There was a suspected outbreak of the rare hantavirus aboard a cruise ship. But don’t panic: Based on current research, the likelihood that this spreads significantly is very low. Still, here’s what you need to know to protect yourself.

Three are dead, and others had been infected on the Dutch ship, MV Hondius. Since docking, when passengers were allowed to leave the ship, several other cases have been confirmed, according to the World Health Organization.

As of now, there is very little conclusive evidence of documented cases of human-to-human spread of the hantavirus by researchers. Hantavirus is usually spread by infected rodents’ urine or feces, which can lead to severe respiratory illness, kidney failure, hemorrhagic fever or death.

The Andes virus, which was laboratory-confirmed for some of these cases, is the only hantavirus type known to spread human-to-human.

According to the World Health Organization, the working hypothesis is that the first case was acquired through exposure on land before boarding the cruise. Current evidence suggests there may have been human-to-human transmission on the ship after that.

"Hantavirus doesn't spread as readily in dry environments," Dr. Allison Edwards, a family physician, said. "Wetter weather in an area that already is prone to having a hantavirus spread is going to be more problematic."

The best precaution to take is to minimize contact with rodents and immediately see a doctor if you feel sick after exposure.

"Hantavirus is a virus that can cause a pretty extreme inflammatory reaction within the body that can lead to lung failure, sometimes renal failure or kidney failure," Edwards said.

Early symptoms of the illness are similar to those of other viruses and can easily be confused with the flu.

Early Stage Symptoms:

• fatigue
• fever
• muscle aches
• nausea, vomiting, diarrhea

"People initially present by feeling like maybe a little bit feverish, maybe like they're coming down with something, and after a couple of days, it can get markedly worse," Edwards said.
Four to ten days after early-stage symptoms, respiratory symptoms may develop, and 38% of people who develop these symptoms may die, according to the CDC.

Late Stage Symptoms:

• coughing
• shortness of breath
• tightness in the chest

Historically, the likelihood of contracting hantavirus at home, while traveling or on a cruise is extremely low.

"At no point do we ever want anybody to panic in medicine," Edwards said.

The World Health Organization maintains that it is rare in humans and not easily transmitted.

The case of this ship remains under close monitoring.

weather.com content writer Ada Wood enjoys exploring the stories that science and climate teach us about our natural world and how it influences the way we live in it.