CDC map and tracker shows cases top last year

It’s not even the end of March yet, but measles cases in the United States have already surpassed the total number of measles cases in the country during all of 2023, according to new data released by the Centers for Disease Control and Prevention (CDC). Here’s what you need to know.

What is measles?

Measles is a virus that affects the respiratory system. It is highly contagious and can kill those infected with it, especially children. 

The CDC says that even in otherwise healthy children, measles will cause serious complications in one out of about every 1,000 cases. Those complications include permanent brain damage. Additionally, those who contract measles can suffer neurological conditions including the deterioration of behavioral and intellectual capabilities a full 7 to 10 years after they’ve had the virus.

Up to three of every 1,000 children who contract measles will die of the virus.

Where is measles spreading in 2024?

In the United States, there have already been 64 cases of measles reported this year. That may not sound like a lot, but it’s worrying because in all of 2023, there were only 58 reported cases of the disease. 

The CDC says the following states have reported cases of measles this year as of March 21, 2024: Arizona, California, Florida, Georgia, Illinois, Indiana, Louisiana, Maryland, Michigan, Minnesota, Missouri, New Jersey, New York City, Ohio, Pennsylvania, Virginia, and Washington.

Is there a vaccine for measles?

Yes, and there has been since 1963 when the first measles vaccine was licensed for public use. The CDC estimates that since the year 2000, the measles vaccine has prevented 57 million deaths worldwide. 

Measles was declared eliminated in the United States in 2000. However, since then cases have been steadily on the rise again.

Why is measles making a comeback?

It’s likely a combination of things. Blame the pandemic, vaccine hesitancy and fatigue, along with vaccine misinformation that spread across social media. As misinformation about COVID-19 vaccines spread due to both misunderstandings about vaccine technologies and ideological efforts to sway political opinions, vaccine hesitancy has started to rise in some pockets of populations. This was combined with lower routine children’s vaccination rates during the pandemic shutdowns, as ABC points out.

Unfortunately, that hesitancy isn’t just a problem for those who opt of getting themselves or their children vaccinated—it’s a problem for everyone since measles is an infectious disease. As PBS notes, 93% of kindergarteners in the United States have received their measles vaccination. However, that number is below the 95% threshold needed to prevent transmission in the public. 

Some states are doing better than others, however. In the 2022-23 school year, Mississippi had a measles vaccination rate of 98.4%. New York’s was 97.9% and Connecticut’s was 97.3%. However, there are states that are on the other end of the spectrum, too. Idaho had just an 81.3% vaccination rate during the same period. Alaska’s was 83.6% and Hawaii’s was 86.4%.

What happens now?

Given that 2024 measles cases in the U.S. have already surpassed the total number of 2023 cases—and we’re only in March—it’s likely that cases will continue to rise throughout the year. 

Those who are unvaccinated or who have children who are unvaccinated should talk to their doctor about getting the vaccine, which comes as part of an MMR jab, which protects against measles, mumps, and rubella. The CDC says two doses of the MMR vaccine is about 97% effective at preventing measles.