From time to time, my primary care physician Dr. Alex Lickerman posts articles on his website from about what’s going on with the pandemic, concentrating on the scientific research and what it means. The latest post on the website, below, “lays out the evidence for wearing masks, talks about the development of a vaccine, and answers questions about the validity of the rapid nasal swab test.” You can read it as a whole, or skip to the “bottom line” in each section. I’ll simply list the sections (Q&A’s) and the bottom lines.
Alex has kindly volunteered to answer readers’ questions about the pandemic, about vaccinations, about masks, and anything to do with the virus and how we should deal with it as individuals and as a society. So feel free to put your questions in the comments, and Alex will answer them as he has time.
Click on the screenshot to read the post:
The sections and “bottom lines” (quotes are indented). Any take I have will be flush left, and of course each section below is followed in Alex’s post by an extensive discussion of the medical/scientific data.
Question: Will the wearing of masks in appropriate circumstances slow the pandemic?
BOTTOM LINE: The only way we’ll ever know for certain if mask-wearing by asymptomatic people, in the right circumstances, will reduce the spread of SARS-CoV-2 would be to prospectively assign a region (e.g., a city) to wear masks and compare its rates of infection over the same time to another region where people were assigned not to wear masks (and measure the compliance of each). The impossibility of conducting such a study at this point is obvious. Therefore, we’ll likely never be able to conclude with 100 percent certainty that mask-wearing in the right circumstances will slow the progression of the pandemic. But when we consider the sum of the evidence above, we conclude that mask-wearing by asymptomatic people, in the right circumstances, is likely to slow the progression of the pandemic.
Question: Who should wear masks, then?
. . . .When you consider this data together, you have what seems on the surface to be a good argument for not wearing masks to reduce the spread of COVID-19 if you’re asymptomatic.
BOTTOM LINE: But it’s not. Here’s why: a 21 percent prevalence of asymptomatic SARS-CoV-2 infection represents 57.9M people infected. If each of those 57.9M infected people has a 0.33 percent chance of spreading the infection without wearing a mask and does so, it would amount to roughly 191,070 transmitted infections! (Even if our estimate of the number of asymptomatic infections is off by a factor of 10, this would still amount to 19,107 infections.) We don’t know to what degree wearing a mask will decrease the risk down from 0.33 percent, but even a small amount would translate into a large number of people. Thus, while the impact of one asymptomatically infected person not wearing a mask is small, the impact of all asymptomatically infected people not wearing masks may be large. The logic of collective action requires that individuals act as if their contribution is greater than it is because only that way do enough individuals act in such a way that yields the protection society needs. We all need to tolerate inconvenience to contribute to the greater good.
Alex also discusses which masks are best. So far there are data only for which masks keep you from spreading viruses through respiratory droplets. For this N95s are the gold standard, but plebes like us can’t easily get them. He recommends using surgical masks to prevent infecting others, though most other masks seem to be about as good. And the best masks to protect YOU are probably the best masks for protecting others against you, though this isn’t 100% certain. Avoid knitted masks and single-layer cloth masks. I covered some research on this in a post a few weeks ago.
To me, this is the most depressing part, but I can’t quarrel with the argument:
Question: Will we have a safe, effective vaccine for COVID-19, and if so, when?
Answer: Probably. But likely not until the Summer of 2021 at the very earliest.
BOTTOM LINE: Currently, there are over 140 COVID-19 vaccines in development. Given the statistics we quoted above, that means we should end up with 14 viable vaccines. There’s one RNA vaccine being tested in a Phase III trial right now with 30,000 volunteers being given the vaccine. But we predict it will take us at least until mid- or late-2021 to determine if it’s a winner because it will take at least that long to make sure the vaccine is safe and effective. Remember, the risk of adverse reactions to vaccines needs to be substantially lower than the risk of adverse reactions to medications. This is because: 1) the number of people vaccinated will be much greater than the number of people given a medication (medications for diseases are given to at most millions of people; a vaccine for COVID-19 will be given to billions of people), so even small risks of harm can mean harm is done to millions of people, and 2) the vaccines are given to healthy people, not people already suffering from a disease. Thus, the risk of adverse events from the vaccine must be compared to the risk of not just contracting the disease but of experiencing a severe adverse outcome (i.e., severe, chronic morbidity or death). So, in the case of COVID-19, if we’re considering immunizing a 12-year-old child, for example, whose risk of dying from COVID-19 is literally only 0.022 percent, the risk of a severe adverse reaction to the vaccine needs to be far below that.
Unfortunately, the history of vaccine development is replete with stories of harm. One vaccine developed against respiratory syncytial virus (RSV) in the 1960s actually caused a form of immune enhancement where the disease was worse in vaccinated children, even killing two who’d been vaccinated. In 1955, Cutter Laboratories, a small pharmaceutical company that manufactured a polio vaccine, released vaccines contaminated with fully live virus due to manufacturing errors and poor government oversight, resulting in an estimated 40,000 children being infected with polio. Two hundred victims were permanently paralyzed, and ten of them died.
We mention these cautionary tales not to add fuel the anti-vaccine movement fire, but to highlight the importance of doing the science correctly, of not rushing inadequately tested vaccines to market. The reason vaccines are among the safest of medical interventions available is because they undergo such long and rigorous safety testing. As candidates come off the pipeline, we’ll review their efficacy and safety data and make recommendations about them.
This section has a good precis on how vaccines are both developed and tested. There’s also a nice graph in this section showing the reduction of nine childhood diseases after vaccination was introduced—good ammunition against antivaxers. Alex concludes: “Immunization is one of the most effective—and safest—public health measures that exist. The prevalence of infections from diseases for which we now vaccinate children has declined by ninety percent (see chart below of effectiveness of routine childhood vaccinations). There are literally no other interventions in medicine that are as effective as vaccination.”
Question: Are rapid tests worth doing, especially because the results are returned so much more rapidly
Answer: Only if the rapid test comes back positive can you believe it.
BOTTOM LINE: We don’t recommend people get a rapid test. Even though results take longer with the PCR test, a negative PCR test is more likely to be accurate. We know only one rapid test with a zero false-positive rate. Other rapid tests may not perform nearly as well.
This is the tenth in Alex’s series of posts on coronavirus and the pandemic; you can see all the links at the bottom of this post. There’s a lot more to read if you’re interested.
So, if you have questions—my latest one, which I asked Alex yesterday, was “is it safe to get a haircut, and how should ensure that the experience is the safest possible?”—put them in the comments below and then check back in a while to see if they’ve been answered.
Thanks to Alex for offering his analyses and advice to the readers.