Measles outbreak spreads to 7 Ohio daycares, 1 school, all with unvaccinated children

A false color image of the measles virus. Arizona Department of Health

A measles outbreak in Ohio quickly spread, spreading to seven daycare centers and a school, all with unvaccinated children, according to local health officials. The outbreak highlights the risk of this highly contagious but vaccine-preventable disease proliferating amid declining vaccination rates.

On Nov. 9, the City of Columbus and Franklin County, which includes Columbus, health departments announced an outbreak at a daycare center that had sickened four unvaccinated children. Officials expected more cases to follow.

As of Wednesday morning, there were 18 confirmed cases at seven daycares and one school. All cases are in unvaccinated children and at least 15 cases are in children under 4 years old. At least six required hospitalization, Ars Kelli Newman, a spokesperson for Columbus Public Health, told Ars.

Health officials are now working to curb the outbreak, including conducting contact tracing in affected facilities, coordinating measles awareness efforts with local health care providers, and contacting families to inform them and encourage vaccination against measles-mumps-rubella vaccine (MMR).

"MMR vaccines are very safe and very effective in preventing measles," Newman told Ars in an email. "We offer walk-in MMR vaccines at Columbus Public Health Monday through Friday each week. We haven't yet seen an uptick here on MMR vaccines from what we usually do, but that's not indicative of global adoption as we don't know what is being donated by community providers."

Ars contacted the Ohio Department of Health, which maintains statewide records of vaccination rates, but figures for the city of Columbus and Franklin County were not readily available. We will update this story if provided.

Risky situation

Statewide, however, vaccination rates have plummeted amid the pandemic as well as dangerous anti-vaccine misinformation. In the 2019-20 school year, 92.4% of kindergarteners in Ohio received the MMR vaccine. But in the 2020-2021 school year, coverage fell to 89.6%. Public health experts from the Centers for Disease Control and Prevention say a rate of 95% is ideal for preventing the spread. Additionally, statewide numbers may mask pockets of extremely low vaccination rates, where vaccine-preventable diseases can easily spread.

Measles, a virus that is spread by coughing, talking or simply being in the same room with someone, will infect around 90% of unvaccinated people who are exposed. Once infected, symptoms usually appear seven to 14 days later, beginning with a high fever that can exceed 104°F, cough, runny nose, and watery eyes. A few days later, a telltale rash develops.

In the decade before a measles vaccine became available, the CDC estimates that the virus infected 3-4 million people in the United States each year, killing 400-500, hospitalizing 48,000 and causing encephalitis (swelling of the brain) in 1,000 people. .

Measles was declared eliminated from the United States in 2000, which means that, thanks to vaccination, it is no longer spreading continuously in the country. But it has not been eradicated worldwide and therefore is still brought into the country from time to time by travelers, which poses a constant threat of epidemics in all areas with low vaccination rates. If measles is introduced and continues to spread for more than 12 months, the United States will lose its measles elimination status, which it nearly lost in 2019.

Editor's Note: This post has been updated to correct a typo. Measles was declared eliminated in the United States in 2000, not 2020.