EXPLAINER: What is the rare hantavirus Andes strain?

The National Institute for Communicable Diseases of South Africa confirmed that it is the rare Andes strain of the hantavirus that was identified among several victims on the stranded luxury cruise ship that had 150 passengers onboard and was on its way to Cape Verde.

According to the World Health Organization (WHO), the first case of hantavirus onboard the MV Hondius may have been afflicted with the pathogen even before boarding the ship.

The passenger vessel left Ushuaia, Argentina last April 1.

The WHO, which was alerted Saturday to a rare but deadly outbreak of hantavirus aboard the Hondius, has determined that the first of three people to die must have been infected before boarding the ship.

Out of eight confirmed and suspected hantavirus cases, a 70-year-old Dutch passenger was the first to fall ill after showing symptoms such as showing symptoms including fever, headache and mild diarrhea.

The passenger developed respiratory distress on April 11, dying on board the same day.

The incubation period or the time between infection and the onset of symptoms usually takes between two to three weeks. So the patient could not have been infected on the ship, or on one of the islands the ship visited.

What is the Andes strain of the hantavirus?

According to WHO, the hantavirus is part of the Family Hantaviridae under the Order Bunyavirales.

There is a particular type of rodent that serves as a reservoir of the hantavirus.

The hantavirus remains in the animal, which does not exhibit symptoms of the disease.

The hantaviruses found in North, Central, and South America is known to cause Hantavirus Cardiopulmonary Syndrome (HCPS). Among the strains of the hantaviruses is the Andes strain.

The Andes strain is known to cause rare human-to-human transmission, particularly in Argentina and Chile.

It is difficult to identify the hantavirus because its symptoms are similar to those afflicted with the flu virus, COVID, and dengue.

The fatality rate of the Andes strain is at 40%, according to the WHO.

The hantavirus is commonly spread among infected rodents through urine, feces, and saliva.

So far, the only documented Andes virus can be found in America with a rare human-to-human transmission.

If human-to-human transmission occurs this is usually through close and prolonged contact with an infected person, particularly household members or intimate partners especially during the early phase that is highly contagious.

The Centers for Disease Control and Prevention (CDC) said there is no medicine nor vaccine for hantavirus infection.

Suspected HPS patients should immediately be given emergency medical care and it is better to bring the patient to the Intensive Care Unit even without a confirmation diagnosis.

There are ways to avoid hantavirus infection, these are: pest or rodent control; avoid contact with the urine, feces, saliva, and nest of rodents.

According to the WHO, the following steps can also be helpful:

• Keep the house and workplace clean
• Close the hole wherein rodents could enter
• Store food properly
• Safely clean contaminated areas
• Avoid dry sweeping rat droppings
• Wet the area before cleaning
• Make it a habit to wash hands

Contract tracing will continue for the passengers of MV Hondius, wherein 62 cases have been identified as close contacts as of May 6, 2026, according to the Ministry of Health of South Africa.

They will be monitored until the end of the hantavirus incubation period.

WHO officials underscored that hantavirus infection has low risk to the public. — BAP, GMA News