Kansas health officials have confirmed 23 measles cases, marking an outbreak for the state as infections in at least 17 states have led to the most cases in the U.S. in a single year since 2019.
The Kansas outbreak is spread across 6 southwest counties, the state’s Department of Health and Environment said Wednesday.
The majority of cases, 20, are individuals who were not vaccinated against the infection. Fifteen cases are in school-aged children, between ages 5 and 17, six patients are 4 years old or younger and two are over 18, officials said.
Health officials in Ohio have also reported 10 cases this week.
“Given the measles activity in Texas, New Mexico, and other states around the country, we’re disappointed but not surprised we now have several cases here in Ohio and known exposure in some counties,” Ohio Department of Health Director Dr. Bruce Vanderhoff said in a news release Tuesday.
Measles, a highly contagious infectious disease, can in some cases cause severe infections in the lungs and brain that may lead to cognitive issues, deafness or death. A vaccine against the illness is safe and effective, doctors and health officials say.
While most people’s symptoms improve, about 1 in 5 unvaccinated people who get measles will be hospitalized. About 1 out of every 1,000 children with measles will develop brain swelling that can lead to brain damage, and up to 3 of every 1,000 children who become infected will die, the CDC says.
So far, no cases in Kansas have led to hospitalization or death, according to the data from the state’s health department.
The Kansas cases come as other states are facing rising infections too. The majority of the cases have been reported in an outbreak in Texas that has sickened more than 400 people since late January and has caused the death of a child. An adult with measles also died in New Mexico.
Earlier this month, a person with a confirmed measles infection may have exposed Amtrak passengers on a train to Washington, D.C., according to officials at the D.C. Department of Health.
Measles cases have also been reported in a number of other states, including New Jersey, Georgia, California, Rhode Island, Kentucky, Michigan, Alaska and Pennsylvania.
The measles vaccine is usually administered in childhood as part of the measles-mumps-rubella, or MMR, shot. Two doses are about 97% effective at preventing measles, and a single dose is about 93% effective, the CDC says.
Similar to the Kansas cases, the Texas outbreak largely spread in a community with very low vaccination rates, and Texas health officials said the child who died in that outbreak was unvaccinated.