The measles outbreak that began in the South Plains region of Texas rose to 422 cases and spread to two new counties on Tuesday, according to health officials. The update from the Texas Department of State Health Services added 22 infections since the agency’s last update on Friday.

A local medical official is warning against the unsupervised use of vitamin A to treat measles as Texas sees a growing number of cases. Here's what to know.

The state health department reported 22 new cases of measles since last Friday's report. Forty-two of the patients have been hospitalized since the outbreak began in late January. The highest number of cases is in Gaines County where the outbreak is centered. The county has 280 of the 422 cases.