MASKS and VIRAL LOAD – Less severe disease and better immunity?
We know for sure that the rate of infection decreases when masks are worn.Do masks also diminish the severity of an infection if you still get it? Most likely yes.
From MANY animal studies, we know that lower inoculation rates of viruses do result in less severe degree of disease, lower death rates and lower complications.
Studies on humans are very limited since it is unethical to knowingly infect humans with something potentially lethal. There have been a few studies with much less lethal infections which support those animal studies and there are some studies which plan to knowingly expose people to SARS Cov-2 after immunization. Knowingly infecting innocent animals is another thing, but I won’t get into that here.
In an influenza study in humans where healthy volunteers were given differing doses of the virus, there was a correlation between amount of inoculum (number of viral particles) and the severity of disease. A Swiss study showed that soldiers in a group who did not have any social distancing or mask wearing had a 30% rate of infection whereas a group of soldiers who distanced and wore masks had a 0% disease rate. Looking at the 1918 pandemic, the second wave was much worse with a much higher death rate than the first wave, whereas all other pandemics showed the opposite. The feeling is that the overcrowding because of the war, which occurred during the second wave, resulted in a much higher viral load and thus more severe disease.
As far as the SARS Cov 2 virus is concerned, a few animal studies do show a dose-dependent degree of severity of disease. Simulated mask models in hamsters did show lower rates of infection and lesser degree of disease in those masked animals.
We know that with various human viral diseases, the load seems to correlate with severity of disease.
Cruise ships are great examples of what can happen with Covid. On the Diamond Princess, one of the early examples, the rate of asymptomatic positive cases was between 20 and 40%, approximately what the CDC estimates occurs in the human population. On another cruise ship, where masks were handed out and were worn, the asymptomatic infection rate was 81% and there was a lower rate of severe disease with lower cases overall. This strongly suggests that masks may not prevent you from getting exposed, but lower doses of the virus may lead to less severe disease, while maybe providing a similar degree of future protection (see below).
There are many other examples, including meat packing plants and hospitals, where mask wearing resulted, not only in less disease, but higher proportion of asymptomatic infection.
The point is NOT that masks do not provide protection but that, in addition to lowering the rate of infection overall, but if you still get sick, you are much less likely to have a severe disease, indirectly indicating that viral load matters!
BETTER IMMUNITY BECAUSE OF MASKS? It appears so. Although antibody levels do decrease over time, T cells, those responsible for orchestrating the virus specific immune response, persists. A European study has shown that this T Cell immunity persists, many months after infection, much longer than antibody levels remain elevated.
Although there have been reported cases of re-infection, in China, Europe and the US, they are few so there is most likely a prolonged protection from previous exposure. How long? We don’t know yet. We do know that the flu vaccine protects for 4-6 months. We are just past that threshold now but the surge we are now seeing may make that determination difficult.
In over 1000 US counties examined, there is a direct correlation between degree of mandated mask wearing and severity and frequency of disease, including lower death rates in the mask wearing counties.
SO
WEAR YOUR MASK!
It protects you from getting infected.
It protects others from getting infected.
It lowers the degree of severity if you still get infected.
Since there appears to be prolonged protection against reinfection if you get sick and that even asymptomatic cases have measurable antibodies and T Cells, masks will act as a vaccine surrogate until one is available.
Have a great weekend.
Stay safe and be well.
AC