Fewer kids in the United States got vaccinated against measles and other viruses last year, based on the latest figures.

The U.S. Centers for Disease Control and Prevention (CDC) reported this week that the national coverage with state-required vaccines among kindergarten students dropped to 93% for the 2021-2022 school year. Two years ago, the rate was at 95%.

During the 2020-2021 school year, the national coverage declined from 95% to 94%. The latest data showed that the percentage of schoolchildren immunized against measles and other viruses fell for the second straight year.

According to the public health agency, the exemption rate remained low at 2.6% in the previous year. Meanwhile, around 3.9% were not up to date with their measles, mumps and rubella vaccine in the same period.

The CDC pointed out that COVID-19-related disruptions continued to prevent the return to prepandemic coverage despite the widespread implementation of in-person learning across the country.

“We know measles, mumps, and rubella vaccination coverage for kindergartners is the lowest it has been in over a decade … and that is something to be concerned about,” the CDC’s director of immunization services Georgina Peacock said in a briefing, as quoted by WebMD.

In 2021, a record high of nearly 40 million children missed their measles vaccination, according to a joint report by the CDC and the World Health Organization (WHO) released last year. Of the figure, 25 million missed their first dose, while an additional 14.7 million missed their second dose.

In the wake of the report, experts feared that measles would become a big threat in many places in the coming months. At the time, they also blamed the COVID-19 pandemic for the weakened measles surveillance and delays in immunization programs and activities.

The latest figures released by the CDC also showed that kindergarten immunization rates for other conditions, including diphtheria, tetanus, pertussis, polio and chickenpox, also dipped, according to WebMD.

The CDC urged public health practitioners to increase their follow-up efforts with undervaccinated students to reduce the impact of vaccination disruptions amid the ongoing pandemic.

The agency’s update came days after the measles outbreak in Ohio, which initially started in June 2022, reportedly subsided. But authorities said it’s too soon to tell if the outbreak has ended.

“The end of an outbreak isn’t declared until 42 days after the last infected person develops a rash,” Columbus’s Health Commissioner Dr. Mysheika W. Roberts said.