In 2018, a 68-year-old Argentinian man became infected with the Andes strain, likely while coming into contact with rodent urine, droppings or saliva near his home.
This is normally how humans catch hantavirus – Andes being the only strain known to spread between humans.
On November 3, 2018, the man attended a birthday party for 90 minutes along with around 100 other people in a village in Argentina’s Chubut Province, near the Chilean border.
Five people who had contact with him developed symptoms in the following weeks, according to the 2020 study in the New England Journal of Medicine.
Three symptomatic people – dubbed ‘super-spreaders’ – accounted for two-thirds of infections.
One man infected six other people and died 16 days after displaying symptoms.
His wife, the third super-spreader, was feeling ill when she attended his wake, where 10 more people were infected.
Scientists analysed samples from the Epuyen outbreak, and reconstructed how people interacted at the fateful party.
They found that isolation measures helped stave off a wider outbreak – and that most human-to-human transmissions occurred on the first day the infected person had a fever.
Exactly when hantavirus symptoms first emerged was ‘critical’, the study emphasised.
In more than half of the cases, transmission ‘could be accurately established as the day of onset of fever in the primary case’, it explained.
Olivier Blond, analyst and biologist at Argentine research agency Conicet, highlighted the successful containment of the Epuyen outbreak.
‘This temporary “deprivation” of freedom helped preserve the health and well-being of the entire region by preventing the virus from spreading,’ Blond told AFP.
Since hantavirus is ‘highly lethal’, he said, ‘deaths start appearing quickly, isolation measures are put in place quickly, and the chain of transmission is rapidly stopped’.
With Covid, ‘only later do deaths start to accumulate’, he said, while with hantavirus, ‘everything happens much faster.
‘That is why there is not as much chance of a hantavirus pandemic.’
