Wednesday, October 28, 2020

A COVID Vaccine Reality Check

HHS Sample Framework For Vaccine Distribution 


While I am a decidedly pro-vaccine blogger - one who gets a flu shot every year and has plans to get the shingles vaccine in the next few months - I am also a vaccine realist, and I wince a little every time an as-yet unproven COVID-19 vaccine is trotted out as being the panacea for our current pandemic. 

The average American (and for that matter, global citizen) has been led to believe - by politicians, the media, and `Forward Looking' & `Aspirational' Vaccine Press Releases - that a safe and effective COVID-19 vaccine is `just around the corner', and that once that happens life will return to `normal'.

But of course, it's not going to be that simple, even assuming that one or more COVID vaccines receive EUA (Emergency Use Authorization) by the end of the year. 

Left out (or glossed over) has been the reality that in the opening months of 2021, vaccine quantities will be quite limited and some groups (i.e. children, pregnant women) - who have not (as yet) been part of vaccine safety trials - may not be offered the vaccine at all (see CDC: 10 Things Healthcare Professionals Need to Know about U.S. COVID-19 Vaccination Plans).

Vaccine recipients will likely need two shots, spaced roughly 28 days apart, which will further decrease the number of people that can be immunized early on. The logistics of how a vaccine will be dispensed, and who will be prioritized to get it first (HCWs, 1st Responders, the Elderly?), have not yet been announced. 

As we've discussed previously (see Remembering An Emergency Pandemic Vaccine Program That Went Awry), mounting a nationwide emergency vaccination campaign is a massive undertaking, and one that could easily be derailed by bad publicity or vaccine hesitancy. 

While the safety of any new vaccine will be paramount, and we ought to have reasonable data on that (at least for cohorts involved in the safety trials), we may know very little about the effectiveness of any experimental vaccine at the start. 

It normally takes a couple of years (at least) to assess the effectiveness of a new vaccine, and while the UK Has Approved Human COVID-19 Vaccine Challenge Studies, it will be limited in size, only conducted on young and healthy adults (age 18-30), and the results probably won't be published until May of 2021. 

While this study could provide important data, how well it will apply to more `at risk' cohorts is unknown.  The immune response mounted by 18-30 y.o. healthy adults to the flu vaccine is usually substantially greater than by those over 65.

At this point - even assuming a COVID-19 vaccine can be produced - no one can predict how effective it will be in preventing infection, or lowering the severity of illness, in any age group or demographic. Nor do we know how long any protection from the vaccine will last. 

Admittedly, even a vaccine that is only 50% effective in preventing infection, or even one that substantially reduces the odds of developing severe disease, would be an important tool in fighting this pandemic. 

But most people expect more from a vaccine, particularly given how much hype this one has received.  A modest success could easily appear as a massive failure to most Americans, who are being primed to expect a `magic bullet' against COVID-19. 

While most reputable scientists have been careful not to over promise on a COVID vaccine, many have said they are `hopeful' that a safe and effective vaccine can be ready by the end of the year. Left largely unsaid, however, are 1) at what quantity and for who 2) and what constitutes `effective'

While instilling hope is important, these are the types of omissions that tend to come back and bite us in the behind. 

I've always believed it is better to under-promise and over-deliver, than the other way around.  Things happen, plans go astray, and sometimes the wheels fall off.  The more you promise, the less tolerance there will be for failure. 

All of which brings us to an article by Liz Szabo and JoNel Aleccia - published by Kaiser Health News & NBC news - that quotes Dr. William Schaffner, Dr. Peter Lurie, Dr. Arnold Monto, and others on the public's unreasonable expectations for the first generation of COVID-19 vaccines. 

Due to its length, I've only posted the link, so click it to read this article in its entirety.   I'll have a brief postscript when you return.