Hantavirus has been all over the news lately due to a shocking outbreak on the MV Hondius cruise ship in the Atlantic Ocean.
The virus is typically transmitted to humans when they breathe airborne particles from the dried droppings, urine or saliva of infected rodents. That’s how Oscar winner Gene Hackman’s wife, Betsy, died last year.
The cruise ship culprit appears to be the Andes virus, the most common cause of severe hantavirus in South America. What makes the Andes strain unique among hantaviruses is that while it’s primarily transmitted to humans from infected rodents, it can be spread from person to person.
As of Wednesday evening, three of the ship’s passengers have died and several others have fallen ill from the virus.
Hantavirus isn’t the only zoonotic disease — in fact, the World Health Organization reports that roughly 60% of emerging infectious diseases are zoonoses.
You’ve probably heard of rabies, Lyme disease (comes from ticks), bird flu and West Nile virus (mosquitoes). Here’s a look at four emerging deadly diseases that spread between animals and humans.
Nipah virus
Humans can pick up Nipah virus via contact with infected fruit bats or pigs or consumption of raw date palm sap contaminated with bat saliva or urine.
Symptoms like fever, headaches, muscle pain, vomiting and sore throat typically emerge four to 14 days after exposure.
The virus is highly deadly — it has a fatality rate of 40% to 75%.
India has been a hotspot for Nipah cases, including two nurses who got infected in 2025. The country was able to avoid a large-scale outbreak last year even as Nipah can be transmitted between people.
Marburg virus
Beware the Egyptian fruit bat, which has made its home in Africa, the Middle East and the Mediterranean. The cave-dwelling creature sheds the virus through saliva, urine and feces.
Symptoms often appear two to 21 days after exposure, with eight to 10 days being the most common timeframe for onset.
“Dry” symptoms include high fever, headache, malaise and muscle aches, while nausea, vomiting and diarrhea are “wet” symptoms.
The fatality rate ranges from 24% to 88%.
A Marburg outbreak that lasted from November to January left nine people dead in Ethiopia.
Mpox
As if you need another reason to stay away from giant-pouched rats, they can carry mpox, formerly known as monkeypox.
Rope squirrels and African dormice are other mpox miscreants that can infect humans when they bite or scratch or serve as dinner.
Flu-like symptoms — think fever, chills, headaches and exhaustion — tend to show up three to 21 days after exposure. A distinct rash consisting of fluid- or pus-filled bumps makes its appearance shortly thereafter.
Most people fully recover in two to four weeks. The disease can be deadly in people with weakened immune systems, young children and pregnant women.
The CDC has identified 20 cases of the clade I strain of mpox in the US since November 2024, most due to travel to Central and Eastern Africa or Western Europe.
Crimean-Congo hemorrhagic fever
Just when you thought Lyme disease was the worst that ticks had to offer, meet Crimean-Congo hemorrhagic fever (CCHF).
It’s a viral disease transmitted by bites from Hyalomma ticks (primarily found in Asia, Europe and North Africa) or contact with infected livestock blood or tissues.
High fever comes on suddenly, as well as headaches, joint, muscle and stomach pain and vomiting.
In severe cases, there can be significant bleeding and kidney failure. Fatality rate can range from 30% to 50%.
CCHF is endemic in Uganda, which reported a case this year involving a young male nurse.
