This article was originally published in the Montreal Gazette
With the start of the academic year upon us, many people have been asking how we can protect students and prevent outbreaks in schools. The good news is that the situation today is much better than it was a year ago because the vaccine rollout has drastically reduced the number of daily infections. So even though we are now at the beginning of a fourth wave, we should remember that without the vaccines the numbers would be much higher than they actually are.
Still, how to handle the return to school is an evolving issue even though many of the solutions remain largely the same. Wearing masks, physical distancing, ensuring proper ventilation in classrooms are key. But the most important thing we can do to protect students is to get vaccinated.
Obviously, a classroom full of vaccinated students is going to be a much lower risk setting than a classroom with only some or no vaccinated students. Especially as in-class learning resumes, ensuring high vaccination numbers is going to be key in preventing viral transmission in schools.
But many are worried about the under-12 crowd that cannot receive vaccinations yet. While data on this age group is expected later this year, for now students under 12 need other protections against the virus. That protection is us.
Throughout this pandemic, many people have been talking about “herd immunity,” although not always using the term correctly. Basically, herd immunity means that if enough of us get vaccinated, we can protect others in the population who cannot. Much like a herd of animals will protect their young by surrounding them and keeping them in the centre of the herd, so too we can protect our young by getting vaccinated and metaphorically surrounding them by a wall of people immune to the virus.
The reason such strategies work is that most viral transmission occurs at home. While workplace outbreaks have happened and are an issue in and of themselves, household transmission was and is a major driver of the pandemic. The reality is that you spend more time with the people you live with than with most others in your life. As any parent with young children knows, when a viral illness infects one member of the family, it will quickly infect everyone else in the house. A recent updated systematic review found that the secondary attack rate — in other words, the risk of the virus infecting another member of the same household once one person was infected — was almost 20 per cent overall. However, when researchers looked at studies done between July 2020 and March 2021, during the worst of the second and third waves, the secondary attack rate was over 30 per cent. There was also some evidence that the secondary attack rate went up as more infectious variants emerged.
The worry, of course, is that students could catch COVID-19 at home and then come to school and infect their classmates. There always has to be a first index case in any school outbreak and statistically that index case is most likely to catch the virus from their family. And so the best way to protect younger students who cannot be vaccinated is to get vaccinated ourselves. The less COVID-19 there is circulating out there in the community, the less likely it is to enter your home and the less likely that it will be brought into our schools.
The goal of vaccines is not just to protect ourselves, but also to protect the most vulnerable in our society like our children. Dismissing vaccinations because you think, rightly or wrongly, that you are at low risk for complications from COVID-19 misses a key point. We get vaccinated not just to protect ourselves, but the other members of our herd as well. There’s an important lesson in that. To avoid danger animals form herds and stick together. Only humans try to save themselves.