Saturday, July 18, 2020

BC COVID-19 Update, July 18, 2020

The management of the pandemic in BC has been very successful, thanks to everyone's hard work and sacrifice over the past months.

Some of us, such as emergency room or ICU staff, ambulance workers, and staff at grocery stores, have had to take on much more risk than the rest.  We need to show gratitude for this hard work:  the 7:00 PM celebration every day is a small symbol of this.

However, since the restrictions have loosened, we have predictably had an increase in cases again over the past few weeks.

I think there is a significant risk that the cases could escalate again quickly.  Then we would be in the same predicament as in March and April, although I think we would be better prepared.

Here is what we can do right now to prevent cases from continuing to surge, and to maintain our hard-won gains against the pandemic:  

1) People need to wear masks whenever they are indoors around strangers.   This includes in grocery stores, shopping malls, and on public transit.   All staff in grocery stores should be wearing masks.

Masks do not eliminate the risk of contagion, but they very clearly reduce it enough to make a big difference.  Mask use has not been emphasized strongly enough by public health authorities.

I think that we should give free high-quality masks to everyone in the population.  These should be made available at the entrance to every business, and at transit stations.  A home-made mask is fine--anything is better than nothing.  A good medical-quality mask is better, and an N95 is best of all.  Masks are available for sale at retail outlets such as Canadian Tire.

The evidence that has accumulated over the past months has shown a much lower risk of contagion outside, including in groups.  So I am much less worried about the need for a mask mandate outdoors, although I continue to think that the more mask use the better, when around other people.  I do think that there should be a mask mandate for grocery stores, shopping malls, public transit, and other indoor spaces in which strangers could meet each other.  

2) Maintain social distancing, also known as "physical distancing."  The farther you are from an infected person, the smaller the risk of contagion.  During the whole pandemic we have recommended 2 metres, or 6 feet, of distance between people.  I recommend this as a bare minimum.  The more distance, the better.  Social distancing is absolutely crucial if you are in an indoor environment.

3) Grocery stores and other businesses should continue to limit the number of people allowed inside at one time.

4) I think that if you are going to a restaurant, you should take out.  Sitting inside at a restaurant is a needless high risk activity.  The thought of opening bars seems like madness to me.

The evidence in the past months has also showed that the main route of contagion is through respiratory droplets.  There may be a small degree of true "airborne" transmission, but most spread is through close contact indoors with an infected person.  Many such infected persons do not have any symptoms, so there would be no way to know you are in contact with someone who has the infection.

The risk of such spread is greatly increased when people are talking, shouting, or singing, and the probability of contagion of course increases with the duration of time spent in a high-risk environment.     So a restaurant meal indoors around strangers, all of whom talking and laughing without masks, is very high risk.  The ventilation system in such an enclosed space can cause contagion in people downstream with respect to the air flow.

5) We are enjoying more social contact with friends and relatives, but we should continue to maintain a limited social "bubble."  Now is not a time to be inviting new friends to your home, or having dinner parties.  If you want a social dinner, consider having a picnic or a barbecue outside.

6) Hand-washing practices and cleaning surfaces such as doorknobs or shopping carts, are still recommended, but my reading of existing evidence is that contagion from surfaces (so-called "fomite transmission") is not likely.  The main mechanism of spread is through respiratory droplets in the air, spread by coughing, sneezing, talking, or simply exhaling.  Therefore, we should maintain good hand-washing practices but we do not need to be as worried about this, and we do not need to frantically increase efforts to sanitize surfaces.  Our efforts should be spent primarily on reducing contact with strangers, reducing contact with crowded indoor spaces, increasing mask use, and maintaining social distancing.

7) Working from home should be encouraged whenever possible.  An office workplace, with people in close proximity without masks, is very high-risk in my opinion.  Government support should continue to allow working from home, and financial support for people who need to take a leave from work.

8) I do not support any plan of students returning to attend classes indoors.  If there could be group activities planned for outdoor learning, in conjunction with video lessons from home, this might be a reasonably safe balance.

9) On a community level, the more we can increase testing and tracing, the better we will be able to control, or even end, the pandemic.   We can learn from other places that are controlling the pandemic very well, such as South Korea and Germany.   For example, if a home-test kit was available, manufactured with massive government-supported investment, freely provided, and if every person in the population could test themselves weekly, we could rapidly isolate almost every COVID-19 carrier, and the pandemic would be over within a month or two.  Such mass-scale testing is far from being available, but this thought experiment demonstrates how incredibly important it is to test as much as possible, including random people in the population, and people without symptoms; from there it is essential to have a system to isolate every person with a positive test as quickly as possible, as well to inform and temporarily isolate any known contacts.  This system takes leadership, organization, a vast investment of money, commitment, and hard work to set up and run. 

10) Follow reliable sources for information.  In BC, we are fortunate to have Dr. Bonnie Henry, who has been a great leader through this emergency.   There are good people to follow on Twitter for COVID-related information:  for BC news, there is @BCGovNews.  I recommend Eric Topol (@EricTopol), Max Roser (@MaxCRoser), Nicholas Christakis (@NAChristakis), the Canadian ID physician Isaac Bogoch (@BogochIsaac), David Boulware (@boulware_dr), @AndyBiotech, and for some more sophisticated virology, Professor Akiko Iwasaki (@VirusesImmunity).  There are many others, but I think these are a good start.