James Coker, Tribune News Service
Many seem to believe that the eventual development of an effective SARS-CoV-2 vaccine will allow us to return to “normal.” If only we can hold on a bit longer, all will be well. But does that view align with science?
The reality is that SARS-CoV-2 will be with us for years to come. Even after a vaccine is available, we will be living with uncertainty far longer than most probably think.
First and foremost, there will be logistical issues to overcome and questions to answer. Who will pay? How much will it cost? Who gets the vaccine first, and why? Finally, will it actually keep us safe?
Food and Drug Administration approval processes and Centers for Disease Control guidelines exist to make sure that all vaccines are safe, and as Peter Marks, director of the FDA Center for Biologics Evaluations and Research, assures us, any FDA-approved vaccine will meet those safety guidelines. But there are other issues to consider.
For one, we need to look at herd immunity and determine how many people in a community need to be immune before the likelihood of person-to-person transmittal is unlikely. If we extrapolate from another highly communicable disease (measles), we see that the required level is very high — somewhere above 90% — while the current FDA guidance for potential COVID-19 vaccines places the bar at 50% or better, equivalent to that of the flu shot.
In other words, if a COVID-19 vaccine is only 50% to 70% effective, achieving herd immunity will be difficult if not impossible.
Several polls (by Pew, Gallup and others) suggest that roughly one in three Americans would refuse a COVID-19 vaccine — even if it were free. Recent measles outbreaks from California to Minnesota to New York underscore the danger of this approach, with all of them occurring in communities with poor vaccination coverage.
A second area of concern involves the virus itself, and it is important that we keep in mind that it is new and we still know very little about it. We can draw on what we know from similar diseases, but that doesn’t mean that this virus will act similarly.
We don’t have answers yet to even simple questions like, “What concentration of antibody in the blood is needed to confer immunity?” And: “Once the body generates antibodies, will they prevent reinfection? Or: “How long will immunity last? (Studies coming out of the UK suggest that COVID-19 antibody levels decline quite rapidly after infection.)
And, of course, we do not yet know how potent a vaccine might be. Will it require a typical two-dose protocol (like Pfizer’s) or will it require regular “booster” shots? One that requires regular boosters will place a heavier load on the health care system, as some will inevitably forget to get a booster and will get infected or reinfected.
A third issue to consider is the effectiveness of a vaccine against multiple strains of COVID-19. Studies of people who have been reinfected suggest that this might be due to genetic changes in the virus. So, a vaccine that is effective against one strain might not confer immunity to another. Any vaccine that is effective in the long term will probably need continuous adjustment, similar to the yearly flu vaccine, with strains evaluated yearly and changed depending on their presence/prevalence in the environment.
Getting this right will require many years of active research and data collection. Any margin of error will also be much lower as the fatality rate for COVID-19 is higher than that of the seasonal flu.
For all of these reasons and more, a return to “normal” is not as close as some seem to think. We must insist that our elected officials continue to invest in keeping us safe, launching a coordinated campaign to encourage people to get vaccinated, increase the number of people that are tested daily and conduct contact tracing on those who test positive. It also means taking equally vital if less visible steps like tracking the strains of SARS-CoV-2 as we do with influenza.
Each of these efforts will require dedicated funding at all levels of government and will only happen if we demand them from the people who represent us. If we don’t, this health crisis could be with us for years to come.