In 2018, well being authorities in southern Argentina have been racing, attempting to grasp what had triggered practically three dozen individuals in the tiny village of Epuyen to fall gravely ailing. By the finish of the outbreak, 11 of them had died.
Their sickness, which triggered many to be admitted to intensive look after pneumonia and extreme respiration issues, was brought on by the Andes virus, a pressure of rodent-carried hantavirus able to being transmitted from individual to individual. It is the identical virus that’s believed to have sickened eight passengers touring on the MV Hondius cruise ship, which is crusing to a port in the Canary Islands.
Before the Epuyen outbreak, little or no was recognized about the Andes pressure, mentioned Dr. Gustavo Palacios, a microbiologist at the Icahn School of Medicine at Mount Sinai in New York.
“There is very limited experience handling this virus,” mentioned Palacios, who was the director of the Center for Genome Sciences at the US Army Medical Research Institute of Infectious Diseases when he helped piece collectively how the virus moved from individual to individual. The study of the outbreak was revealed in 2020 in the New England Journal of Medicine.
“Probably we are having less than – I don’t know, I’m giving you a number, just for a ballpark number – 300 cases in history,” Palacios mentioned, including that he’s additionally a part of a gaggle of consultants advising on the ongoing cruise ship outbreak.
Based on their investigation of the Epuyen outbreak, which concerned three separate superspreader occasions – the place a single particular person handed the an infection to a number of others – Palacios mentioned the window for transmission of the Andes virus seems to be brief, about a day. People are at their peak of infectiousness on the day they develop a fever.
But the research additionally discovered that the virus could possibly be handed comparatively simply throughout this window, after durations of solely temporary proximity to another person.
The researchers have been capable of present that the first affected person, a 68-year-old man who attended a celebration with about 100 different individuals, contaminated another person after being in touch with them for only some moments, on the technique to the restroom.
The index case — the first documented case — in the Epuyen outbreak is believed to have been contaminated close to his residence. In Argentina, the Andes virus is carried by long-tailed pygmy rice rats, that are widespread in agricultural areas and may dwell round homes.
Around the world, together with in the US Southwest, rodents are recognized to harbor hantaviruses. Humans are usually contaminated by contact with their urine, feces or saliva, generally when the virus turns into aerosolized throughout cleansing.
Most just lately, hantavirus made information in the US in 2025 after an post-mortem decided that Betsy Arakawa, the spouse of actor Gene Hackman, had died of the virus.
In most instances, hantaviruses end in what’s known as a dead-end an infection: A human will get contaminated after contact with animal droppings however doesn’t move it on to anybody else.
Andes virus is an exception, nevertheless. It can unfold between individuals, giving it the potential to spark outbreaks.
While the World Health Organization says the risk posed from the present outbreak on the cruise ship Hondius is low, WHO has classified hantaviruses as rising precedence pathogens with excessive potential to spark worldwide public well being emergencies due to how critical these infections might be. Hantavirus an infection might be deadly in up to 40% of cases.
Through cautious investigative work, scientists decided that the first affected person in Epuyen attended a celebration on November 3, 2018, the identical day he ran a fever.
During the 90 minutes he was at the occasion, he contaminated 5 others, together with two individuals sitting roughly a foot from him at the identical desk and two individuals who have been sitting roughly 4 ft away from him at neighboring tables. The fifth particular person to catch the virus crossed paths with the affected person solely briefly on their technique to the restroom.
Another complication with the Andes virus is its lengthy incubation interval, that means the time between an individual’s publicity to the virus and once they first start to indicate signs. The lengthy interval makes monitoring down individuals who might have been uncovered notably tough.
Although all 5 sufferers have been uncovered at the November 3 celebration, they didn’t begin to present signs for one more two to 3 weeks.
The second affected person in the outbreak, a 61-year-old man described as having an energetic social life, contaminated six others earlier than he died, 16 days after first displaying signs.
His spouse, who attended his wake with a fever, contaminated 10 others, who all turned sick between 17 and 40 days after attending that occasion.
An further 12 individuals have been contaminated after contact with beforehand contaminated sufferers.
