Covid Commentary: Unpredictable Paths – Claire McGreal Interviews Physician and Virologist Frank Chisari

Claire: These COVID variants seem to move from the east coast to the west. I have been watching the case counts rise daily in MA.  Guess we need to stay very careful and ever vigilant.  If you have any further advice, we are all ears.

 

Frank:  Your guess is correct. The

Frank Chisari. Photo, Linda Chisari.

airborne SARS-CoV-2 virus is so easily transmitted from person-to-person, and it replicates so rapidly in their respiratory tracts that it produces huge numbers of mutations per day in each infected person. A small fraction of those mutations will mask the virus from that person’s immune response which gives the mutant virus particles a survival advantage over the rest of the virus particles that haven’t acquired the immune evasive mutations in that person. So, pretty quickly, those immune evasive variants become the dominant population in that individual.

 

Then, because the mutant virus is so easily spread through the air to anyone in the area, it soon becomes the dominant strain in the local population. Along the way, these mutants often acquire mutations that make them less pathogenic (cause milder disease). That’s what “smart” viruses do because the newly infected persons feel okay, so they go to school, work, restaurants, theaters, take vacations, etc., without knowing they’re infected, and that spreads the virus widely and quickly throughout the population and ultimately all over the world.

 

Claire: Are the elderly more vulnerable?

 

Frank: Once that strain of virus spreads widely enough, however, it can reach elderly, diabetic, asthmatic, leukemic, transplant patients, etc., who can get seriously ill from the same, otherwise benign, virus that may cause nothing more serious than “common cold” symptoms in young, healthy people. The virus can spread to such high numbers in these susceptible patients that they require hospitalization, and possibly even die from what seems like a mild infection in most of its victims. So, even a virus that seems innocuous can kill a lot of susceptible immunocompromised and, especially, elderly people if it spreads sufficiently widely.

 

Basically, what I’ve just described is a very common scenario, especially for respiratory viruses. Indeed, the virus will continue to mutate and evade the immune response until the scientific community develops a vaccine the virus cannot evade. That can happen, at least theoretically, if the mutations that allow the mutant virus to evade the immune response also prevent the virus from either reproducing itself or from spreading to others.

 

Claire: So, what are the best ways to protect ourselves?

 

Frank: Bottom line: (1) get vaccinated and boosted to protect yourself against any vaccine-sensitive variants that still linger in the population; (2) avoid crowds as much as possible especially indoors; (3) wear a good quality N95 mask whenever you’re indoors in public spaces; and (4) stay outside as much as possible.

 

This doesn’t mean you have to become a hermit. For example, I just flew to Salt Lake City and back last week on a fishing trip with a buddy who had been immunized and boosted (as was I) and wore an N95 mask (as did I). I spent several days eating inside a restaurant with a lot of guys who behaved like they thought they were immortal. Fewer than 1% of people in the terminals and airplanes were masked. And nobody granted me 6 feet of space in any of those places. Also, I rode in our unmasked guide’s pickup truck with the windows closed at the beginning and end of each fishing day. So, I think I was probably exposed to the virus quite a bit during that trip. Despite all of that exposure, neither my buddy nor I got infected according to antigen tests we took while we were away and 5 days after we got back home, probably because we were fully vaccinated and boosted, wore N95 masks under all those conditions (except while eating) and used hand sanitizer often.

 

Claire: What is your prediction for how long this pandemic is going to last?

 

Frank: I don’t think we will be rid of SARS-CoV-2 for a very long time. Nonetheless, given that it has already mutated away from being highly deadly in most people (which, again, is what “smart” viruses do), and despite the fact that we may not be as well protected by vaccines against new strains of the virus, it’s quite possible to reduce the risk of getting infected by following the simple precautions I described above. And since the virus has also evolved to be less pathogenic, most people who do get infected will most likely have cold and flu-like symptoms and not need to be hospitalized. And if they are immunocompromised or elderly and do get very sick, there are antiviral drugs available that, if taken early, can keep most of them out of the hospital.