Measles outbreak continues to worsen among kids in this US state

The agency first confirmed the outbreak on Feb. 5, and it has since been growing.

A Tuesday update stated that 58 cases have been identified within the last three weeks as symptoms occurred.

Forty-five measles cases have been reported in Gaines County; the others are spread across Terry County (9), Yoakum (2), Lubbock (1) and Lynn (1).

"Due to the highly contagious nature of this disease, additional cases are likely to occur in Gaines County and the surrounding communities," DSHS reported in the update on its website.

The agency added that the best way to prevent sickness is to receive two doses of the vaccine against measles, "primarily administered" as the combination measles, mumps and rubella (MMR) immunization.

Fox News senior medical analyst Dr. Marc Siegel commented on the threat of the spread.

"It is spreading and there are [58] cases, but there will be hundreds because the compliance rate with the vaccine in that part of Texas is just over 80%, and we need 95% for herd immunity," he told Fox News Digital.

"There is a 90% chance you will get it if you are unvaccinated and step into a room where someone with measles was two hours before," he cautioned.

"Texas in general is at risk - especially the unvaccinated and those who can't take a live virus vaccine because they are pregnant or immunocompromised."

The rise in cases comes more than two decades after health agencies reported that the disease was "eliminated" in 2000.

Symptoms usually appear within a week or two, and may include a high fever, cough, runny nose, and red, watery eyes. 

A few days later, flat, red spots appear on the face and then spread down the neck to the rest of the body. People are most contagious the four days before and four days after the rash appears.

Those who believe they may have measles or have been exposed should self-isolate and call their doctor before arriving to be tested, according to the DSHS. 

Fox News Digital's Alexandra Koch contributed to this report.