In the Epuyen outbreak, greater than 80 healthcare employees have been uncovered to sufferers with signs, however none was instantly contaminated themselves, although only a few used any private protecting gear. There have been two contaminated healthcare employees at the native rural hospital, a smaller facility, which can have been the first to see sick sufferers.
The restricted unfold amongst healthcare employees in the Epuyen outbreak speaks to the brief window of time that an individual could also be infectious, consultants mentioned.
“This is not Covid. This is really not Covid. It’s not even influenza. It’s an unusual person-to-person event, and it might have happened because, perhaps, of a closed environment on a ship,” mentioned Dr. Lucille Blumberg, an infectious illness specialist who’s the former deputy director of the National Institute for Communicable Diseases in South Africa, of the cruise ship outbreak.
Blumberg was consulted Friday about the deaths associated to the Hondius and one other significantly ailing passenger who had been on a unique a part of the ship, who was medically evacuated to Ascension Island, a British territory that sits in the Atlantic Ocean about a thousand miles from the west coast of Africa, after which flown to South Africa. He is intensive care on a ventilator however is bettering, Blumberg mentioned.
She mentioned they’d be following the passengers on the Hondius intently. They will every have to be monitored for no less than 45 days, she mentioned.
On Wednesday, the World Health Organization confirmed {that a} man in Switzerland had examined optimistic for the virus after getting off the Hondius and flying residence.
Contact tracing is underway for individuals who have been on flights with ailing passengers from MV Hondius. Oceanwide Expeditions, the cruise operator, mentioned it’s nonetheless engaged on the particulars of who embarked and disembarked from the ship since March.
“We expect to share details on that in the coming days,” mentioned Piet Hein Coebergh, a spokesperson for the firm, which is predicated in the Netherlands.
So far there are eight sicknesses linked to the ship, three confirmed instances of hantavirus and 5 suspected instances, in accordance with WHO.
“People come off and on at the ports,” Blumberg mentioned. “They don’t keep for the complete voyage.
“I think we’ll see other cases,” she mentioned.
Many of the passengers have been critical birdwatchers who had been on expeditions in South America earlier than becoming a member of the cruise, Blumberg mentioned.
For that purpose, avian influenza was considered one of her preliminary guesses as to the reason for the sicknesses. She additionally suspected that folks might need legionella infections, which may trigger pneumonia.
After two rounds of checks have been unfavourable for these and different suspected pathogens, Blumberg mentioned, she known as the lab at the Centre for Emerging Zoonotic and Parasitic Diseases at the National Institute for Communicable Diseases and instructed them to check for hantavirus.
After it was optimistic, she known as the hospital that had handled the ailing spouse of the first passenger, who died, and requested whether or not it had saved any take a look at tubes of her blood. It had, and that affected person, too, examined optimistic posthumously for hantavirus. By Monday, gene sequencing decided that it was the Andes pressure.
Blumberg mentioned that for herself and her colleagues, it has been a round-the-clock effort; she was up at 4 a.m. Wednesday. She mentioned they’re actively engaged on tracing the contacts of sufferers who have been evacuated to South Africa for medical care. They are additionally engaged on sequencing the whole genome of the virus, which ought to assist pinpoint the place it got here from and whether or not it has developed new mutations.
They’ve had international cooperation from the scientific group, all spearheaded by WHO, she mentioned, and the worldwide group engaged on the outbreak has already held three calls.
“We really have almost no experience with Andean hanta,” Blumberg mentioned.
Other infectious illness consultants like Dr. William Schaffner, at Vanderbilt University, say the state of affairs on the Hondius doesn’t have them anxious, however they’re very .
“I am transfixed,” Schaffner mentioned. “It’s an awfully uncommon circumstance the place there’s hantavirus an infection on a ship, and I’m even impressed that they’ve made this analysis.
“It’s serious, and for us, scientifically, it has all these other curiosities about location and behaviors of new hantavirus variants,” Schaffner mentioned.
“So there are lots of scientific issues, there are public health issues, there are issues of, how do you deal with seriously ill people on a cruise ship who have a communicable disease in the middle of the ocean?”