The news follows a report from France that a man was infected with the coronavirus on December 27th, several days before the first cases were reported in China. The patient was diagnosed with pneumonia but a sample taken at the time has now tested positive for the coronavirus. That man has fully recovered since his illness, but reportedly has no idea how he caught the virus.
Now state epidemiologist Anders Tegnell has said there were likely infected individuals in Sweden at this time too.
“There wasn't any spread [of infection] outside Wuhan until we saw it in Europe later. But I think that you could find individual cases among Wuhan travellers who were there in November to December last year. That doesn't sound at all strange, but rather very natural,” said Tegnell.
Currently the first confirmed case of the virus in Sweden was a woman in Jönköping who tested positive on January 31st after a recent trip to China. She has since recovered from the illness.
Follow the latest updates on the coronavirus situation in Sweden (paywall-free)
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The 2019 Summer Military World Games were held in Wuhan in late October, and a troop of more than 100 people from the Swedish Armed Forces stayed in the city for two weeks during this time. Several of those who competed fell ill and were tested for the virus, although none were reported to have tested positive.
Knowing when and how the first cases in a country occurred can be helpful to understanding the spread of infection. But there are no plans in Sweden for large-scale testing of samples from patients who received care for respiratory symptoms or flu last year to see if they had the coronavirus.
“It's not something that's being discussed in a structured way,” said Tegnell. “At the moment it feels like we don't want to burden the healthcare sector with this type of investigation. They have a lot of other things to do, and this would not lead to any measure.”
He added: “Instead, what could be interesting to find out is how the virus spread in China and how it behaved in the early stages of its spread. If it was an individual spread from an animal to a person or if it spread to a group of people over a longer period of time.”
“There aren't many instances where we have been able to track a contagion of a completely new virus from animals to humans. We don't have much knowledge of how this happens in reality,” Tegnell explained. “It would be valuable to see how people could protect themselves against this type of development in the future.”