July 12, 2021
Written by: Jenna McHugh
The vaccine roll-out is well underway in Canada with almost 70% of the population having had at least one dose and second dose rates climbing steadily. Most provinces have pivoted their reopening plans from case counts and replicability (Rx), to vaccination rate percentages. Vaccination rates are indicative of a move towards herd immunity, which has been a term that has had multiple connotations since the onset of the pandemic. In early 2020, the language of herd immunity voiced by the media constituted a push towards remaining open, such as the initial response in Sweden. Herd immunity was a goal that would cost far too many lives. Now, because we have a vaccine, the push and praise for herd immunity is the mainstream discussion; herd immunity through vaccination is the desired goal. This switch has altered the narrative surrounding herd immunity, leaving behind the original notion of spreading the virus, towards a vaccinated population. Unfortunately, during this shift, the narrative promoting vaccine immunity has completely neglected the immunity associated with the previously infected.
Herd immunity occurs when a virus can no longer spread because it encounters individuals who are already immune, either through vaccination or previous infection. It is a moving target during a novel disease because there is no clear evidence in population percentages of immunity that will stop the spread of said virus. The percentage of immunity required is calculated based on the Rx of a virus. For example, in order for there to be herd immunity for the measles, 95% of the population must be vaccinated in order to protect the 5% who are not because the Rx for measles is typically between 12 and 18. The calculations of this threshold are dependent on what is happening in the community and the R value. Therefore, the herd immunity threshold in a community can continue to change based on the control of the spread. For SARS-CoV-2, the threshold can range from 10% to 70% or even more. However, most models show a herd-immunity close to 60-70%, but herd immunity thresholds can only be observed with certainty with data in retrospect.
The vaccines have, so far, been successful at reducing hospitalizations, reducing transmission of COVID and reducing the severity of disease1,2. Even with the increasing concern around the Delta variant, vaccines are proving effective. With growing vaccination rates, we are now seeing new guidelines emerge, giving those with double-doses special privileges, most notably, crossing the US-Canada border to enter the country without quarantine. This is seemingly wonderful news; an open border means less restrictions on travel and that our governments are less concerned with the spread of COVID. Finally, at first glance, it appears we are interested in trusting the science.
Unfortunately, these new guidelines are completely forgetting about the other immune population- the previously infected. The population who were infected and their bodies naturally developed antibodies are continually left out during these instructions. The previously infected have not been included in any mention of reducing quarantine or in percentage counts toward herd immunity. Study after study indicates that those who are previously infected have the antibodies required to do everything that the vaccines provide. A large cohort study of 25 661 participants concluded that a previous infection reduced the incidence of infection by at least 90%. Moreover, a (not yet peer reviewed) study identified that T cells, important antiviral effectors, persist and continuously differentiate in coordinated fashion after recuperation from a typical case of mild COVID-19. Research from the La Jolla Institute for Immunology found that the components required for long-term immune protection such as different types of T cells, antibodies, and B cells have all been found in people who recover from SARS-CoV-2 were present and had only declined modestly at 6 to 8 months after infection.
Research is now highly persuasive in its suggestion that natural immunity from COVID is just as useful as the immunity associated with the vaccines. We have multiple studies indicating that natural immunity is longstanding, sufficient and tough enough to perform all the same tasks as the vaccine. Therefore, it is imperative that those who have had COVID be included in the rates of protection towards the goal of herd immunity. Why is it that they are being left from the guidelines? Haven’t those who had to isolate away from their families, suffer symptoms and illness be offered the same privileges as those who are vaccinated if we are following the science? Why is the public health response consistently coming up short in the recommendations for populations and neglecting those who were genuinely sick, particularly when they are so focused on equity?
Given the lack of long-term evidence of the new mRNA technology, why are governments recommending the previously infected receive a vaccine? We are seeing this across Canada. If the vaccine dose is considered precious and expensive, and it’s something that should be donated to service poorer countries, why would governments recommend we waste doses on those whose immune systems have succeeded? Even more, is that ethical? Considering the lack of information surrounding the long-term risks of the vaccine, why would we poke those who won’t receive any of the vaccine benefits, while simultaneously exposing themselves to future potential risks? It’s illogical. Because this doesn’t seem to add up, it gives pause to those who are already skeptical. The idiocy begs the question of something more sinister, is this more about business and money than following scientific evidence? Or are our political leaders looking for re-election? What gives?
This is not a discussion of whether one should, or should not receive a vaccination. I am simply questioning the motivations of those who tell us to follow the science, only to turn their backs to evidence that is so clearly relevant. Particularly, when that same evidence is providing those with their vaccination status more privileges than those who were recipients of the virus.
- Leshem, E., & Lopman, B. A. (2021). Population immunity and vaccine protection against infection. The Lancet, 397(10286), 1685–1687. https://doi.org/10.1016/s0140-6736(21)00870-9
- Funke, D. (2021, June 21). Fact check: COVID-19 vaccines provide safer, more consistent immunity than infection. USA Today. https://www.usatoday.com/story/news/factcheck/2021/06/21/fact-check-vaccines-offer-safe-consistent-protection-covid-19/7609402002/.
Jenna McHugh is the Founding Editor of Vigor. Follow her at @jennoratorr