A second school-age child who was hospitalized with measles is the third measles-related death in the U.S. since the virus started ripping through West Texas in late January.

The child died Thursday, according to state health officials. The child was 8 years old, according to a statement from Health Secretary Robert F. Kennedy Jr. A spokesperson for UMC Health System in Lubbock, Texas, confirmed the child was unvaccinated and being treated for measles complications.

The U.S. now has more than double the number of measles cases it saw in all of 2024, with Texas reporting another large jump in cases and hospitalizations on Friday. Other states with active outbreaks — defined as three or more cases — include New Mexico, Kansas, Ohio and Oklahoma. The virus has been spreading in undervaccinated communities.

The multistate outbreak confirms health experts’ fears that the virus will take hold in other U.S. communities with low vaccination rates and that the spread could stretch on for a year. The World Health Organization said last week that cases in Mexico are linked to the Texas outbreak.

Measles cases also have been reported in Alaska, California, Colorado, Florida, Georgia, Kentucky, Maryland, Michigan, Minnesota, New Jersey, New York, Pennsylvania, Rhode Island, Tennessee, Vermont, and Washington.

The U.S. Centers for Disease Control and Prevention defines an outbreak as three or more related cases. The agency counted six clusters that qualified as outbreaks in 2025 as of Friday.

In the U.S., cases and outbreaks are generally traced to someone who caught the disease abroad. It can then spread, especially in communities with low vaccination rates. In 2019, the U.S. saw 1,274 cases and almost lost its status of having eliminated measles. So far in 2025, the CDC’s count is 607.

Measles is caused by a highly contagious virus that’s airborne and spreads easily when an infected person breathes, sneezes or coughs. It is preventable through vaccines, and has been considered eliminated from the U.S. since 2000.

Here’s what else you need to know about measles in the U.S.

Do you need an MMR booster?

The best way to avoid measles is to get the measles, mumps and rubella (MMR) vaccine. The first shot is recommended for children between 12 and 15 months old and the second between 4 and 6 years old.

People at high risk for infection who got the shots many years ago may want to consider getting a booster if they live in an area with an outbreak, said Scott Weaver with the Global Virus Network, an international coalition. Those may include family members living with someone who has measles or those especially vulnerable to respiratory diseases because of underlying medical conditions.

Adults with “presumptive evidence of immunity” generally don’t need measles shots now, the CDC said. Criteria include written documentation of adequate vaccination earlier in life, lab confirmation of past infection or being born before 1957, when most people were likely to be infected naturally.

A doctor can order a lab test called an MMR titer to check your levels of measles antibodies, but health experts don’t always recommend this route and insurance coverage can vary.

Getting another MMR shot is harmless if there are concerns about waning immunity, the CDC says.

People who have documentation of receiving a live measles vaccine in the 1960s don’t need to be revaccinated, but people who were immunized before 1968 with an ineffective measles vaccine made from “killed” virus should be revaccinated with at least one dose, the agency said. That also includes people who don’t know which type they got.