LOS ANGELES >> Los Angeles County public health officials said Thursday they are investigating an outbreak of seven measles cases, and they encouraged residents to ensure they are vaccinated.

Details about the patients or where they reside or work were not released, although health officials said most of cases “are epidemiologically linked.”

“Measles is a highly contagious viral disease that spreads from person to person through coughing or sneezing,” according to Dr. Jeffrey Gunzenhauser, the county’s interim health officer. “To protect individual health and to prevent the spread of measles to others, we urge residents who are not immunized to get the measles-mumps-rubella vaccine as soon as possible.

“Two doses of MMR vaccine is highly effective in preventing measles and is the best way to protect against disease,” he said.

In some cases, measles can lead to serious illness such as pneumonia, encephalitis or even death. Common symptoms include fever, runny nose, cough and a body rash.