Natural Herd Immunity Strategies will not save us from COVID-19

Dr Theresa Tam, Canada’s Chief Public Health Officer

As Canadians continue to hunker down in the country-wide lockdown, Quebec’s Premier François Legault expressed interest in herd immunity this week as a means to reopen businesses and allow children to return to school. Similar calls have been made by many as a means to loosen the lockdown restrictions by achieving what is called herd immunity.

Herd immunity is a form of indirect protection from viruses where a majority of the population has been infected and recovered from a virus, thus becoming immune. Once herd immunity is achieved, it is much harder for the virus to spread, and will spread much slower, although it is not eliminated completely.

The UK initially tried this strategy, but had to change course very early on as is it became clear that hospitals would be overwhelmed very quickly and many avoidable deaths would occur. Sweden is currently using this strategy, even as its death-per-million ratio is almost 10 times higher than some of their nordic neighbours. If Canada had the same death rate as Sweden currently, we would have over 8000 Covid-19 deaths, rather than our current 2465.

This is a mistake.

undefinedConsider our home Canada, with a population of about 37.6 million. In order reach herd immunity we would need to reach about a 60% infection rate (though admittedly, the science isn’t clear here) meaning about 22.5 million would have needed to be infected and survived. Given that the estimated time for a safe and reliable vaccine to be produced is about 2 years, we we will likely not be able to reach reach herd immunity before a vaccine without overloading our healthcare system. This would lead to a massive spike in completely avoidable deaths.

Thousands of scientific studies are currently underway on different treatment methods for Covid-19. These treatment methods are either antivirals or are based on techniques to inhibit the devastating effects of the infection. These studies will be reported in the coming weeks and months and there are possibilities that we will be able to reduce mortality long before we have a vaccine. This is perhaps the most important reason for trying to push the problem ahead as far as possible. To do everything to flatten the curve. By pushing back as many serious cases into the future as possible until a treatment is approved, we will save thousands of lives.

undefinedAnother major factor mentioned by Bonnie Henry, BC’s Provincial Health Officer leading the charge against the pandemic, is that we can not 100% isolate and identify the vulnerable. While we know that the elderly and those with compromised immune systems, there are many cases of individuals who are high risk that were not aware. We do not know exactly who is vulnerable, as even young people can require serious care with people under 40 accounted for 12% of all hospitalizations.

As Henry also mentioned, in many cases it is just not possible to completely isolate many elderly people. Care homes, grocery stores, and even apartment buildings are all places where the elderly live and come into contact with other carriers of Covid-19.

There is still much to be learned about the current virus, which has spread to over 210 countries. According the World Health Organization, it is still not known whether antibodies will protect against a second infection. Antibodies are Y-shaped proteins used by the immune system to neutralize pathogens such as bacteria and viruses. The amount of time these antibodies can protect and individual is still unknown, as there is currently no evidence that people who have recovered from COVID-19 and have antibodies are completely protected from a second infection.

One final thing to consider is that we don’t know the evolution of the virus. Theresa Tam, Canada’s Chief Public Health Officer, questions that although Covid-19 doesn’t seem to evolve and mutate as quickly as other viruses, what will it look like a year from now? There is just too much at stake. As a member of the Federal Government, it is her duty to err on the side of caution.

Despite all the unknowns, Tam is encouraged that researchers from countries all around the world are collaborating and sharing findings. We all should be too. Treatments and vaccines are our only escape out of this mess.

No, Theresa Tam did not mislead the Canadian Public.

undefinedFar right, anti-science fanatics have been claiming that Theresa Tam, Canada’s Chief Public Health Officer, has been lying to the public on a few key issues surround Covid 19. Some these issues include the use of face masks, human-to-human spread of the virus, telling the public not to worry, and that notions that closing the border down would be ineffective. Reasons for these claims seem to vary, but most seem to be trying to either undermine the seriousness of the pandemic, or the leadership of the current Liberal Party of Canada. Indeed, the current Covid 19 crisis has been politicized, thanks to right wing media outlets and the buffoon who currently sits as President of our neighbours to the south.

Here we will examine these claims that Theresa Tam has either been lying or that she is incompetent, and see if they hold any water. After all, this is literally a life or death situation for millions of people across the world. Let one thing in this discussion be clear though: this is a brand new pandemic, with many unknowns factors. As scientists learn more about the virus, policies and procedures have changed to better protect populations. That is how science works.

