Health experts in the Rio Grande Valley are among those monitoring a measles outbreak in West Texas.

While there are cases of measles in the Valley, most of the 58 confirmed infections — 45 — are in Gaines County, which is near the border with New Mexico.

Measles is highly contagious.

“If you cough inside a room and you leave, you could come in two hours later and you will breathe the air — and you will get measles if you're not vaccinated,” UTRGV pediatrics associate professor Cristel Escalona said.

READ MORE: West Texas measles outbreak climbs to 58, with four saying they were vaccinated

Measles symptoms include high fever, cough, red eyes and a rash all over the skin. Symptoms can become serious and even fatal, especially among children and those who are unvaccinated.

According to the Texas Tribune, 13 people with measles have been hospitalized, and this is Texas’ largest measles outbreak in more than 30 years.