From Norovirus To Hantavirus: Why Cruise Ships Face Serious Health Risks At Sea

Over 100 people have fallen ill with norovirus aboard Caribbean Princess cruise ship during a 13-day voyage. CDC confirmed the outbreak, and infected passengers were isolated while cleaning was increased. The ship will undergo full disinfection.

Norovirus outbreak affects over 100 people on cruise ship

A norovirus outbreak has affected more than 100 passengers and crew aboard the a. Health officials have confirmed the situation and say the ship is working closely with the US Centres for Disease Control and Prevention (CDC) to control the spread.

The outbreak comes at a time when another serious virus incident, involving hantavirus on a different ship, has already drawn global attention. 

These events have raised new concerns about how quickly diseases can spread in closed and crowded spaces like cruise ships.

What happened on the Caribbean Princess

The Caribbean Princess left Port Everglades in Fort Lauderdale on 28 April for a 13-day journey. The ship visited several destinations, including the Bahamas, Puerto Rico, Aruba, St Maarten, Curacao, and Bonaire.

During the voyage, 102 passengers and 13 crew members reported symptoms linked to norovirus. The CDC confirmed the outbreak.

The ship is scheduled to dock at Port Canaveral on Monday, 11 May.

What is norovirus?

Norovirus is one of the most common causes of food-related illness in the world. It spreads very easily and can infect people quickly, especially in crowded places. The virus spreads through:

• Contaminated food or drinks
• Touching infected surfaces
• Close contact with an infected person
• Sharing items such as utensils or handrails

Norovirus can survive on surfaces for several days. This makes it hard to remove if cleaning is not done properly and regularly.

Symptoms reported by passengers

The CDC says the most common symptoms in this outbreak are:

• Diarrhoea 
• Vomiting
• Fever
• Stomach cramps

These symptoms can appear suddenly and can spread fast in close environments.

Infected passengers were reportedly asked to stay in their cabins and quarantine. According to one passenger, those who are ill are being checked daily by medical staff.

Actions taken by cruise staff

After the outbreak began, Princess Cruises followed its outbreak response plan. The company said it took several steps, including:

• Increasing cleaning and disinfection across the ship
• Collecting stool samples for testing
• Isolating sick passengers and crew
• Consulting the CDC’s Vessel Sanitation Program

The company stated that all areas of the ship were disinfected and that extra cleaning continued throughout the voyage.

A company spokesperson said that before the ship reaches Port Canaveral, it will undergo full cleaning and disinfection again.

Passenger experience on board

Despite the outbreak, some passengers said they were still enjoying their trip while taking precautions.

One passenger said people should be careful when travelling in groups, as illness can spread easily.

Ship staff have kept guests informed about the situation. Passengers were told when new cases were reported and were updated about cleaning measures.

This open communication is important during outbreaks, as it helps reduce fear and confusion.

Why cruise ships are high-risk environments

Health experts often describe cruise ships as semi-closed spaces. This means people live closely together for long periods, with limited outside contact.

Unlike cities, where people return to different homes, cruise passengers:

• Eat together
• Use the same lifts and staircases
• Share entertainment spaces
• Spend time in theatres and dining halls

Modern large cruise ships can carry more than 6,000 passengers, plus over 2,000 crew members. This creates conditions similar to a floating city.

When one infected person boards a ship, the virus can spread quickly if not controlled.

Shared spaces and food services

Buffets and shared dining areas can increase the risk of spreading norovirus. If an infected person touches serving utensils or food surfaces, others may become ill.

Handrails, door handles, and elevator buttons are also common transmission points.

Because norovirus spreads even before symptoms appear, a person may feel healthy at the start of a trip and still pass the virus to others.

This makes early detection difficult.

Crew members and risk

Crew members can also spread illness. They often live in tighter quarters and work across many areas of the ship.

If a crew member feels unwell but does not report symptoms, the virus can spread further.

Experts say reporting illness quickly is essential to stopping outbreaks early.

Hantavirus outbreak on another ship

• The norovirus outbreak is separate from a serious hantavirus incident aboard the MV Hondius, a Dutch expedition ship. According to the World Health Organisation (WHO):
• Eight people connected to the outbreak became ill 
• Three people died 
• Four patients remained in hospital in South Africa, the Netherlands and Switzerland

The virus involved was the Andes strain of hantavirus, which is rare and can, in some cases, spread between humans.

Health officials believe the infection may have started before passengers boarded the ship, possibly during travel in Argentina or Chile, where the virus has been reported before.

This event has added to global concern about infectious diseases on ships.

Lessons from past cruise outbreaks

Cruise ships have faced health problems before.

During the Covid-19 pandemic in 2020, the Diamond Princess became one of the most studied outbreaks in maritime history.

Out of 3,711 people on board, more than 700 tested positive for coronavirus while the ship was quarantined off Japan.

The situation led to new health rules for cruise companies. These included:

• Stronger cleaning procedures
• Better air filtration systems
• Health screening before boarding
• Clear reporting systems

After the pandemic, cruise operators improved medical facilities and sanitation systems.

However, experts say the basic design of ships still makes disease spread possible.

Other diseases linked to cruise ships

Norovirus is not the only illness seen on ships. In the past, outbreaks of Legionnaires’ disease have occurred. This disease can grow in water systems, hot tubs, and plumbing.

One notable case in 1994 involved the Horizon cruise ship, where around 50 passengers were infected.

More recent investigations have focused on parts of water systems called “dead legs”, where water does not flow properly and bacteria can grow.

Cruise operators have since improved water safety systems.

Measles concerns

Health experts are also watching measles closely.

Measles spreads through the air and can stay in the air for hours after an infected person leaves a room.

If vaccination rates drop, the risk of outbreaks increases.

Cruise ships carry passengers from many countries. This can make them more vulnerable if diseases spread between travellers.

Role of the CDC's Vessel Sanitation Program

The CDC’s Vessel Sanitation Program monitors ships operating in US waters.

Ships are inspected regularly. If a ship scores below 85 during inspection, it fails health standards.

The programme also provides guidance during outbreaks, helping ships manage cleaning, reporting, and illness control.

Princess Cruises said it worked directly with this programme during the outbreak.

What happens next for the Caribbean Princess

When the ship reaches Port Canaveral, it will undergo full cleaning and disinfection before its next voyage.

Health officials will continue monitoring the situation to ensure no further spread.

Passengers who are ill are expected to remain isolated until they recover.