This summer, a deadly spike in hepatitis cases has health experts concerned.

They are not B and C cases that can cause life-ending liver damage, but hepatitis A cases, which are related to poor hygiene, and, typically, preventable.

At the end of last year, Arizona's Department of Health Services announced hepatitis A cases had quadrupled in a single month. By May, the numbers skyrocketed to 94 cases a month.

Jessica Rigler with the Department of Health confirmed more than 500 hep A cases, including six deaths, since the outbreak began.

Each year, she said Arizona sees a few hep A cases, but this strain is less about a food-borne contamination than it is living conditions.

"Primarily among people who use drugs or are experiencing homelessness or unstable housing," Rigler explained, "and, it's been spreading statewide."

The first case showed in Pima County and migrated north as transients moved to escape the summer heat.

Last month, the number of hep A cases dropped slightly in Arizona, as the outbreak hit nearly half the U.S.