Claim # 1 : Use of Face Masks

“Wearing masks when you’re well is not an effective measure. Sometimes it can actually present some risks, as you’re putting your fingers up and down on your face, removing your mask, putting them next to your eyes,” said Dr. Tam. This was on January 23, 2020 when the total Coronavirus cases worldwide was 845, according to Worldometer. This was the consensus world wide among virologists and epidemiologists at the time.

Issues of supply were also forecasted. It was widely known that there just weren’t enough masks available for everyone, so mask use was determined to be for those who absolutely required them such as doctor and nurses on the front lines.

undefinedIt should be noted that many countries were heavily using masks at the time. This doesn’t mean that the science was there to support such measures. Improper use of masks could actually help spread the virus, as explained earlier by Dr. Tam.

This advice was maintained until about April 6, when multiple new studies showed that virus transmission was much more common than originally thought. “Our collective scientific knowledge of COVID-19 continues to grow,” she said. “Now that more countries have had a larger number of cases … it is clear that transmission of the virus is happening more often than previously recognized from infected people right before they develop symptoms,” she said. “This is called presymptomatic transmission.”

Thus the new guidelines on homemade masks. It was then that Tam suggested homemade masks were effective at preventing the spread of Covid 19. “A non-medical mask can reduce the chance of your respiratory droplets coming into contact with others or landing on surfaces,” Dr. Tam said.

This is the current recommended procedure as of April 18, 2020. So it’s simply not true that Tam had lied or was incompetent. She was following the best available science at the time while also ensuring that Canada’s doctors and nurses would have have as much supply as possible.

Claim # 2 : Human-to-human spread of Covid 19

Is very well known now that the Chinese government tried to hide the outbreak in the initial stages, and that the World Health Organization was receiving data from them. But as of January 31, when China had its first 11,000 cases, scientists were just discovering that the virus could be spread before symptoms were shown. This is called presymptomatic spread. As early as January, Theresa Tam had been part of groups monitoring the situation and was aware of human to human spread.

Claim # 3 : Closing the borders

On February 10, the number of cases of coronavirus in China had grown to about 43,000. While this was a large number, the virus hadn’t yet been known to have made its way out of China and into other countries. Iran didn’t start feeling the hit until the end of February, and South Korea hit it’s first 1000 cases on February 26. Few, if any cases had made it Canada. This is why, on this day Dr Tam did not support travel restrictions and the closing of borders. “Of course we will be evaluating all these measures on an ongoing basis, but right now we believe that is the right balance in protecting the health of Canadians,” said Tam, while noting that Canada’s approach is in line with the World Health Organization’s guidelines related to “inappropriate restrictions to travel and trade.”

undefinedThis direction changed on March 26, as the spread of Covid 19 was well underway, Iran had almost 30,000 cases and Italy was at 80,000. The local threat was becoming more severe, as Canada and the USA were both on their initial ascendance of cases. It became a national security threat, and in order to limit the spread, border closures were deemed necessary. Once again, a timely change in directive is not the same as misleading the public.

Claim # 4 : The Public doesn’t need to worry

“It is important to take this seriously and be vigilant and be prepared, but I don’t think there’s any reason for us to panic or be overly concerned,” said Dr. Theresa Tam on January 20. At the time, she was correct. As stated earlier, the virus was only present in China, and containment within China was the main goal. As the world watched the pandemic move to other countries, such as Italy and Iran who were next to get hit, Canadian health officials, along with Dr. Tam, changed their course of action.

As early as March 6, she had changed her tune: “We’ve been having these plans, we’ve rehearsed them, we’ve been through a previous pandemic, we’ve been through co-ordination for Ebola response, for example. So each individual player in the federal and provincial system knows how those co-ordination mechanisms work.”

Far right calls for resignation

There have been calls for Theresa Tam to resign, due to so-called “misleading of the public.” As we have seen, these calls are baseless accusations. A quote from Dr. Tam is pulled from and earlier time, when much less was known about Covid 19, and applied to the current situation. We can see that Dr. Tam has been guided by the best science available, and updates her guidance as necessary.