A new day, a new cruise ship, and a new virus that has infected 115 people so far. Just days later, the Hantavirus outbreak linked to a Dutch cruise ship that killed three people, novovirus, has created a frenzy on a Caribbean Princess cruise ship.

This is not a an unknown virus and marks the fourth gastrointestinal outbreak on a cruise ship in the last few months. The incident highlights a persistent challenge of managing contagious viruses in confined marine environments.

Why are cruise ships prone to virus outbreaks?

Cruises, functioning as floating hotels, are often sold to us as one-stop holiday destinations full of recreational fun. You can enjoy everything, from good food to relaxing spas, or thrilling waterpark adventures. These functionally well-connected spaces become dangerous, too. Once a virus enters on board. It can spread across the entire ship in no time.

The ship's design adds to the problem. Buffet-style dining rooms, bars, lifts, theatres, and spa areas are mainly indoors and shared by a large number of people. Their touching the same surfaces and using shared utensils makes it easy for a virus to spread rapidly.

Studieshave also shown that illnesses can easily spread if the cruise ship spaces are not well ventilated. Special filters and air-purifying gadgets play a key role in keeping passengers safe.

Hantavirus vs Norovirus

Hantavirusis an animal-borne virus in which rodents like rats and mice act as the natural reservoir. Humans can get infected when exposed to rodent urine, saliva, or droppings, particularly in enclosed spaces.

It can be transmitted while cleaning rodent-infested areas, where contaminated dust particles can be inhaled. Unlike other respiratory viruses such as COVID-19, hantavirus does not spread easily through human interaction. Human-to-human transmission is extremely rare. It has been documented in parts of Argentina and Chile where prolonged close contact among household members was involved.

Meanwhile, Norovirus is a more contagious virus that can cause acute gastroenteritis, an inflammation of the stomach or intestines, according to the Centres for Disease Control and Prevention (CDC). People of all ages can get infected during norovirus outbreaks. It causes millions of cases of foodborne illnesses every year and remains one of the most common causes of vomiting and diarrhoea globally.

It can spread very easily by touching infected surfaces, sharing food or utensils, and having direct contact with someone with norovirus. A norovirus-infected person can feel extremely ill, and vomit or have diarrhoea many times a day. This can lead to dehydration (loss of body fluids), especially in young children, older adults, and people with other illnesses.