The number of measles cases in Pinal County, Arizona has risen to 13 after the Arizona Department of Health Services announced the confirmation of two additional cases on Thursday.


The measles cases originated in the private Eloy Detention Center when a detainee with measles was brought in.  This investigation is ongoing.

“The trouble with measles is that people are contagious before they know they have it — which can result in exposure to others,” Dr. Cara Christ, director of the Arizona Department of Health Services, wrote in a blog post.

The Arizona outbreak even prompted Alabama health officials to urge vaccination after it was discovered earlier this week that four people who came to Alabama had possible exposure to measles linked to to Arizona.

As of Tuesday morning, the Alabama Department of Public Health (ADPH) determined that these four people do not have signs of measles, but they will be vaccinated and monitored for 42 days for any illness.

Related: How contagious is measles? Answer: Very

Measles is a highly contagious respiratory disease caused by a virus. Measles can stay airborne or live on surfaces for up to two hours. Symptoms include fever, runny nose, cough and a rash all over the body. Those infected can transmit the virus for about five days before the typical rash appears. Symptoms occur within one to two weeks after exposure. Measles is so contagious that any child who is exposed to it and not vaccinated will probably get the disease.

Common complications of measles are ear infections and less often pneumonia. Rarer complications are inflammation of the brain and death.

Routine MMR vaccination is recommended for all children, with the first dose given at age 12-15 months, and a second dose at age 4-6 years. Unless they have other evidence of immunity, adults born after 1956 should get at least one dose of MMR vaccine. Two appropriately spaced doses of MMR vaccine are recommended for health care personnel, college students and international travelers.