LAS VEGAS (AP) — Health officials in southern Nevada say the number of acute hepatitis A cases has risen drastically.

The Southern Nevada Health District said this week that 37 cases have been reported in Clark County between Jan. 1 and May 31. Seventeen cases were reported in 2018, none in 2017 and six in 2016 during the same timeframe.

Health officials say people who are using drugs or who don't have a home are at increased risk.

The disease is transmitted by oral contact with fecal matter, even in microscopic amounts. It attacks the liver and causes symptoms including abdominal pain, nausea, diarrhea, fever and jaundice.

Health officials say good hygiene and vaccinations are the best preventative measures.