An outbreak of meningitis has been discovered on MSC Cruises’ ship MSC Orchestra in Livorno, Italy.

The line confirmed that four crew members were diagnosed with bacterial meningitis on Sunday. Two are in a serious condition.

They are receiving medical treatment in Livorno’s main hospital.

All passengers who were on board the 3,000-capacity ship when it called at the Italian port on Sunday received an antibiotic treatment as a precautionary measure, the line said.

The company is also contacting all passengers who were on board MSC Orchestra during the past seven days, advising them to take antibiotic treatment as an “extra precaution”.

The ship sailed to Valencia yesterday and was inspected by Spanish health authorities.

It was subsequently released as fully compliant with international maritime health and safety regulations, MSC Cruises said.

The line’s head of corporate medical services Pierfrancesco Lepore said: “No additional crew members and no guests have presented with symptoms.

“The situation on board MSC Orchestra is under control and an MSC Cruises medical taskforce is currently on board to closely monitor the situation and ensure that all necessary procedures are followed.”

No information was given as to the source of the illness.