Nearly a dozen cases of measles have been reported in Pennsylvania, Virginia, and Georgia in recent weeks, according to local health departments. International travel, along with declining global vaccination rates, are likely behind this wave of new cases, experts say.
The Philadelphia Department of Public Health confirmed at least nine cases of measles in the last month after one person contracted the highly contagious virus outside the United States and exposed a father and son. This exposure then led to an outbreak in daycares in Philadelphia.
A single case of measles was confirmed in “an unvaccinated resident of the Atlanta metropolitan area,” the Georgia Department of Public Health announced on Thursday. “The individual was exposed to measles while traveling abroad,” it said in a press release.
It’s not just the United States that is seeing a once-eliminated disease resurge. In the United Kingdom, the measles outbreak continues to rise: there have been 216 confirmed cases and 103 probable cases reported since October.
Why is measles spreading?
Measles was eliminated in the United States in 2000, after zero spread of the virus for over a year, largely due to a “highly effective vaccination campaign,” according to the U.S. Centers for Disease Control and Prevention.
However, the virus has not been eliminated globally. There are several countries with active outbreaks.
If an unvaccinated person travels to a country where the disease is still common, becomes infected, and brings it back to the U.S., they can spread the virus to other unvaccinated individuals within the U.S.
Decline in vaccination rates
Vaccination rates in the U.S. remain low, especially among children, according to Dr. Christina Johns, spokesperson for the American Academy of Pediatrics.
About 92% of children in the U.S. have been vaccinated against measles, mumps, and rubella (the MMR vaccine) by age 2, according to a 2023 CDC report – below the federal target of 95%.
The percentage of kindergarten students who received the state-required measles vaccines also remained below the federal target for the 2022-23 school year, according to CDC data. And the rate of vaccine exemptions for children reached the highest level ever recorded in the U.S.
Children should receive two doses of the MMR vaccine, according to the CDC: the first dose at 12 to 15 months of age and the second at 4 to 6 years of age.
Before the national measles vaccination program, about 3 million to 4 million people contracted the virus every year, and about 400 to 500 died.
The last significant measles outbreak in the U.S. occurred in 2018-19 in Rockland County, New York, concentrated among unvaccinated children in Orthodox Jewish communities.
Although the CDC reported only 56 cases of measles in 2023, Dr. Johns says that’s a lot when there is a highly effective vaccine available.
Spread and symptoms of measles
The measles virus can spread when an infected person coughs or sneezes, remaining in the air for up to two hours afterward. The virus can also live on surfaces like doorknobs for approximately the same period.
When symptoms begin, they are similar to those of many respiratory illnesses – high fever, cough, red eyes, runny nose, and congestion – followed by a rash.
The incubation period for measles is very long. It takes about 10 to 12 days for initial symptoms to appear after exposure.
Because of this, most infected people assume their respiratory symptoms are nothing more than a cold and end up spreading it to many others. This gives the virus a high capacity to spread.
Health risks
Measles can cause serious complications, especially in children under 2 years old, such as blindness, encephalitis or inflammation of the brain, and severe pneumonia.
What to do if you have been exposed to measles?
If you are fully vaccinated against measles, your chance of infection after exposure is very low because the two childhood doses typically provide lifelong immunity, experts say.
But for those who are unvaccinated or have weakened immune systems, the risk increases. They should let the virus simply run its course. There is no specific antiviral treatment, and medical care is mainly supportive: stay home, do not go to school or work, rest, and drink plenty of fluids.
But if a person infected with measles shows symptoms of encephalitis, such as headache, high fever, or seizures, they should be taken to the hospital immediately.
Source: CNN