(ANSA) - Florence, December 18 - Tuscan authorities on Wednesday issued a public health advisory on mixed berries after finding that 29 out of a total of 59 cases of Hepatitis A infection recorded in the region between May and September were due to eating virus-infected fruit. People wishing to consume mixed berries whether frozen or in sauces and jams must first boil them at 100 degrees for at least two minutes. Mixed berries in any shape or form must not be eaten raw or used as garnish on cakes, ice cream, and yogurt, public health officials said. An acute, non-fatal infectious liver disease, Hepatitis A is primarily spread when an uninfected (and unvaccinated) person ingests food or water that is contaminated with the faeces of an infected agent. The disease is closely associated with a lack of safe water, inadequate sanitation and poor personal hygiene, according to the World Health Organization. Of the 29 Tuscan cases, four were recorded in the Florence area, and one of these was due to eating virus-infected blueberries. Nationwide in the same period, health officials recorded 640 cases, 219 of them due to eating infected mixed berries.