Vaccines work: Beware the Hep A in Denmark from Morocco

On 2 May 2018, Denmark reported a cluster of hepatitis A virus (HAV) infections with the subgenotype IA strain DK2018_231, through the European Centre for Disease Prevention and Control (ECDC)’s Epidemic Intelligence Information System (EPIS) for food- and waterborne diseases and zoonoses (FWD).

One of the three confirmed cases had travelled to Morocco. In response, five additional European Union (EU) countries (France, Germany, the Netherlands, Spain and the United Kingdom (UK)) reported cases (n = 20) infected with the same strain between 21 January and 10 April 2018.

Concurrently, Germany reported to EPIS that it observed more cases of hepatitis A with travel history to Morocco than expected, compared with the same period in the previous 5 years. Molecular analysis of the HAV VP1/P2A region revealed an unrelated cluster of the HAV subgenotype IB strain V18–16428. Cases infected with this unrelated strain were also reported from France, the Netherlands, Sweden and UK.

The appearance of clusters with a link to Morocco triggered further epidemiological investigations.

Two concurrent outbreaks of hepatitis A highlight the risk of infection for non-immune travelers to Morocco, January to June 2018



Martyna Gassowski, Kai Michaelis, Mirko Faber, Julie Figoni…