UC Davis Medical Center warns 200 people of possible measles exposure A single patient might have exposed others in the waiting room to measles.

A California hospital sent a warning to 200 people who may have been exposed to measles in the waiting room of its emergency department.

A patient who was diagnosed with measles was treated at UC Davis Medical Center in Sacramento, California, on March 17, according to a statement from Dean A. Blumberg, the chief of pediatric infectious diseases at UC Davis Children’s Hospital.

Blumberg said the hospital “took appropriate precautions in the areas the patient had visited” and that the patient was the only measles case the hospital had.

“In an abundance of caution, we’ve notified the 200 or so patients who we know may have been in the vicinity” of the patient, Blumberg said, adding that no other measles cases have emerged so far.

The letter warned the 200 people that they or a family member may have been exposed to measles while in the waiting room on March 17. It said they would “need to notify [their] primary health care provider(s) and [their] child’s provider(s) of this possible exposure to discuss [their] possible risk of infection, vaccination history, and other questions [they] may have.”

The patient diagnosed with measles was an unvaccinated child from Calaveras County, California, who developed the disease after returning from international travel, according to the Calaveras Health and Human Services Agency, Public Health Division.

The Centers for Disease Control and Prevention (CDC) describes measles as a disease that lives in the nose and throat and spread by coughing or sneezing. Measles can live in the air for two hours after someone with the disease coughs or sneezes. Outbreaks of the disease often begin when people become infected outside of the U.S. and then return but it is also easily spread in areas with people who haven't received the MMR vaccine.

The disease generally appears seven to 14 days after someone is infected, according to the CDC, with symptoms including high fever, cough, runny nose, red and watery eyes and rash with red spots. The CDC recommends two doses of the MMR vaccine for children aged 12 to 15 months and then another dose between 4 to 6 years old. Adults who haven't been vaccinated should also speak to their doctor about getting the MMR vaccine.

According to the CDC, there have been 387 measles cases confirmed across 15 U.S. states from Jan. 1 to March 28, 2019, surpassing the number of cases in the U.S. for all of 2018. According to the CDC, 387 cases is also the second highest number of measles cases to be confirmed in the U.S. since 2000, when the disease was considered eliminated.

The CDC has identified six ongoing measles outbreaks throughout the U.S., including in Washington, New York, and California.