15th April 2020
If B.C. continues to flatten the curve, and we continue to see a reduction in new cases, and increase in closed cases. When might B.C. begin to return to work? What precautions should organizations have in place for a return to work?
I have been tracking the increases in cumulative cases in B.C. Below shows new cases per week, and the cumulative total from the prior week.
It looks like we could be recovering from the initial exponential growth and flattening the curve. The last week showed only an 18% increase in new cases compared to the cumulative cases the week prior.
|Week||New Cases||Fatality||Cumulative Cases||Case Increase|
|1st Week Feb 3rd||1||1||0%|
|2nd Week Feb 10th||3||4||300%|
|3rd Week Feb 17th||1||5||25%|
|4th Week Feb 24th||2||7||40%|
|5th Week Mar 2nd||1||8||14%|
|6th Week Mar 9th||24||1||32||300%|
|7th Week Mar 16th||71||3||103||222%|
|8th Week Mar 23rd||369||10||472||358%|
|9th Week Mar 30th||498||5||970||106%|
|10th Week Apr 6th||296||20||1266||31%|
|11th Week Apr 13th||224||26||1490||18%|
Charted in the “Weekly BC COVID-19 Cases” graph below, the cumulative cases curve isn’t quite flattened yet, but the exponential increases week on week certainly are, they’re actually decreasing.
In the 8th week since the first case of COVID-19 in B.C. the province jumped from 103 cases the week before to 472 cases, which was a significant increase (358%). I had wondered what that could mean by our 3rd month, or 12th week of ongoing cases.
As a result I calculated the final weeks at various percentage increases, as outlined below.
Each percentage increase is an estimate of what week 12 would look like with increases remaining at the same levels for the final weeks (Increase of 400%, 200% 100% etc. for each week until the 12th week).
|% Increase||By Week 12||Projected BC Cases||Mild or Asymptomatic||Severe Infection||Critical Infections Requiring Ventilation||2% of Cases Result in Death|
Initial forecasts showed some dire numbers if we continued to increase in the 400% range for each of the final weeks.
B.C has actually very quickly lowered our percentage of new cases each week which has had a significant impact on the cumulative increase in new cases.
While I’ve left the high growth rates (100% to 400%) in place for the last week, with B.C’s current restrictions, and measures in place we should see another week of reductions in percentages of new cases.
Below are the final estimates based on the last few weeks of where we could end up on the 12th week.
|% Increase||Projected BC Cases||Mild or Asymptomatic||Severe Infection||Critical Infections Requiring Ventilation||2% of Cases Result in Death|
Incredibly BC has really seen a dramatic decrease in cases since that initial spike in the 8th week. I believe a 400% increase to 7,450 is incredibly unlikely.
I would hazard a guess based on the previous two weeks by the 12th week, we may end up between the 13% and 30% increase range in the table above. Perhaps around 1800 cumulative cases by week 12.
1800 cases would be incredibly low compared to what the numbers could have been with ongoing increases (roughly 26,000 cases with 200% increases) as opposed to the decreases we’ve seen.
It has to be noted, that Easter could set us back significantly and towards the end of April we may see another exponential increase week to week, however current measures should help restrict another burst of cases from Easter keeping the percentage of growth to the cumulative cases relatively low.
So what happens if we are around 1,800 cases by week 12, 3 months into this dramatic change in our province and country?
Provincial Health Officer for B.C. Bonnie Henry noted that we’re making progress, however she is reluctant to lift any restrictions for at least a few more weeks, but may consider relaxing restrictions in areas where new cases are not prevalent.
Premier John Horgan has however extended the provincial state of emergency for another 2 weeks indicating we’re certainly not ready to bounce back just yet.
How the numbers look over the next couple of weeks after the Easter weekend will be key to how Henry and Horgan respond.
There has been a lot of speculation about when B.C. might officially “flatten the curve”, and optimistically it’s possible that may be happening now.
Pessimistically it’s possible that excessive socializing and travel over the Easter long weekend could have renewed the spread of the virus amongst the population and cause a curve rebound sending us back towards exponential growth of new cases.
Eight weeks could have been the peak of the exponential growth in cases and increases, if so we may continually decrease over the next few weeks. If we decreased until the 16th week of the outbreak in B.C, that would take us to May 18th. Roughly 16 weeks since the first case in B.C.
A nice symmetrical curve.
Could that be the beginning of the end of the restrictions? Return to work, return to some degree of socializing?
Whether it’s June, July or August, organizations will need to consider how to return to work. This might include a number of considerations to minimize health risks to workers and the public. WorkSafe BC have some guidance for a number of industries. Some considerations:
Regardless of when the slow return to economic and human health starts to take place, there’s a reasonable chance a vaccine will not be available as it may take one to two years to develop.
There are (as of this publishing) 12 clinical trials authorized in Canada for supportive care or treatment of COVID-19.
So we will need to live, and work with restrictions, and the continual threat of further outbreaks hampering our health and economy.
The longer we remain locked down, the better we can reduce the existence of the virus in B.C. and with good controls the less we need to worry about another outbreak.
Henry has indicated that she may consider lifting restrictions in a few weeks, if that’s the case organizations need to make safe, prudent, and cautious decisions on how and when to start adjusting from no work, or limited work and consider how they will manage the health of our workplaces.
I’d be willing to cautiously start returning to my work with a healthy dose of precautions over the summer if B.C.’s COVID-19 statistics, health experts, and government agree.
If they don’t, I need to return to work by Christmas….not sure my little company can hold out much longer than that.
Contact firstname.lastname@example.org if you’re interested in discussing how your organization is managing safety during the current COVID-19 outbreak.
Posted in: Safety Blog