Blenheim church outbreak an example of a 'quintessential super spreader event'

A COVID-19 community outbreak at a church in the town of Blenheim that has led to 31 active cases and put an estimated 300 people in isolation is the "quintessential super spreader type event," according to a Toronto epidemiologist.

The Word of Life Church in Blenheim decided to temporarily close its doors on Oct. 22 for two weeks as a family from its parish contracted COVID-19. At the time, the pastor said he was closing the facility out of precaution and because he had been told by the health unit to self-isolate.

A week later, Chatham-Kent Public Health says the incident is responsible for dozens of cases and has led hundreds more to self-isolate.

Infectious disease epidemiologist from Toronto Ashleigh Tuite told CBC News that it's likely cases will rise in the coming weeks as a result.

"It's really the convergence of closed spaces, so indoor spaces, spaces where people are crowded together and when there's a lot of close contact happening," Tuite said.

"So, you know, in the situation of some previous events that are like this, one of the things that's been noticed is that there's lots of singing happening ... the virus spreads more readily when people are talking loudly or singing."

Places of worship might have higher transmission risk

Small spaces, the amount of time people spend in an area and how people are communicating results in an increased transmission risk as compared to a store, Tuite told CBC News.

While the exact cause of transmission is unknown, Tuite said even if people were wearing masks they aren't completely effective, especially if people are loudly talking or singing.

"You're spending a fair amount of time, people are singing, as much as people are trying to avoid physical contact and keep distance ... I think part of the nature of those sorts of communities is that people are spending time close together," she said. "Unfortunately, at this point [there] have been a fair number of sort of larger outbreaks happening and in places of worship."

Chatham-Kent medical officer of health Dr. David says he's been told that members of the church wore masks all the time.

But he has expressed concerns over a photo seen online showing two members not wearing their masks.

The circumstances of the photo are not known. It's not clear from the photo how many people were in the room, or how long the masks were off or whether or not this was a one time thing.

The photo was taken nine days before the church closed its doors after people became sick with COVID-19.

Colby says he has raised the photo with the church but public health is not taking any action.

Closed for now

While the church has closed its doors for now, Tuite said they really need to make sure they understand how the virus spread before returning.

"If it's an issue of ventilation, even coming back in two weeks, if people are physically distancing, if they're wearing masks, we might expect this to happen again. So I think it's really important to learn from this event," she said.

"It's really a combination of wearing masks, having physical distance and also making sure that you have good ventilation."

But Colby was a bit more on the fence of whether the virus is more prone to spread in a church.

"All cases of the virus ... represent a breakdown in some type of infection control. If we're all paying attention to hand hygiene and physically distancing from one another then we're not going to see secondary cases," he said, adding masks and a limited capacity play a role too.

"We're still investigating as to why the attack rate was so high in this church, we've been told that they complied with these instructions."

Some allow temporary removal of masks in worship spaces

In Windsor-Essex, the health unit's website states that the temporary removal of one's mask while "conducting or participating in religious ceremonies" is allowed.

Meanwhile, Chatham-Kent's municipal website states that masks are required during all indoor religious services and "there is no exemption in the by-law for the congregation to remove their masks during worship."

But under the same municipal guidelines, someone does not have to show proof of a medical condition if they can't wear a mask in an enclosed public space.

As of Friday, Chatham-Kent is reporting 35 active cases and three people in hospital. In total, 450 people in the region are self-isolating.