The US Centers for Disease Control and Prevention warned Wednesday that measles continued to spread across several states as the new school year approached, urging families to confirm children's vaccination status before term begins. The agency emphasised the risk to unvaccinated communities.

The warning followed confirmation that 2026 case totals had surpassed the previous year's figures. The CDC attributed the rise to declining measles-mumps-rubella immunisation rates in pockets of Texas, New Mexico and neighbouring states, where outbreaks have concentrated among school-age children.

The CDC recommended that children receive two doses of the MMR vaccine, which is about 97 per cent effective against measles. Public health departments in affected states opened additional immunisation clinics and issued guidance to schools on excluding unvaccinated students during active outbreaks.

Paediatricians and state health officers noted that measles spreads readily in classroom settings and can cause severe complications, including pneumonia and encephalitis. Several local health departments reported increased demand for catch-up vaccinations ahead of enrolment deadlines.

The CDC said it would continue tracking transmission through the late summer and coordinate with state agencies on outbreak response as students returned to classrooms across the country.