LUBBOCK — A second unvaccinated school-aged child in West Texas died from a measles-related illness, a hospital spokesman confirmed Sunday, as the outbreak continues to swell.

Aaron Davis, a spokesperson for UMC Health System in Lubbock, Texas, said that the child was “receiving treatment for complications of measles while hospitalized” and did not have underlying health conditions. The hospital declined to say which day the child died.

Neither the U.S. Centers for Disease Control and Prevention nor the Texas State Department of State Health Services include the death in their measles reports issued Friday. Spokespeople for the state health department, the CDC and the U.S. Health and Human Services Department didn't immediately respond to requests for comment on Sunday.

A unvaccinated school-age child died in February in Lubbock — the first measles death in the U.S. in a decade. In early March, an adult in New Mexico who was unvaccinated and did not seek medical care became the second measles-related death.

Nationwide, the U.S. has more than double the number of measles cases it saw in all of 2024.

More than two months in, the West Texas outbreak is believed to have spread to New Mexico, Oklahoma and Kansas, sickening nearly 570 people. The World Health Organization also reported cases related to Texas in Mexico. The number of cases in Texas shot up by 81 between March 28 and April 4, and 16 more people were hospitalized. A team from the U.S. Centers for Disease Control and Prevention is on the ground in Texas assisting with outbreak response.

Health Secretary Robert F. Kennedy Jr., a longtime anti-vaccine activist, has delivered a tepid message on the importance of vaccination against measles, saying it should be encouraged while also sowing doubt in the vaccine’s safety. The measles, mumps and rubella vaccine has been used safely for more than 60 years and is 97% effective against measles after two doses.

Misinformation about how to prevent and treat measles is hindering a robust public health response, including claims about vitamin A supplements that have been pushed by Kennedy and holistic medicine supporters despite doctors’ warnings that it should be given under a physician's orders and that too much can be dangerous.

Doctors at Covenant Children's Hospital in Lubbock, where the first measles death occurred, say they've treated fewer than 10 children for liver issues from vitamin A toxicity, which they found when running routine lab tests on undervaccinated children who have measles. Dr. Lara Johnson, chief medical officer, said the patients reported using vitamin A to treat and prevent the virus.

Dr. Peter Marks, the Food and Drug Administration’s former vaccine chief, said responsibility for the death rests with Kennedy and his staff. Marks was forced out of the FDA after disagreements with Kennedy over vaccine safety.

“This is the epitome of an absolute needless death,” Marks told The Associated Press in an interview Sunday. “These kids should get vaccinated — that’s how you prevent people from dying of measles.”

Kennedy is expected to launch a Make America Healthy Again tour across the southwestern U.S. early this week.

Marks also said he recently warned U.S. senators that more deaths would occur if the administration didn’t mount a more aggressive response to the outbreak. Kennedy has been called to testify before the Senate health committee on Thursday.

Experts and local health officials expect the outbreak to go on for several more months if not a year. In West Texas, the vast majority of cases are in unvaccinated people and children younger than 17.

With several states facing outbreaks of the vaccine-preventable disease — and declining childhood vaccination rates nationwide — some worry that measles may cost the U.S. its status as having eliminated the disease.

Measles is a respiratory virus that can survive in the air for up to two hours. Up to 9 out of 10 people who are susceptible will get the virus if exposed, according to the CDC. The first shot is recommended for children ages 12 to 15 months, and the second for ages 4 to 6 years.