HEPA Filters, Focus on Ventilation Can Help Open Economy

This week, much of Ontario moves out of a complete lockdown (I finally get a hair cut!). The move itself has not been without controversy, with some critics saying the government is opening too fast, and others saying they’re opening too slowly.

There is no doubt in my mind that if we can re-open the economy safely, we should. COVID19 has done terrible damage over the past year. Lives lost. Families unable to say goodbye to their loved ones. On going health issues in those who survived COVID19 infections and much, much more. But there is also an increase in the number of people suffering from mental illness, a rise in domestic abuse, and very real economic hardships faced by millions of Canadians.

It has been noted that there were were more deaths than expected in Canada last year, and not all of these “excess deaths” were directly caused by COVID19. We are starting to realize that some of deaths are “indirect”. That’s to say, the social isolation, the lack of emotional, financial and other support, the delayed medical procedures and more, have caused these deaths.

This situation is particularly bad in British Columbia and Alberta, where there were 270 and 360 more deaths than expected between March 15 and April 25 alone, and these were not directly attributed to COVID19.

To be clear, the lockdowns were necessary. And if we open the economy in an un-safe manner, COVID cases will rise again, there will be more death and perhaps even a dreaded third wave. We’ve seen from Sweden what happens when a country doesn’t shut down in the face of COVID. Even their king has admitted Sweden’s approach was a total failure.

It’s just that we cannot ignore the pain and suffering that occurs by a lockdown as well.

That’s why to my mind the focus needs to be on how to re-open safely. We have one of the worst pandemic responses in the world, so we must do better. Is there something we can do, that hasn’t been done in Canada yet?

Turns out, there just might be.

For far too long, Health Canada did not focus on airborne spread of COVID19. They stressed the “droplet” method of transmission, where fluid particles are expelled from your mouth, land on a surface and are then when you touch them, wind up on your fingers, and then into your body when you touch your eyes, nose or mouth. Full disclosure, if you search hard enough, you can find a video of me somewhere on the net saying exactly that, and telling people not to wear masks. It is clearly outdated now, and should be ignored.

Japan, by contrast, focused on airborne spread as far back as February of 2020. Their whole focus was to ensure proper ventilation and using air purifiers with HEPA (High Efficiency Particulate Air) filters in rooms. Everybody was asked to wear a mask early last year. Granted it is culturally more accepted to wear masks in Japan. But the focus was on airborne spread right from the start.

A diagram showing Japan’s process for dealing with COVID19, part of their submission to “Environment International” – September 2020 edition

How well did Japan do? Japan has a population of 125 million people in a country about 3/4 the size of Baffin Island. As I write this, data from their COVID tracking system shows that 417,116 people have been infected (0.33% of the population) and 7,038 have died (.0056% of the population).

These numbers are all the more remarkable considering that Japan did just about everything else wrong. They did not test enough (at least at the beginning), the lockdown measures were half hearted and voluntary, many pachinko parlours (a mix of gambling and alcohol) stayed open, and traffic on their notoriously crowded commuter trains to work was only down 18%.

Health Canada did not even acknowledge airborne spread of COVID19 until November 2020 (9 months after Japan and 4 months after the World Health Organization). Our Covid19 tracker shows terrible results. We have a population of 38 million. Yet as I write this, we have had 826,528 cases (2.17 % of the population or 6.6 x as many as Japan on a pro-rated basis) and 21,309 deaths (.056% of the population or almost exactly 10 x as many deaths as Japan on a pro-rated basis).

It does make one wonder, if we had approached COVID19 as having airborne spread right from the start, could we have saved a number of lives, and limited the lockdowns we endured? And now that the evidence is strong that COVID19 is airborne, should we not have businesses focus on safe ventilation as a condition for opening?

What’s required for optimal ventilation? Well ideally, you should have an HVAC system that exchanges the air in a given room 6 times an hour with an HEPA filter. HEPA filters can remove the vast majority of droplets that the COVID19 virus (and other viruses!) live in. But the reality is that this would be ultra costly and take far too long to replace every HVAC in most commercial buildings. (Should definitely be a requirement for new commercial properties and especially the new nursing homes Ontario is building).


