Health officials in Los Angeles are investigating a cluster of measles cases that has infected seven as of a December 23rd report by The LA Times.

Officials wouldn’t say where in the county the infected patients lived, other than that they weren’t in Pasadena or Long Beach, which report cases separately because they have their own health departments.

The disease is highly contagious and those unvaccinated have a high to certain risk of contracting the virus if they come in contact with it. Health officials are recommending vaccinations for anyone not already inoculated against measles.