An unvaccinated child in Connecticut has been diagnosed with measles, public health officials confirmed, the state’s first confirmed case of the highly contagious disease since 2021.

The child, who is under the age of 10, lives in Fairfield County, the Connecticut Department of Public Health announced last week. The child had recently travelled internationally before showing symptoms including cough, runny nose, congestion, fever, and eventually a full-body rash.

“The single best way to protect your children and yourself from measles is to be vaccinated,” Connecticut DPH Commissioner Manisha Juthani, MD, said in a statement. “One dose of measles vaccine is about 93 percent effective, while two doses are about 97 percent effective.”

The United States has seen a record high 1,912 measles cases since the disease was declared eliminated in 2000, the CDC reported. As of July 7, this year has also reported the most cases in more than 30 years, according to the International Vaccine Access Center.

Earlier this year, West Texas saw a measles outbreak of hundreds of cases, mostly among unvaccinated children who had to be hospitalized. About one in five unvaccinated people diagnosed with measles are hospitalized, Connecticut DPH said, and the disease can be especially dangerous for children.

“We must ensure we continue to protect those who matter most – children and other vulnerable people – from vaccine preventable illnesses through on-time vaccination,” Juthani said.

Health Secretary Robert F. Kennedy Jr., known for his overhaul on the childhood vaccine schedule and doubts on COVID vaccine safety, endorsed the measles vaccine after two children died from measles amid the outbreak in Texas.

“The most effective way to prevent the spread of measles is the MMR vaccine,” Kennedy said in April. 

Earlier this year, a Vermont child who had recently traveled internationally was confirmed to have been infected with measles. In March, a man tested positive for measles after traveling on an Amtrak train originating from Boston’s South Station to Washington D.C.

Molly Farrar is a general assignment reporter for Boston.com, focusing on education, politics, crime, and more.