What can other businesses do instead? One of my patients is a manager at a Tim Hortons. They have 14 tables at the Tim’s. What if the restaurant put a portable air purifier with a HEPA filter on each table? There are many brands that cost $80-$100 each for a small size one. But with one on each table (where people would be talking and eating without masks, thus expelling the virus), you could reduce viral spread.

Granted at that price, the air purifiers would only last about six months, but by that time hopefully we will all be vaccinated anyway.

Similarly, we could mandate appropriate air purifiers in other businesses as requirement for opening. To be clear, people should still wear masks, wash hands regularly and physically distance as much as possible. Those are important and necessary precautions for re-opening. But the HEPA filter purifiers would simply provide that extra level of protection. It’s why I asked my nursing home to install them in their facility (and thank you to the owners of Bay Haven for doing that).

Canadians have suffered terribly over the past year. For the sake of our physical and mental health we need to re-open the economy, but do it in away that will not increase COVID19 infections, and not have us yo-yo between lockdowns and re-opening. Focusing on ventilation and HEPA filters can help us do this safely.

Get Your Flu Shot…..in NOVEMBER

Every year in my office, usually just after Labour Day, the influx of phone calls begins. It’s always the same question -“When are you giving the flu shots?” While it’s easy to grumble about the increase in calls, the reality is that patients who are calling are being pro-active about their health. This is to be lauded as pro-active patients often have the best health outcomes.

Above image from St. Patricks Home of Ottawa.

This year the phone calls came earlier than ever. There’s a general sense in my practice that more people want the flu shot (a good thing) as patients are concerned about winding up in hospital, and contracting COVID19 while there. The fear of a “double threat” in hospitals is high, and I suspect that more people will get a flu shot this year because of this same fear.

This is also compounded by some erroneous information out there about what the flu is. A lot of people who have a cough, or the sniffles or a low grade fever think they have “a touch of the flu.” That’s not really the case. If you have a cold, you will have a fever, cough, and runny nose, but you will not feel like you’re on death’s doorstep.

If you have the flu, in addition to those three symptoms, you will feel like you got run over by a truck twice. The second time because the flu virus will have wanted to to ensure you really really felt it’s presence. Muscles you never knew existed will hurt for days, and it will be an experience you won’t soon forget.

So a lot of people who are getting a cold are concerned that the flu season is already starting. It’s not.

According to Canada Flu Watch, as of October 4, there is an exceptionally low level of flu activity across Canada. The percentage of positive flu tests is a mere .05%, which is well below normal. The flu is not in Canada (yet). I think most physicians would agree that an emphasis on social distancing, hand washing and mask wearing has had a large roll to play in this. Those three things don’t just reduce the spread of COVID19, they also reduce the spread of other viruses, including the flu.

Usually flu season begins around the first week of November with a few cases, peaks in January, is of concern until the end of March, and occasionally drags on into May (see below).

Graph is from the excellent Ottawa Public Health website

However, since the flu numbers are so low this year, it is likely that our flu season will be delayed somewhat. It appears that we can wait just a little bit longer to get it this year (but you should get it)!

The trick with getting the flu shot is timing. It takes your body about two weeks to build up full immunity after getting the flu shot. But, after about 28 days, the immunity starts to wane, slowly perhaps, but it does wane. (Medical nerds out there may want to read this study). Getting the flu shot too soon, means it may wear off before the season ends.

This year, what would be the best thing to do?

First, just about everybody over the age of six months should get a flu shot to protect themselves and their loved ones. The number of people who truly, truly have adverse reactions to the flu shot is very low. Talk to your doctor if you have concerns.

Second, for people who are in nursing homes and retirement homes, it probably is worthwhile getting the shot the last week of October. These patients are truly truly high risk, and it may take them longer to develop immunity.

Third, for most other people in the community, the first couple or three weeks of November are likely the ideal time to get the flu shot this year. My own office won’t even be having our flu shot clinics until November (my patients will get emailed once we firm up the logistics). This is being done to ensure that we all have a reasonable amount of immunity until the end of the flu season.

So let’s all do our part. Continue to social distance, wear a mask, wash your hands frequently (for 20 seconds) and get a flu shot in November. Together, we can ensure that the the double threat remains a threat, and not a reality.

Disclaimer: The opinion above is not individualized medical advice. It’s meant for the population as a whole. If you have specific questions or concerns, speak to your doctor.