Engineering Ethics Blog: The COVID-19 Vaccine: When, Where, and Who?


 

Most experts agree that the only thing which will put the
current COVID-19 pandemic to rest is some kind of vaccine.  One firm—Pfizer/BioNtech—has progressed to
what is called a Phase 3 trial, which involved about 43,000 people who took it
with apparently no serious side effects. 
There is still a long way to go even with the most advanced projects,
because achieving “herd immunity”—enough immune people to discourage
the virus from spreading—may require on the order of several billion
doses.  And many of the prospective
vaccines require two injections spaced weeks apart, which further complicates
matters.

 

Engineers are familiar with tradeoffs that are usually
imposed by economic restrictions.  When I
was a young engineer just out of college, I was teamed with an older and more
experienced engineer, and one day we were talking about various possible ways
to tackle a certain problem in a new design we were working on.  I described three or four different ways to
tackle it that I thought were pretty clever, but he seemed unimpressed.  Finally, I asked him why he wasn’t more
excited about these innovative ideas I was proposing.

 

“Heck, I can build one of anything!  The real challenge is making thousands of
them work at a price we can afford.” 
The harsh realities of the marketplace had educated him to look not just
for technically sweet ideas, but for ideas—new, old, or otherwise—that would do
the best job for the least money.  That taught
me that having clever ideas—or one dose of a highly effective vaccine—is only a
small step toward solving a real-world engineering or technical problem.

 

Making a billion high-quality vaccine doses in a short time
is a challenge that hasn’t been discussed much so far.  But supposing that vast production problem is
overcome, and reliable vaccine doses begin to enter the pipeline, who is going
to get them first? 

 

An interesting study cited by a recent BBC article says that
the first doses should go to different groups, depending on how effective the
vaccine is.  No vaccine is 100%
effective, and this is especially true of virus vaccines.  The annual flu-virus vaccine that millions of
people get is rarely more than 60% or so effective, depending on the particular
year and the mix of viruses that show up after the vaccine is developed. 

 

There are different ways to measure the effectiveness of
vaccines.  One way is to measure how many
people who are vaccinated and then exposed to the virus develop symptoms.  Another way is to measure how likely a
vaccinated and exposed person is to spread the disease to others, whether or
not they manifest symptoms.  The study’s
authors point out that if you developed a vaccine that was only 30% effective
in preventing symptoms, it would fall below the U. S. Food and Drug
Administration’s 50% threshold and wouldn’t even be approved.  But if it happened to be 70% effective at stopping
people from spreading the virus, it would actually do more good than a
different vaccine that prevented symptoms with 100% effectiveness but allowed
the virus to spread.

 

That is why there is no single answer to the question,
“Who should get the vaccine first?” 
If it is most effective in preventing the virus from spreading, then the
target population should be the ones who spread it the most.  Currently that appears to be older children
and younger adults, say between 10 and 35. 
Few people in that group die of the virus, but just because many of them
have either mild symptoms or are asymptomatic, they spread it very easily. 

 

On the other hand, if the vaccine is good at preventing
symptoms but not so good at stopping the spread, you probably want to target
the population that is most vulnerable to the disease:  people in rest homes and over 65.  That will save the most lives in the short
term, while giving us time to vaccinate the rest of the population to approach
the goal of herd immunity.

 

Any way you slice it, we face a very long uphill battle in
fighting this disease.  In some countries
such as the U. S. and China, the expense of buying and distributing the vaccine
is relatively trivial compared to other things the government is doing.  But in poorer countries, vaccinating the
majority of the population with anything is a major challenge, and so we can
expect the disease to hang around in pockets long after it has been controlled
in more economically well-off places.  So
the last thing to go may be travel restrictions concerning COVID-19, at least
to some countries where it may not be controlled for several more years.

 

Within a given country, the distribution of the vaccine may
be implemented mainly by the government, mainly by private enterprise, or more
typically by a combination of the two.  As
it is in the interests of every government to free its citizens from the threat
of COVID-19, substantially free distribution would seem to be a no-brainer,
although there are practical obstacles to that as well.  Certain minority populations have been
disproportionally affected by COVID-19, and the U. S. National Academies of
Science, Engineering, and Medicine has stated that there is a “moral imperative”
to make sure that this imbalance is addressed in any proposed distribution
scheme. 

 

And last but not least, there is the problem that not
everybody is going to want to be vaccinated.  We are a long way from the 1950s, when Jonas
Salk was universally praised as a god-like hero and millions of U. S. citizens
gratefully took their children to receive polio vaccine injections without
raising even a quibble concerning its safety. 
Nowadays, the pronouncements of experts always inspire somebody on the
Internet to say, “Sez who?” and the small but vocal opponents of any
kind of vaccination have persuaded lots of people at least to hesitate before believing
uncritically anything an expert says. 

 

Even with all these uncertainties, it does look like we we get
a vaccine sometime, and eventually it will begin to slow down the spread of
COVID-19.  As far as I’m concerned, it
can’t come too soon.

 

Sources:  The BBC published the article
“COVID:  How close are we to a
vaccine?” on Nov. 12, 2020 at https://www.bbc.com/news/health-51665497.  The New York Times published “Who
should get a COVID-19 vaccine first?” at https://www.nytimes.com/2020/11/05/magazine/who-gets-covid-vaccine.html
on Nov. 5, 2020. 



Source link