of the community.
Now, his fears have come true.
The Florida Department of Health in Broward County is investigating six cases of measles as part of an outbreak at an elementary school in Weston. Two additional cases in children younger than 10 were reported by the Florida Department of Health, raising the county total to eight. Broward County Public Schools said the total within the district remains at six.
Statewide, “most kids in our public schools have had the vaccine, although there’s been some slippage in that in recent years. The kids who are not vaccinated, if they’re exposed to measles, 90% of them will get measles. So it’s a highly infectious disease, very contagious,” said Rust, a professor in the Florida State University College of Medicine and director of the university’s Center for Medicine and Public Health, who provides medical expertise to local public health departments.
On Tuesday, Florida Surgeon General Dr. Joseph Ladapo wrote in a letter to parents and guardians about the outbreak that it is “normally recommended” for people who have been exposed to measles and who are not vaccinated against the virus or who do not have a history of infection to stay home for up to 21 days, the length of the incubation period for measles. However, his letter leaves that up to choice.
The state health department is “deferring to parents or guardians to make decisions about school attendance,” Ladapo wrote.
The letter contradicts guidance from the US Centers for Disease Control and Prevention, which states that “unvaccinated children, including those who have a medical or other exemption to vaccination, must be excluded from school through 21 days after their most recent exposure.”
So, “there’s the possibility that children who are not immunized and who are susceptible to measles are attending school, potentially getting measles and then transmitting it to other kids,” Rust said. “Now, you’ve, on the one hand, allowed parents to make their own choices for the child who was not immunized, but you’ve also taken away some choices for those parents who may feel that their children should be protected.”
He added that “most public health experts” would agree that excluding unvaccinated children from the classroom during a measles outbreak protects that child from infection while reducing the risk of the virus spreading.
Measles is a highly contagious disease that can lead to complications and turn deadly, according to the CDC. Symptoms may include fever, cough, runny nose, watery eyes and a rash of red spots. In rare cases, it may lead to pneumonia, encephalitis or death. Measles also can weaken the immune system and may “delete” its immune memory.
“The CDC recommendations are telling us the right thing to do,” Rust said. “For the parents, keep your kid at home if they’re not immunized, and maybe go get them immunized.”
Experts recommend that children get the measles, mumps and rubella or MMR vaccine in two doses: the first between 12 months and 15 months of age, and a second between 4 and 6 years old. One dose is about 93% effective at preventing measles if you come into contact with the virus. Two doses are about 97% effective.
Nationwide, about 92% of US children have gotten the MMR vaccine by age 2, according to a 2023 report from the CDC – below the federal target of 95%.
“Local transmission of measles had been largely eliminated in the US, but we see sporadic outbreaks, especially when immunization levels drop even a little bit,” Rust said.
“If a susceptible person travels overseas and comes in contact with measles, they can bring it back into our communities and transmit it to others while they are still asymptomatic,” he said. “Measles is highly contagious – 90% of unvaccinated people who are exposed are likely to catch it – but vaccinated people are 97% protected.”
The measles virus can spread when an infected person coughs or sneezes, lingering in the air for up to two hours after they leave a room.
Cases have emerged in several states this year. As of Thursday, 35 measles cases have been reported by 15 jurisdictions: Arizona, California, Florida, Georgia, Indiana, Louisiana, Maryland, Minnesota, Missouri, New Jersey, New York City, Ohio, Pennsylvania, Virginia and Washington, according to the CDC. In comparison, a total of 58 cases were reported for all of last year.
“We have had scattered cases throughout the years in those who are unvaccinated. Recently, we know from the Louisiana Department of Health that two individuals, both of whom were unvaccinated and had traveled out of state, have been diagnosed with measles in the Greater New Orleans Area,” Dr. Katherine Baumgarten, the system medical director for infection control and prevention at Ochsner Health in New Orleans, wrote in an email Friday.
“Unfortunately, we’ve seen a decrease in the overall vaccination rate for measles as well as other diseases. This is very concerning and can most likely be attributed to children falling behind on the scheduled childhood vaccines through the recent pandemic and overall vaccine hesitancy in recent years,” she said. “With the decrease in vaccination rate, the highly contagious measles virus has reappeared and could spread through the general public among those unvaccinated.”
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In a statement Monday, the Association of State and Territorial Health Officials (ASTHO) said it is “alarmed” at the measles outbreaks in the United States.
“Measles was declared eliminated in the United States in 2000, but is still the most easily transmitted human virus presently in circulation. Thankfully, by following established public health principles, Americans can make informed decisions, prevent outbreaks, and protect our communities. Vaccination is the best and safest way to protect children,” Dr. Marcus Plescia, chief medical officer of ASTHO, said in the statement.
“Because of the risk of severe disease from measles and the high likelihood of transmission to others even before symptoms are evident, well-established public health practice recommends that unvaccinated persons exposed to measles stay home for at least 21 days to prevent further growth of the outbreak,” he said. “While this is undoubtedly disruptive to the persons impacted, imagine how much more disruptive it would be if measles takes hold again in the United States, spreading widely, and impacting children and communities across the entire nation.”
CNN’s Carlos Suarez contributed to this report.