GENEVA, June 4 (Xinhua) -- The Swiss Federal Office of Public Health said Monday that the number of cases of hepatitis A recorded in Switzerland more than doubled in 2017, with men substantially more affected than women.

Statistics from the health office show that 110 instances of hepatitis A infection were reported in 2017, which is more than double that recorded in the 43 cases in 2016 and is at a level not seen since 2009 when 107 cases were recorded.

The office said that the rise is clearly connected to a wider outbreak of the disease across Europe, which has been particularly noticeable in men who have sex with other men.

Though in the Swiss case, "sexual contact" was only cited as an explicit infection source for 15 of the 110 cases, men were three times more likely than women to be affected. Males between the ages of 20 and 30 were most commonly infected. In previous years, the gender balance was rather stable.

Hepatitis A is an acute liver disease that can also be transmitted by ingesting certain foods or coming into contact with contaminated water. In general, the disease is more prevalent in countries with poor hygienic standards.

According to the World Health Organization, symptoms of hepatitis A, ranging from mild to severe, can include fever, malaise, loss of appetite, diarrhea, nausea, abdominal discomfort, dark-colored urine and jaundice.

Unlike hepatitis C, hepatitis A can be prevented by a simple vaccination. The health office recommends that those at higher risk of contraction should get the vaccination, including injection drug users, men who have sex with other men, those travelling to countries with poor sanitary conditions.