There has been 950 confirmed cases of hepatitis A across Europe since September 29, warned the European Center for Disease Prevention and Control (ECDC).
Twenty two countries were affected by the outbreak, including England, Wales, France, Germany and Italy.
Since the outbreak started in June 2016, 3,813 cases of hepatitis A have been confirmed. March 2017 had the highest number of reported cases so far, with 507, ECDC said.
The viral infection was mainly affecting “men that have sex with men”, added the European health watchdog.
“As of December 18 2017, the monthly number of laboratory-confirmed cases remain significantly higher than in previous years,” said ECDC.
“Although decreasing in its intensity, the outbreak is still ongoing.
“More cases associated with this event are to be expected in EU/European Economic Area countries in the coming months.”
In September, ECDC reported nine times as many men were infected by hepatitis A than women.
But, over the past three months, only six times as many men were infected.
“A considerable increase in the total number of hepatitis A cases in women has also been observed, with outbreak strains circulating in this group, too,” it said.
Hepatitis A is a liver infection, caused by a virus that’s spread in the faeces of an infected person, according to the NHS.
Symptoms of the condition include yellowing of the skin and eyes, fatigue, joint pain, fever, and vomiting.
In rare cases, the virus can cause liver failure, and may be life-threatening.
The NHS urges people to see their GP if they have symptoms of hepatitis A, or have been exposed to the virus recently.
The most at-risk people in the UK can be vaccinated against hepatitis A.
The infection can be spread to other people by eating food prepared by someone who has the condition, and hasn’t washed their hands properly, the NHS warned.
Eating raw shellfish, drinking contaminated water, or having sex with someone who has the infection also increases the risk of infection.
Hepatitis A patients are most at risk from infection around two weeks before their symptoms appear.
The symptoms usually pass within a couple of months.
Last month, 180 people at a Wales school were offered the hepatitis A vaccination, after a student was diagnosed with the infection.
Seven people in the student’s family were confirmed to have the condition.