We would absolutely not take the MMR,” the mother of a six-year-old who died from complications stemming from the measles, told an interviewer.

As measles cases in West Texas are still on the rise two months after the outbreak began, local public health officials say they expect the virus to keep spreading for at least several more months and that the official case number is likely an undercount.

Vaccination efforts have faltered, and many residents have turned to alternative treatments endorsed by Robert F. Kennedy Jr., the health secretary.