Ontario health experts: Vaccines key to reducing transmission, limiting spread of variants

Ontario’s Science Advisory Table has provided yet another round of modelling and say progress has stalled, pointing to more mobility as a driving force behind an increase in COVID-19 cases as variants continue to spread across the province.

The group says that while the drive to vaccinate residents and workers in long-term care has paid off in declining deaths and illness, progress against the virus has stalled outside that sector.

The key to controlling this, Dr. Adalsteinn Brown says, is ramping up vaccination efforts and focusing on regions hardest-hit by the virus and its strains.

“Our ability to control the rate of spread will determine whether we return to normal or face a third wave of infection,” said Brown on Thursday.

“We know what works: Continued masking and distancing are essential to controlling variants of concern.”

The data shows that declines in community cases and test positivity have levelled off and cases are increasing in most Public Health Units with average weekly cases soaring in regions where variants are most prevalent, such as Thunder Bay, Northwestern, and Toronto.

Over the past two weeks, Ontario has seen cases grow by an average of 1.19 percent per day.

The data suggest that the Ford government’s decision to loosen public health restrictions in late February, coupled with the spread of the B.1.1.7 variant first discovered in the UK, is to blame for an end in improved numbers.

Optimism does lie, however, in the province’s ability to vaccinate the population at a respectable and effective pace, Brown says.

 

Effectiveness against infections with no or minimal COVID-19 symptoms:

 

• 3 weeks after the first dose: 52%
• 1 week after the second dose: 90%

 

The province’s latest slides show that vaccinations are in fact on the upswing; particularly when it comes to the first of two doses required for Pfizer, Moderna, and AstraZeneca vaccines. Doses for Johnson & Johnson, the fourth treatment approved for use in Canada, has yet to be secured by Ontario.

Similar to past sequences of recent provincial modelling, Brown says a further increase in daily cases comes down to how rapidly variants spread in Ontario.

If the transmission is high, in a worst-case scenario, the province could see 8,000 daily COVID-19 cases by April 2.

A medium spread would see daily cases in the 6,000 range, with roughly 2,000 new cases reported per day in a best-case scenario.

Updated data from Ontario’s COVID-19 Science Advisory Table shows that the effective reproduction number (the number of new cases caused per one person with the virus) is at 1.24 for the new variants, while the original has dropped to 0.9.

Brown says an increase in mobility has also led to a spike in new infections throughout the province.

Recent cellphone data shows the gradual reopening of the province is doing just that with numbers suggesting more people are on the move.

Blue Mountain alone, which currently sits in the ‘Green-Zone’, saw more than 10,000 Toronto visitors in the first week of reopening. Other regions with eased restrictions, such as Prince Edward County, have also seen an influx of visitors from the ‘Grey-Zones.’

A stay-at-home order was lifted in Toronto and Peel Region in early March, moving both regions into ‘Grey-Lockdown’ in the provincial pandemic response framework.

In mid-February, Brown said that while public health and safety measures are effective and working, the highly transmissible B.1.1.7 variant remains Ontario’s biggest obstacle in curbing the spread of the virus.

The latest numbers Thursday confirm 35 additional cases of the B.1.1.7 variant first detected in the UK and 11 additional cases of the P.1 variant first detected in Brazil.

On a more positive note, the modelling shows transmission has drastically flattened in long-term care homes as residents are vaccinated. No deaths have been reported in five days as a result, Brown says.

“Controlling cases, increasing vaccinations where they will have the greatest impact, and accelerating vaccinations overall are how we beat the pandemic.”

In their most recent updated vaccination timeline, the province confirmed a significant portion of long-term care residents are immunized against the virus as the government provided details on who can expect a vaccine as part of Phase 2.

“Focused LTC vaccination, together with lockdowns, have rapidly reduced infections and deaths in long-term care”  the science advisory table concluded.

The plan will see shots administered based on risk factors including age, neighbourhood, existing health conditions, and inability to work from home.

The province says anyone above the age of 60 in COVID-19 hotspots will be able to be treated against COVID-19 by May into early June.

Ontario reported 1,092 new cases of COVID-19 on Thursday and 10 more deaths linked to the virus.