The nation’s second largest hepatitis A outbreak in the last 20 years could keep going for months, if not even years, according to health officials

There are at least 569 people who have been infected so far while 17 others have died of the virus since November in San Diego, Santa Cruz and Los Angeles.

Medical epidemiologist, Dr. Monique Foster, told reporters that this outbreak could linger in spite of the prevention efforts.

“It’s not unusual for them to last quite some time — usually over a year, one to two years,” Foster said.

As expected, this forecast has got health officials all over the state of California worried, and even in states where there haven’t yet been cases.

Many are starting to offer vaccines to their homeless people, as they are consider to be more at risk. Doctors also say that those with hepatitis A could travel and infect people in a new community without even realizing it, creating more outbreaks.

Hepatitis A is most commonly transmitted through contaminated food. Unsanitary conditions make it more likely to spread. California’s outbreak is spreading from person to person, especially in homeless communities.

“The general population — if you’re not in one of those specific risk groups — is at very low risk, and we’re not recommending vaccinations,” he said.