Hepatitis A is the mildest of the hepatitis viruses that affect humans. However, it can cause symptoms that last for several months in some people.
Unlike hepatitis B, which is transmitted via blood and sexual contact, hepatitis A is primarily a food-borne illness.
It can also be contracted directly from someone with the virus who does not wash their hands properly after being to the toilet.
Five of the 10 cases detected in the Republic to date have been linked to the consumption of frozen berries; the particular strain of the virus affecting people here is similar to that causing an outbreak in Italy.
The time from eating these infected strawberries, raspberries and blueberries until the onset of illness could be anything from 15 to 50 days.
Symptoms include high temperature, nausea and loss of appetite. Abdominal pain also occurs, along with a sense of fatigue.
These may be followed by jaundice, in which the skin and eyes go yellow due to excessive levels of a substance called bilirubin in the blood.
The virus attacks the liver, causing inflammation. As a result various liver enzymes are elevated; by measuring these through blood samples doctors can monitor the progress of the infection.
There is no treatment other than symptom management. There is a vaccine against the virus and this is recommended for people travelling to areas where it is endemic.
Almost everyone who gets hepatitis A recovers completely and does not develop any lasting liver damage, although they may feel sick for months.
In rare cases it can cause liver failure and death; this occurs more commonly in people over 50 and in those who already have other liver diseases such as hepatitis B or C.
