Many things are still unknown about viruses, especially the novel coronavirus (2019-nCoV) that has been spreading around the world from early this year, when it began in Wuhan, a city in central China.
For example, it’s possible that certain individuals can spread the disease to more people than others do, as is the case with so-called “super-spreaders,” someone who ends up infecting a disproportionately large number of individuals.
A UK national who contracted the novel coronavirus (2019-nCoV) at a conference in Singapore has gone on infect at least eleven others in three different countries, leading experts to surmise that this person, a middle-aged businessman from East Sussex, is an example of a “super-spreader.”
From January 20 to 22, the man attended a conference at the Grand Hyatt Hotel in Singapore that had been organised by the company where he works, Servomex. Incidentally, a Malaysian man and two South Korean men also trace their infection from their stay at the Grand Hyatt, wherein others who had come from Wuhan were also present.
On January 24, the British businessman went on a skiing trip to Mont Blanc, France, together with a group. After the businessman had gone back to the UK on January 28, five other members of the group fell ill with 2019-nCoV. They were hospitalised while still in France.
The businessman submitted himself for testing for the virus upon his return to England, after he had been informed by the organisers of the conference in Singapore that some of the attendees had gotten infected with the virus. His tests came back positive.
Meanwhile, four other people from the group had fallen ill with 2019-nCoV.
And then, another member of the group that had gone on the skiing holiday, a British man who was based in Spain, tested positive for the virus when he was already back in Mallorca.
The Guardian quotes infectious disease specialist at Cardiff University, Dr Andrew Freedman, as saying “This is not particularly surprising but it does appear that the index case has passed on the infection to an unusually large number of contacts. As such, he could be termed a super-spreader.”
At the moment, health authorities in the UK are looking for those who shared flights the man as he returned from France to England after the ski trip.
What makes a super-spreader?
What defines a “super-spreader” is dependent on the disease. For MERS CoV, infecting six individuals made someone a “super-spreader”, for SARS, it was eight.
There is also a danger in publicly labeling someone as a “super-spreader”, as this could cause to them being stigmatized. According to Dr Sylvie Briand, the director of pandemic and epidemic diseases at the World Health Organization (WHO),”We need to talk about super spreading events and not people. [It is] the circumstances and the situation that makes transmission exist, not the person itself.”
Several factors can contribute to one becoming a “super-spreader,” such as whether or not the person has travelled a lot, their hygiene, their level of contact with other people, etc.
There can also be certain biological factors at play, whether a person has a particularly high viral load can determine if they become a “super-spreader.”
Jonathan Ball, a professor of molecular virology at the University of Nottingham, said, “In most outbreaks you’ll find super spreaders but we don’t really understand the mechanism. What we often think is these people are producing lots of virus, and that generally translates to lots of transmission potential. But why do certain people produce lots of virus? We’re unsure.”
In Wuhan, ground zero for 2019-nCoV, one patient was said to have infected as many as 10 health workers.
And here’s another thing—so-called “super-spreaders” are not necessarily those who are very sick, even if they show a high viral load or are contagious for a longer period of time.
Case in point is the British businessman who had gotten infected in Singapore, who was, after all, well enough to have gone on a skiing trip after he had come from Singapore, and then gone to a pub for drinks after he had returned to England from France.
According to Professor Ball, “We often think of super spreaders as producing lots of virus, which translates to a lot of transmission potential and suggests they are showing symptoms. But it sounds like this guy was not super ill in France, so it’s going to be important moving forward to know if he had overt symptoms or not.” -/TISG
Read related: WHO launches investigation into SG conference linked to three Wuhan virus cases
WHO launches investigation into SG conference linked to three Wuhan virus cases