Do you need a measles booster shot? What to know as a U.S. outbreak spreads

A measles outbreak in the U.S. has grown to nearly 100 cases, prompting questions about how to stay safe. The outbreak is primarily affecting children and teenagers in Texas, nearly all of whom were unvaccinated. Nine cases have been reported in New Mexico.

The Texas health department has reported at least 16 hospitalizations in the outbreak, as of Feb. 21. In some cases, measles can cause severe infections in the lungs and brain that can lead to cognitive issues, deafness or death.

While measles is one of the most contagious infectious diseases, doctors say the vaccine, normally given as part of the combination measles-mumps-rubella (MMR) vaccine, is highly effective and safe.