The individual—whose name, age, and sex were not released by local authorities—is the second person to die from the virus amid a growing outbreak along the New Mexico-Texas border, sparking widespread concern among doctors that the federal government’s response is simply not enough to halt the spread of measles.

A measles outbreak in the American southwest has killed a second person, an unvaccinated adult, New Mexico health officials have said. The fatality comes roughly a week after measles took the life of an unvaccinated child in nearby Texas,

A n adult who was infected with measles has died in New Mexico, state health officials announced Thursday, though the virus has not been confirmed as the cause. The person who died was unvaccinated and did not seek medical care,

As measles cases climb nationwide, health officials are reporting a second recent death of an unvaccinated adult in New Mexico who tested positive for measles after passing, but the official cause of death is still under investigation.