Covid 19: Where are we now and what have we learned:
A look back

If we’ve learned one thing over the past 2 years, it’s that the only predictable thing is that this pandemic is unpredictable. Viruses mutate in nature constantly. Most mutations do not amount to anything significant, but given time and endless probabilities, an occasional mutation will make a virus different enough that it might escape a body’s natural immunity or the immunity conferred by vaccinations. The virus might be more easily transmissible, more virulent, or both.

The Omicron variant was found to have up to 50 mutations. Previous research had shown that some of these mutations enabled coronaviruses to grab onto cells more tightly. Others allowed the virus to evade antibodies which serve as an early line of defense against infection. Lab studies on rats and subsequent studies on human lung tissue, however, revealed that Omicron was less likely to infect lung tissue which might explain why this seems to cause less severe disease than the prior dominant variant, Delta. The level of virus, however, in the nose and throat infected with Omicron, was as high as with the Delta variant. Omicron spreads more quickly but overall will cause less severe disease. However, that does not mean we do not have to be concerned about Omicron because it is less virulent. More people being infected means
more hospitalizations and a greater number of deaths.

The other issue is whether previously vaccinated people are protected against Omicron. There is little doubt that fully vaccinated people are getting sick with Omicron, but the rise in hospitalizations and deaths is occurring primarily in the unvaccinated population.

So what does this all really mean?

The vaccines are working. Most people who are being hospitalized are unvaccinated and although people who have been double vaccinated and even boosted still are getting Covid, the illness tends to be mild and rarely leads to hospitalization and death.

Recent evidence suggests that the masks most people are using are not nearly as protective as they should be. The current CDC recommendation is to use either an N95 or KN95 mask or to use a cloth mask along with a surgical type mask to minimize the risk of infection.

Another issue that has yet to be clearly delineated is what to do once you are exposed to the virus and what to do if you become symptomatic. Originally, the CDC recommended a 10-day quarantine once exposed. They have now changed that to 5 days from exposure but do not recommend testing at the end of 5 days. Instead, they suggest you wear an appropriate mask for the next 5 days when you are around other people. Is the decision not to test a good idea? From a purely medical perspective, perhaps not. However, minimizing the negative impacts that long quarantine periods have on the economy and education, which can have deleterious secondary effects on people’s health and wellbeing, is a factor that is important to take into account.

Are there therapeutics available once someone is infected? The quick answer is yes but these are not readily available yet. Monoclonal antibody infusion within 5 -10 days might be useful but the only one shown to help with Omicron has been Sotrovimab. This is only used right now in people with medical conditions that put them at high risk and immunocompromised patients.

Both Merck and Pfizer have pills that have received the EUA (emergency use authorization) from the FDA. Merck’s pill has been shown to reduce hospitalization and death in cases of Covid-19, but only in cases where other FDA-authorized Covid treatments are not accessible or clinically appropriate. Pfizer’s Paxlovid appears to have advantages in both efficacy and safety in reducing hospitalizations and mortality. Both should only be used in patients with a high risk for hospitalization or death. Unfortunately, the rollout for both has taken quite some time since production can take months. Lastly, Evusheld which is a combination of 2 monoclonal antibodies, has been shown to be effective in immunocompromised patients as prophylaxis to prevent infection with Covid.

How do we prepare for possible new surges of Covid, potentially with a more virulent strain or even another pandemic secondary to another virus?

1: This is a public health issue and as such, it is incumbent on everyone to follow rules of social distancing and masking with the correct mask where and when necessary and possible.
2: Continue to modify the mRNA vaccines as needed to meet new threats from newer or different strains. It is imperative that vaccines be available worldwide as mutations occurring in underdeveloped and less vaccinated populations will only lead to continual infections worldwide.
3: Continue to develop better and more accessible therapeutics that can be mass-produced even if production has to cross company lines.
4: PPE’s or personal protective equipment must be available in sufficient amounts so that there is no shortage of healthcare workers and first responders.
5: We must ensure testing is available to everyone in a timely fashion.