Robert F. Kennedy Jr., the H.H.S. secretary, claimed that doctors had successfully treated children with unconventional remedies, including cod liver oil.

The measles outbreak that began in West Texas has now grown to 159 confirmed cases, the Texas Department of State Health Services announced on Tuesday afternoon. The case count, up from 146 cases on Friday,

As measles — a preventable disease the U.S. considered eliminated in 2000 — spreads through West Texas’ rural expanse, Klassen is sticking to an approach on vaccines that is a key tenet for Mennonites. Family leaders are the top decision-making authority — not outside recommendations, certainly not government mandates.