At least 30 passengers on an Italian cruise ship moored in Rotterdam have stomach complaints similar to the Norovirus, Dutch media said on Thursday.

Health service officials were called to the Aidaprima on Thursday morning after patients reported problems and no-one was allowed to come on board. The ship was later given the all clear, local broadcaster RTV Rijnmond said.

Norovirus is the most common cause of gastroenteritis and is highly infectious. There is no treatment for the disease, which is often spread through unhygienic food preparation.

The ship, which visits Rotterdam on a weekly basis during the summer, is currently moored close to the Erasmus bridge but will leave on Friday morning. It is carrying 3,500, mainly German passengers.