Norovirus vs hantavirus explained: Key differences to know after 115 fall ill on Princess cruise ship

Caribbean Princess cruise ship departed Port Everglades in Fort Lauderdale on April 29 and is scheduled to arrive at Port Canaveral on May 11.

A norovirus outbreak aboard the Caribbean Princess has sickened more than 100 passengers and crew members during a 13-night Southern Caribbean voyage, according to the US Centers for Disease Control and Prevention (CDC).

Norovirus is relatively common and typically causes short-term gastrointestinal illness, while hantavirus is rare and potentially life-threatening. (UnSplash)

The ship departed Port Everglades in Fort Lauderdale on April 29 and is scheduled to arrive at Port Canaveral on May 11.

According to the CDC, 102 of the ship’s 3,116 passengers reported falling ill during the voyage. An additional 13 crew members out of 1,131 onboard also became sick.

The predominant symptoms reported were diarrhea and vomiting, which are commonly associated with norovirus infections.

In response to the outbreak, the cruise ship increased cleaning and disinfection procedures, while those who became ill were isolated from unaffected travelers to help limit further spread.

Norovirus vs. hantavirus: What’s the difference?

The outbreak aboard the Caribbean Princess has also sparked confusion online between norovirus and hantavirus. These are two very different illnesses.

While norovirus is relatively common and typically causes short-term gastrointestinal illness, hantavirus is rare and potentially life-threatening.

Concerns about hantavirus recently surfaced after reported illnesses linked to the expedition cruise ship MV Hondius.

Here’s how the two viruses differ:

1. Cause and transmission

Norovirus

Norovirus is a highly contagious virus that spreads primarily through contaminated food or water, infected surfaces, or direct person-to-person contact. The virus thrives in crowded environments such as cruise ships, schools, nursing homes, and restaurants. It can survive on surfaces for days..

Hantavirus

Hantavirus is carried by rodents, including mice and rats. People typically become infected after inhaling airborne particles contaminated with rodent urine, droppings, or saliva. Unlike norovirus, hantavirus does not usually spread through casual human contact.

2. Symptoms and onset

Norovirus

Symptoms often begin suddenly and may include:

1. Vomiting
2. Watery diarrhea
3. Nausea
4. Stomach cramps
5. Mild fever, headaches, or body aches

The incubation period is usually between 12 and 48 hours, and most people recover within one to three days.

Hantavirus

Early symptoms resemble the flu and may include:

1. Fever
2. Severe fatigue
3. Muscle aches
4. Headaches and dizziness

In serious cases, the illness can progress to severe breathing problems as fluid builds up in the lungs. Some strains may also affect the kidneys.

Symptoms can appear anywhere from one to eight weeks after exposure, with many cases developing after about two weeks.

3. Severity and health risks

Norovirus

Although unpleasant, norovirus is rarely fatal. The biggest risk is dehydration, especially among older adults, young children, and people with weakened immune systems.

Hantavirus

Hantavirus infections are far rarer but significantly more dangerous. There is no specific antiviral treatment, and patients often require intensive supportive care, including oxygen therapy. According to AP, the syndrome is fatal in about 35% of people infected.