A "circuit-breaker" that took effect in New Brunswick Friday evening could help reduce transmission of COVID-19, but infectious disease experts say those results won't become apparent for at least a week or more.
As of 6 p.m., residents living in parts of Zone 1, 2, 3 and 5, and all of Zone 4 are required for the next two weeks to limit private indoor and outdoor gatherings to include only members of their household, in an effort to curb high rates of COVID-19 transmission and reduce hospital admissions.
Premier Blaine Higgs referred to the measure as a "circuit-breaker" when he announced it at a news conference on Tuesday, saying evidence points to transmission occurring during private gatherings.
Residents in the circuit-breaker zones will continue to be able to attend school and go to places of recreation and leisure such as restaurants and gyms, which for the last two weeks have required proof of vaccination.
A circuit-breaker, unlike a lockdown, is typically a public health measure implemented for a fixed amount of time with the goal of reducing community transmission of a disease, while minimizing potential harms caused by restricting people's freedoms, said Dr. Matthew Oughton, an attending physician in the division of infectious diseases at the Jewish General Hospital in Montreal.
The term has been used before COVID-19, but since the pandemic began, jurisdictions around the world have employed circuit-breakers in a bid to slow transmission of the disease, Oughton said.
Oughton said New Brunswick's circuit-breaker should help to reduce the transmission of COVID-19 by temporarily reducing interaction among people, particularly those who aren't vaccinated.
But given the disease's incubation period of one to 14 days, evidence that the circuit-breaker is having any effect on case counts likely won't come until after the two weeks are over, he said.
"For that two-week time that you are enacting these measures, it's very reasonable to expect to see no immediate effect," Oughton said.
"In fact, that's almost predictable that you won't start to see any reduction in cases, which means during those two weeks, you might even see further increases, which often can lead people to say, 'Well, look, we're doing all these things now for a week, and it's not working'."
Dr. Brian Conway, medical director of the Vancouver Infectious Disease Centre, said he thinks the impact of the circuit-breaker could become noticeable about a week after it began.
"Until a week from today, we won't necessarily know if the circuit breaker's having an impact," Conway said. "It is at that point that we will begin to see the decrease in the number of cases."
Proper communication, enforcement necessary: expert
As results of the circuit-breaker aren't expected to be immediate, Oughton said it's important that provincial officials communicate clearly to maintain the public's participation.
"That has to be, I think, very clearly explained in multiple different ways to the population that is affected, so that people understand what to expect and what not to expect," Oughton said.
Enforcement will also have to play a role in the province's strategy if it wants to see results from the circuit-breaker, Oughton said.
"You have to have some plan for monitoring and enforcement, I think, if you want to have this be as effective as possible."
Should there be a benchmark for issuing a circuit-breaker?
The number of available hospital beds — particularly ICU beds — is one of the most important indicators of how well-equipped the health-care system is to deal with COVID-19 cases, Conway said.
"So if that capacity is threatened... then that requires the system to really shut down very significantly to preserve that, that capacity," Conway said.
As of Friday, New Brunswick had 58 people in hospital due to COVID-19, with 30 of those in an ICU.
And Horizon Health Network announced that as of next Wednesday, it would move its health-care centres to the "red alert" COVID-19 level to redeploy staff to maintain its emergency services and ICUs.
According to Conway, Alberta offers an example of how the pandemic can push a health-care system to its limits, and serves as a "cautionary tale" of what can happen.
The fourth wave of the pandemic saw hospital admissions soar in that province, prompting the Canadian Armed Forces to send eight critical care nurses to work in ICUs in the province.
"That's a cautionary tale to the rest of us to just do everything we can to not get there and to intervene sooner, which is what is happening right now in New Brunswick," Conway said.