One of the biggest challenges facing scientists, public health experts, and society itself during the COVID-19 crisis is the need to develop an effective vaccine for the virus that causes the disease. You might have heard that COVID-19 vaccine trials are underway in many research labs either in University or Government National Labs. What exactly is being tested? How much longer will these tests take? And when can we expect a vaccine against the novel coronavirus? These are the typical questions that many people have.
Researchers around the world are racing to develop just such a vaccine. Even so, scientific and medical authorities say it may be at least a year before one is ready.
When did COVID-19 Originate?
Retrospective investigations
by Chinese authorities have identified human cases with onset of symptoms in
early December 2019. While some of the earliest known cases had a link to a
wholesale food market in Wuhan. Up to now, nearly 695,000 people have died
worldwide and more than 18 million people have been infected into 213 countries
and territories.
How do vaccines typically work
in the human body?
While vaccinating the body is
exposed to various proteins, carbohydrates, and other molecules that are
present in the virus. But it is done in a setting that is non-pathological.
That is, the vaccine is recognized by your immune system, and it educates your
immune system about proteins from the offending virus. This enables your immune
system to mount a response with antibodies or T-cells when the actual pathogen
comes along.
Current Research in Covid-19
Vaccine
It is very hard to predict how
many labs are working on the Covid-19 vaccine.
Most of the labs do not want to expose their research to anybody until it has
been published in the Journals or patented. Among many research works, one that has
received a serious amount of attention is being developed by the Boston biotech
company “Moderna” and the “National Institutes of Health”. It's an mRNA
vaccine. This approach involves the blueprints for virus proteins, which can be
introduced into human cells to start the education process for the immune
system. You're not actually introducing the viral proteins themselves, just the
template for those proteins.
RNA vaccines are probably very
safe to administer and very quick to develop and scale up. This is why, within
a few weeks of COVID-19 becoming a public threat, Moderna already had a
candidate that it could test in people. That is the upside. The downside is
that no mRNA vaccine has ever been approved by the U.S. Food and Drug
Administration for humans. There's an inherent risk from having an entirely
different approach that hasn't been validated previously.
Another vaccine approach is
called hyperimmune globulin, also known as the "blood bag" option.
Researchers at Johns Hopkins University are attempting this approach. Here's
how it would work. When a person is infected and successfully fights off the
virus with proteins called antibodies, you can take plasma from that person and
create a serum with a high concentration of the right antibodies. This is a
very old approach, utilized on a large number of conditions. Very well
validated. The downside is that the supply of effective hyperimmune globulin is
going to be extremely limited, due to the limited number of suitable antibody
donors, among other factors. In my opinion, it's a great short-term measure,
but it may not be a sustainable, scalable approach.
What about a mutation in the
virus genes?
One of the great challenges in
the development of vaccines is that viruses can mutate their genes. Recent news
reports indicate that COVID-19 has been slow to mutate, which may give a
potential vaccine more staying power. Theoretically, if the mutation rate is
slow, then the ability of the virus to mutate around
a vaccine would
also be slow—and population-level immunity would be high. But there may be
other immune
system mechanisms that we don't understand. If antibody levels after
vaccination don't remain high over a long period of time, for example, then
immunity goes down and reinfection is possible.
The hope of development of a vaccine
As many scientists are focused on
this pandemic causing virus, so we can be hopeful that something will turn up
even faster than a year from now. But, one-year timeframe, although it may not
feel fast enough for many of us, it's actually quite fast for bringing any kind
of novel therapeutic to people. Some things cannot speed up. Enrolling
patients in a trial takes time. Obtaining materials for a clinical trial takes
time. But with so many approaches being explored, we can hope that it is going
to turn up and be successful.
World Health Organization
American Chemical Society
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