In the midst of California’s ongoing hepatitis A virus (HAV) outbreak, health officials in the city of Los Angeles are now urging gay and bisexual men to get vaccinated for the liver virus, The Advocate reports.

Hepatitis A has killed 20 people and sickened more than 600 Californians since an outbreak began among San Diego’s homeless population last year. The outbreak has since prompted California’s governor to declare a state of emergency. Now, along with homeless people, first responders and law enforcement officials, men who have sex with men are considered to be at risk group.

L.A. County has seen 15 reported cases among those who are homeless or use recreational drugs, but now, health officials report that hepatitis A has impacted 14 gay and bisexual men across the county in a separate outbreak. They fear that this outbreak could spread to the local LGBT community, causing a major public health crisis.

Each year, gay and bisexual men account for nearly 10 percent of new hepatitis A cases across the United States. Local health authorities also warn that a police officer in the Los Angeles Police Department who works in the downtown Skid Row area, which is home to a significant homeless population, recently contracted the virus, indicating a potential spread among at-risk groups.

In order to prevent further infections, L.A. County’s health department is offering free hepatitis A vaccines at all of its clinics.