- Your mask protects others but not you
- Herd immunity can be achieved through natural infection
- The second wave will be worse than the first
- The pandemic may last for years
I have avoided writing about COVID-19, as there’s plenty of information out there, both good and bad. But I persistently hear a few misconceptions even from my well-informed, concerned friends and family. So I thought I’d address four of the most common here.
Your mask protects others but not you
I learned a lot about masks when I broke a story in the Canadian Medical Association Journal in 2009, during the H1N1 influenza epidemic. At that time, the Public Health Agency of Canada was recommending handwashing, but not masks, to protect citizens against the virus — a position that flew in the face of expert advice to wear masks.
During the current pandemic, well-meaning public health messages have stressed that wearing a mask protects the people you interact with. Here’s a typical one from the Public Health Agency of Canada:
- DO wear a non-medical mask or face covering to protect others.
People are inferring from this that masks don’t protect the wearer. Not so! Masks aren’t a one-way filter. If you wear a mask, it is definitely protecting you too. Why aren’t public health authorities mentioning this? After all, a major slice of humanity cares more about themselves than others. I notice that public health agencies often simplify messages in a way that leaves out important information. Maybe they are worried that people will think a mask is a 100% guarantee that you won’t get infected.
For the record, there are no guarantees. But wearing a mask cuts the risk to the wearer as well as people around them.
Because it’s not foolproof, don’t rely on a mask alone to protect yourself. Keep distancing, hand sanitizing, and socializing outdoors, even when wearing a mask. And add a mask to these other practices. For a mask to work, you have to wear it.
Also, make sure the mask is tight-fitting. I wear an N95 mask (available at hardware stores, look for NIOSH N95 printed on each mask) because it keeps out even small particles, lasts a long time and is secured tightly to the face with straps around the head, not the ears. A medical or N95 mask can be pinched over the nose. If you’re wearing a non-medical mask, don’t let your mask fall below your nose. Don’t pull it down on your chin – any virus particles on the outside of the mask can fly up into your mouth or nose. When you take off your mask, remove it completely using the straps and immediately wash your hands.
Herd immunity can be achieved through natural infection
When I started hearing this from sources in the U.S. and Sweden, I was mystified. From my experience working on medical journals, I knew that “herd immunity” was usually discussed in the context of vaccination. The question is, what percentage of the population do you need to immunize to stop spread of a disease? For a highly contagious disease like measles, it has to be pretty high, around 85%.
COVID-19 is fairly contagious, although not as contagious as measles, so rates of combined immunization and infection to achieve herd immunity have been estimated at 50% to 60%. In reality, we won’t know for sure until we start immunizing people and see when the cases drop to zero. But compare even those estimates with the current COVID-19 infection rate in Canada, which is about 0.4%.
For most viruses, the kinds of rates needed for herd immunity are rarely achieved with natural infection. We do see some herd immunity through natural infection with colds and, before a vaccine was available, chickenpox. The disease spreads through a community, infecting a high proportion of susceptible people, then disappears once a high enough percentage of the population has had the illness currently or in the past.
For COVID-19, though, we cannot tolerate infection rates to achieve herd immunity through infection. This would mean an unacceptable burden of death, as well as other long-term effects on COVID’s victims that are coming to light: blood clots and organ damage. The health care system would be overloaded for years. But we can achieve herd immunity through immunization.
The second wave will be worse than the first
This is based on the Spanish influenza epidemic of 1918, which coincidentally followed a seasonal pattern similar to that of COVID-19. There was a first wave in the spring, then lower rates during the summer, then a second wave in the fall, much worse and deadlier than the first.
The second wave of Spanish flu was caused by people behaving badly. No law of nature made it inevitable; it was preventable. A lack of public health measures, massive public gatherings, as well as World War I troop movements and returns without quarantine, led to the highest death rate in human history.
The same goes for the second wave of COVID-19, which is already underway as of this writing. Humans caused it, and we can prevent it from worsening. The re-opening of the economy may have been, in hindsight, too quick and too unsafe. Some measures clearly led to clusters of infection that spread. We can get it under control, but we need to return to greater safety measures. A worse second wave is avoidable, not inevitable. It’s a question of political will and public co-operation.
The pandemic may last for years
Is it something in human nature that treats the moment as if it will never end? Maybe it’s evolutionary biology: to survive a crisis, we need to focus on it to the exclusion of all else, so we don’t have the brainpower left over to think that the future may be different.
Others use the crisis to ride their personal utopian hobby-horse: they say the future will need to be different, preferably in their own ideological mould.
Public health authorities warn that infections and safety measures may last several years, but what they don’t say is that the number of infections will decline, outbreaks will become sporadic, and the safety measures will be much less draconian.
It all depends on vaccination. The more effective the vaccines and the more people who get vaccinated, the faster we can get back to the things that matter most to us.
I foresee a scenario like this: vaccines are rolled out in the first half of 2021. As health care workers, the elderly, and vulnerable groups are vaccinated, infection rates start to fall. After everyone is vaccinated, cases drop significantly. If the vaccines are effective enough, the cases drop to zero. The authorities cautiously open up activities and sectors of the economy. They wait for cases to show up. There are still a few outbreaks, which are closely studied. Some vaccines are dropped because they aren’t effective enough, and others are preferred, in a vaccine shakeout. If any viral mutations make a vaccine less effective, they are incorporated into an updated vaccine.
The virus doesn’t go to zero worldwide, but becomes endemic in a few regions, with occasional flare-ups. Eventually the world gets to zero or near-zero cases. Scientists around the globe start tracking coronaviruses in animals, leading to occasional culls of infected animal populations. Coronaviruses are something we learn to live with, like influenza viruses.
We don’t think about how much our lives are affected by diseases past, but they are. We expect decent wages and low prices because the Black Death raised the value of workers. We have screens on our windows to prevent malaria. We wash fruits and vegetables to prevent food-borne illness. We treat drinking water and build sewage systems to prevent cholera. COVID-19 will undoubtedly leave a mark on our society, but we don’t yet know what it will be.