A major deep clean has been carried out on a Princess cruise ship where norovirus sickened more than 100 passengers and crew members last month.

The outbreak was reported on May 7, just over a week after the Caribbean Princess sailed from Port Everglades in Florida. A total of 145 passengers and 15 crew members reported symptoms such as diarrhoea and vomiting during the 14-night cruise.

According to the Centers for Disease Control, increased cleaning procedures were carried out in response to the outbreak. Samples were collected from the sufferers and everyone experiencing symptoms were asked to self-isolate to reduce the potential spread of the illness.

Norovirus is highly contagious and thrives in places where people gather at close quarters, which means cruise ships are particularly vulnerable. It may be contracted from an infected person or from contaminated food or water as well as by touching a contaminated surface.

Norovirus is particularly dangerous for the elderly because vomiting and diarrhoea can lead to dehydration and even death in extreme cases. Hand sanitisers are ineffective against the illness, but thorough hand washing can help to reduce the risk of cross-contamination.

The outbreak came only a matter of weeks after norovirus struck down another cruise liner from the same company. The Star Princess departed from Fort Lauderdale, Florida, on March 7 but 153 people were forced to self-isolate for much of the seven-night Caribbean cruise after falling ill on board. The ship underwent a rigorous deep clean before its next sailing.