The headline is eerily familiar.
A mysterious virus outbreak has left passengers stranded on a cruise ship and three people have died. Countries that refuse entry to their ports. Further potential infections are occurring among passengers who disembarked before knowing what other passengers were carrying.
For some, this report may feel like deja vu, reminiscent of early 2020 and the beginning of the coronavirus pandemic. However, the World Health Organization (WHO) and infectious disease experts around the world consider the threat of a broader outbreak to be very low.
“This is not a new coronavirus. This is not influenza,” Dr. Maria van Kerkhove, WHO’s head of epidemic and pandemic preparedness, told a news conference in Geneva on Thursday.
Dr. William Schaffner, an infectious disease professor at Vanderbilt University, said that unlike the new coronavirus, human-to-human transmission of hantaviruses is extremely rare and requires extremely close contact.
“I think this will be a pretty limited situation for cruise ship passengers, but it could spread a little bit beyond that,” he said. “But I don’t think we’ll have another pandemic.”
Still, he cautioned, “This is an evolving situation and what we say may change as more information comes in.”
What is hantavirus?
According to the WHO, “Hantaviruses are a group of viruses transmitted by rodents.” This strain, present in the Americas, can cause hantavirus cardiopulmonary syndrome (HCPS), a severe respiratory disease with a fatality rate of up to 50%.
The Andes strain is the only variety for which human-to-human contact has been recorded, and that is usually limited to people who have had very close contact with a sick person, such as people living in the same home.
Hantavirus is fairly rare, but the number of infections is increasing in Argentina as the temperature increases, reports the Associated Press. Since June last year, Argentina’s Ministry of Health has reported 101 cases of hantavirus, almost double the number from the same period last year.
What we know so far about the current outbreak
Eight cases of hantavirus infection have been reported among people on board the Dutch expedition ship MV. Hondius. Operated by Oceanwide Expeditions, it set sail from Ushuaia, Argentina, on April 6, before heading to Antarctica and then Africa, according to the WHO. Five of the eight infected people, including three who died, were confirmed to be infected with the Andean strain, which only lives in South America. All but one fell ill on board. The passenger disembarked before the outbreak was known and is currently hospitalized in Zurich, WHO said.
moreover, new york times Another person reported being tested for the virus. The person was a KLM flight attendant who had been on a flight with an unwell passenger in Johannesburg, and was later determined to be too unwell to fly.
How did they get on the ship?
How the hantavirus got onto the expedition ship is a question researchers are ultimately trying to answer. The couple who are believed to have first contracted the virus had been on a bird-watching tour in Argentina for several weeks before boarding the ship, where they may have come across rat feces, urine and saliva, health officials said.
David Friedman, an infectious disease professor at the University of Alabama at Birmingham, said another possibility is that a rodent may have boarded the ship and spread its fecal particles through the ship’s ventilation system. But one cruise expert says rodents on ships are rare. USA Todayand the ship’s operator, Oceanwide Expeditions, told the WHO that no rodents were found on board.
How many people are still in the MV? Hondius How long is the ship?
Oceanwide Expeditions said the ship, which had about 90 passengers on board, was denied entry to Cape Verde, an island nation off the west coast of Africa, earlier this week, although it was granted medical evacuation. The boat is heading to the Canary Islands and Spanish authorities have pledged to work with the WHO to disembark the passengers safely.
Did it spread outside the ship?
As of Thursday, no cases of infection had been reported off the ship, apart from the Zurich passengers and the cabin crew who are being tested. But on April 24, more than 20 passengers from at least 12 countries, including the United States, disembarked the ship without contact tracing and boarded flights to destinations around the world, including California, Arizona and Georgia. Health officials in those states and around the world said they were monitoring these passengers and developing information about who they came into contact with.
How long will it be before we know whether the outbreak will continue to spread or come to an end?
Because hantavirus has an incubation period of one to six weeks, infectious disease experts say there may be occasional cases of secondary infections in the coming months, including doctors treating patients and people who may have had close contact with infected ship passengers.
“I think it’s going to burn out pretty quickly,” Friedman said, noting there’s no need to panic if there are sporadic cases in the coming weeks.