California’s outbreak of hepatitis A virus (HAV) is far from over and could continue for many months, even years, according to a recent update from federal health officials late last week, the Los Angeles Times reports. 

Thus far, the liver disease crisis has infected at least 569 people across San Diego, Santa Cruz and Los Angeles — cities that have officially declared local outbreaks. Additionally, 17 people have died since November 2016 as a result of the state’s hepatitis A crisis. The majority of victims have been homeless. 

Federal authorities have acknowledged that cities are taking major steps to control the crisis by, for example, administering hepatitis A vaccines to at-risk populations, installing public handwashing stations and cleaning city streets with bleach over the past few weeks. However, Monique Foster, MD a medical epidemiologist with the Centers for Disease Control and Prevention (CDC) nevertheless told reporters that the outbreak is likely to linger, potentially for up to two years.

The grim forecast has worried California health officials, who fear that the crisis could spread to even more cities in the meantime. Doctors also warn that new cases linked to the outbreak might not appear for weeks, as it can take up to 50 days for an infected person to show symptoms.

In an effort to prevent the hepatitis A outbreak from spreading even further, homeless outreach workers in San Francisco’s Tenderloin neighborhood have already begun offering vaccines to their clients. Health officials in Orange, Riverside and Sacramento counties also said they have begun ramping up their hep A vaccine programs and changing their sanitation protocols for local homeless encampments in an effort to stop the spread of the virus.