Vaccine can help save lives
Finally declaring the coronavirus a pandemic, all eyes have turned to the prospect of a vaccine because only a vaccine can prevent people from getting sick
Adnan Shafi
About 35 companies and academic institutions are racing to create such a vaccine, at least four of which already have candidates they have been testing in animals. The first of these – produced by Boston-based biotech firm Moderna – will enter human trials in April.
All vaccines work according to the same basic principle. They present part or all of the pathogens to the human immune system, usually in the form of an injection and at a low dose, to prompt the system to produce antibodies to the pathogen. Antibodies are a kind of immune memory which, having been elicited once, can be quickly mobilized again if the person is exposed to the virus in its natural form.
Traditionally, immunization has been achieved using live, weakened forms of the virus, or part or whole of the virus once it has been inactivated by heat or chemicals. These methods have drawbacks. The live form can continue to evolve in the host, for example, potentially recapturing some of its virulence and making the recipient sick, while higher or repeat doses of the inactivated virus are required to achieve the necessary degree of protection.
Some of the Covid-19 vaccine projects are using these tried-and-tested approaches, but others are using newer technology. One more recent strategy – the one that Novavax is using, for example – constructs a “recombinant” vaccine. This involves extracting the genetic code for the protein spike on the surface of Sars-CoV-2, which is the part of the virus most likely to provoke an immune reaction in humans and pasting it into the genome of a bacterium or yeast – forcing these microorganisms to churn out large quantities of the protein. Other approaches, even newer, bypass the protein and build vaccines from the genetic instruction itself. This is the case for Moderna and another Boston company, CureVac, both of which are building Covid-19 vaccines out of messenger RNA.
There are good reasons for that. Either the candidates are unsafe, or they’re ineffective, or both. Screening out duds is essential, which is why clinical trials can’t be skipped or hurried. Approval can be accelerated if regulators have approved similar products before.
The annual flu vaccine, for example, is the product of a well-honed assembly line in which only one or a few modules have to be updated each year. In contrast, Sars-CoV-2 is a novel pathogen in humans, and many of the technologies being used to build vaccines are relatively untested too. No vaccine made from genetic material – RNA or DNA – has been approved to date, for example. So the Covid-19 vaccine candidates have to be treated as brand new vaccines.
An illustration of that is a vaccine that was produced in the 1960s against the respiratory syncytial virus, a common virus that causes cold-like symptoms in children. In clinical trials, this vaccine was found to aggravate those symptoms in infants who went on to catch the virus. A similar effect was observed in animals given an early experimental Sars vaccine. It was later modified to eliminate that problem but, now that it has been repurposed for Sars-CoV-2, it will need to be put through especially stringent safety testing to rule out the risk of enhanced disease.
Currently, Caught in this endless nonstop news swirl, many people — parents and others — can probably understand what it’s like to be hoping — and waiting — and maybe even praying — for a vaccine. It’s a moment that should connect us with our not-too-distant history, and maybe make us wonder whether we’ve lost some valuable perspective.
In 1955, when the first clinical trials showed that Jonas Salk’s new polio vaccine was “safe, effective and potent,” it was front-page headline, above-the-fold news. The New York Times offered this: SALK POLIO VACCINE PROVES SUCCESS; MILLIONS WILL BE IMMUNIZED SOON; CITY SCHOOLS BEGIN SHOTS APRIL 25.
“It was a remarkable moment when an entire nation breathed a sigh of relief that this hideous childhood disease could be prevented,” said David Oshinsky, a professor of medicine at N.Y.U. Langone Health, and the author of “Polio: An American Story.” “When that announcement was made, church bells chimed, factory whistles went off, adults ran into the street and began hugging each other.”
Can you imagine the sigh of relief when there’s an effective coronavirus vaccine? Given the intensity of the news cycle right now, it’s not actually so hard to imagine we might have an international moment like the one that came when the Salk trial results were announced: banner headlines, church bells ringing. A medical V-Day, where V meant both vaccine and victory, over a feared and previously deadly enemy.
Vaccines have given us such remarkable peace of mind that we have come to take them for granted. Can we really any longer imagine the world before vaccines? Imagine for a minute what it was like when the virus out there was smallpox, a much deadlier epidemic disease than Covid-19. Or more recently, when the virus out there was polio, which regularly caused paralysis and death in children.
People still had to go about their business and make their decisions about every detail of daily life: Attend a social gathering? Let your kid go to the swimming pool on a hot day?
Vaccines give us a way to protect ourselves individually, but they also give us a way to create a safer world. Smallpox vaccine was not only a person-by-person triumph but a huge international human victory over an accumulated historical tide of human misery and death.
People have lost that sense of awe and gratitude for both the individual safety that vaccines represent, and also for the glorious communal project of collectively wiping out a source of pain and disability and death.
A mix of legacy drugmakers and small startups have stepped forward with plans to develop vaccines or treatments that target the infection caused by the novel coronavirus.
COVID-19, which was first detected in December in Wuhan, China, has sickened more than 100,000 people worldwide and killed at least 3,400. There are no Food and Drug Administration-approved vaccines or therapies for the disease.
Accordingly, pandemics tend to hit hardest those countries that have the most fragile and underfunded healthcare systems, there is an inherent imbalance between need and purchasing power when it comes to vaccines. During the 2009 H1N1 flu pandemic, for example, vaccine supplies were snapped up by nations that could afford them, leaving poorer ones short. But you could also imagine a scenario where, say, India – a major supplier of vaccines to the developing world – not unreasonably decides to use its vaccine production to protect its own 1.3 billion-strong population first, before exporting any.
If we get a vaccine for the coronavirus, it will immediately make our world a safer, easier, more reassuring place once again. Science will have solved a problem so that we can once more walk (and fly and sail) more comfortably through the world — at least until the next problem comes along
(The writer is a student of English literature. He is a regular contributor for ‘Kashmir Vision’)
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