According to KPCC, the Los Angeles Public Health Department announced that an “outbreak” of seven measles cases has been confirmed this month. Health officials say all seven of the unidentified individual were not vaccinated.

From KPCC:

The department “is classifying this as an outbreak,” it said, adding that the first person who got sick developed symptoms in late November. Since then, the agency said, there has been “one wave” of additional cases.

Details surrounding the cases are not being released due to privacy concerns, but health officials noted that “most of the cases” are “epidemiologically” linked.

Health officials are closely monitoring the situation for new outbreaks.

“Some exposures may have occurred in public locations,” Public Health officials said, adding that it’s investigating those cases.

KPCC reports that if the department “can identify and contact all people who might have been exposed to the virus, it will not release information about these locations, it said. But the agency says if it can’t reach everyone, it will release that information to the public.”

Measles symptoms usually include fever, runny nose, cough and a rash all over the body. In some cases, measles can cause pneumonia, encephalitis or death. The disease can live for up to two hours in an area where an infected person has coughed or sneezed.

The disease is highly contagious and an infected person can infected 90 percent of unvaccinated people they come into contact with. A person can develop measles up to 21 days after being exposed.