The coronavirus 'super spreader': How one individual infected 52 people in just hours.

On March 10, three days before the White House declared COVID-19 a national emergency, an individual attended a choir practice in Mount Vernon, Washington.

Usually, the choir group was attended by around 122 people at the Mount Vernon Presbyterian Church.

But amid growing fears around the pandemic, only 61 turned up.

Watch: Mamamia’s Claire Murphy breaks down your most asked questions about COVID-19. Post continues below.

At the time of the practice, there were no known cases of COVID-19 in the Mount Vernon area. But when the individual, now referred to as a “super spreader” attended the choir, they had developed some mild cold-like symptoms.

In a case which has now been researched by infectious disease specialists, the choir group had a 40-minute mass practice, followed by a 50-minute practice in two smaller groups. In the two groups, one group sat in a smaller room on benches, while the other group gathered in a larger room while sitting in chairs in a tight cluster.

After a 15-minute break, which included a shared snack of cookies and oranges, the two groups reconvened for another 45-minute mass practice, before the choir members headed home.

Throughout the practice, the choir members followed a few precautions, such as not hugging or shaking hands. However, they didn’t all follow further social distancing measures, such as remaining at least 1.5 metres apart. While gathered for the mass practices, for example, the choir members sat around 15-25 centimetres apart.

Within just days of the practice, a few members began showing symptoms of COVID-19.

Finally, within 12 days of the practice, 52 out of 61 attendees had contracted the disease. That’s 86.7 per cent of the attendees.

Although most of the patients, who were largely older women, did not have any underlying conditions, three members with underlying health problems were hospitalised.

Of those three patients, two later died.

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What is a super spreader?

As per The Independent, a super spreader is a patient who infects significantly more people with a disease than usual.

Since the COVID-19 pandemic began, doctors have generally maintained the number of people one person with coronavirus will infect is on average two to three people.

But because this is just an average, a small number of patients are known to infect others far more or less.

As Mark Woolhouse, a professor of infectious disease epidemiology told The Independent: “With a super spreader you are just seeing the tail end of that [average] distribution pattern.”

He also explained there isn’t a concrete explanation for the existence of super spreaders, adding: “We do not know why some people are super spreaders, the medical question is whether this is just about chance and a particularly unlucky sequence of events or there is something different about this person.”

Have there been other coronavirus super spreaders?

The Mount Vernon choir case is just one of many examples of ‘super spreader’ events that have occurred since the outbreak of COVID-19.

In South Korea in February, one woman, nicknamed Patient 31, attended services at the Shincheonji Church of Jesus after refusing to be tested for coronavirus.

At the time, South Korea had just 30 confirmed cases of the virus.

In the weeks that followed, cases in South Korea grew exponentially, with hundreds of cases linked to Patient 31.

According to Reuters, "The Korea Centers for Disease Control & Prevention (KCDC) obtained a list of 9,300 people who had attended those two Shincheonji church services, around 1,200 of whom had complained of flu-like symptoms. Hundreds of cases have now been confirmed there."

Similarly, in Albany, Georgia, the funeral of a retired janitor in February led to dozens of coronavirus infections in the small town.

In Australia in March, a wedding at Stanwell Tops on the New South Wales South Coast became national news when 37 of the couple's 120 guests tested positive to COVID-19.

Have there been cases of super spreaders in the past?

Super spreader events have been recorded for decades.

In the 1900s, one woman, Mary Mallon, infected 51 people with typhoid.

In 1998, a student at a Finland high school infected 22 other students with measles.

There were also cases of super spreaders in Singapore amid the 2002 SARS epidemic.

Feature Image: Getty.

For more on this topic:

• Conspiracy theorists said she was coronavirus patient zero. Her life became a 'nightmare'.
• How to have a conversation with someone who believes 5G is the cause of COVID-19.
• More layovers and rules for bathrooms: What airline travel is about to look like.

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