What happens if a coronavirus vaccine is never developed? It happened before

0
67


But there is another possibility, in the worst case, that no vaccine will ever be developed. In this result, the hopes of the public are raised several times and then shattered, because the different solutions proposed fall before the last obstacle.

Instead of destroying Covid-19, societies can learn to live with it instead. Cities would open slowly and certain freedoms would be restored, but on a short leash, if the recommendations of the experts were followed. Testing and physical tracing will be part of our life in the short term, but in many countries, an abrupt instruction to self-isolate could occur at any time. Treatments could be developed – but disease outbreaks could still occur each year, and the global death toll would continue to climb.

“There are viruses against which we still don’t have vaccines,” says Dr. David Nabarro, professor of global health at Imperial College London, who is also a special envoy to the World Health Organization. on Covid-19. “We cannot make the absolute assumption that a vaccine will appear, or if it appears, if it will pass all efficacy and safety tests.

The schedule for a coronavirus vaccine is 18 months. Experts say it's risky

“It is absolutely essential that all societies around the world put themselves in a position where they are able to defend themselves against the coronavirus as a constant threat, and to be able to devote themselves to social life and economic activity with the virus among us, “Nabarro told CNN. .

Most experts remain confident that a Covid-19 vaccine will eventually be developed; partly because, unlike previous diseases like HIV and malaria, the coronavirus does not mutate quickly.

Many, including the director of the National Institute of Allergies and Infectious Diseases, Dr. Anthony Fauci, suggest that this could happen in a year to 18 months. Other figures, like England’s chief medical officer Chris Whitty, have veered to the furthest end of the spectrum, suggesting that a year may be too soon.

But even if a vaccine is developed, making it grow within one of these times would be a feat never achieved before.

“We have never accelerated a vaccine in a year to 18 months,” Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, told CNN. “That doesn’t mean it’s impossible, but it will be a heroic feat.

“We need plan A and plan B,” he says.

When vaccines don’t work

In 1984, the United States Secretary of Health and Human Services, Margaret Heckler, announced at a press conference in Washington, DC, that scientists had successfully identified the virus which later became known as HIV – and predicted that a preventive vaccine would be ready to be tested in two years.

Almost four decades and 32 million deaths later, the world is still waiting for an HIV vaccine.

Instead of a breakthrough, Heckler’s request was followed by the loss of a large part of a generation of gay men and the painful flight of their community to Western countries. For many years, a positive diagnosis was not just a death sentence; he assured that one would spend his last few months abandoned by their communities, while doctors wondered in medical journals if HIV patients were even worth saving.

Protester Mark Milano was arrested during an AIDS demonstration in Washington DC in 1994.

Research did not end in the 1980s. In 1997, President Bill Clinton challenged the United States to find a vaccine within a decade. Fourteen years ago, scientists said that we were still about 10 years away.

The difficulties in finding a vaccine started with the very nature of HIV / AIDS itself. “The flu can change from year to year, so the natural infection or vaccination from the previous year doesn’t infect you the next year. HIV does it in one infection, “said Paul Offit, a pediatrician and infectious disease specialist who co-invented the rotavirus vaccine.

“It keeps mutating in you, it’s like being infected with a thousand different strands of HIV,” Offit told CNN. “(And) while it mutates, it also paralyzes your immune system. “

HIV poses very unique challenges and Covid-19 does not have its level of elusiveness, which makes experts generally more optimistic about finding a vaccine.

Lessons from the AIDS epidemic for the coronavirus

But there have been other illnesses that have confused scientists and the human body. An effective dengue vaccine, which infects up to 400,000 people a year according to the WHO, has eluded doctors for decades. In 2017, a large-scale effort to find one was suspended after it was found to worsen the symptoms of the disease.

Likewise, it has been very difficult to develop vaccines against common rhinoviruses and adenoviruses – which, like coronaviruses, can cause cold symptoms. There is only one vaccine to prevent two strains of adenovirus, and it is not commercially available.

“You have high hopes, then your hopes are dashed,” says Nabarro, describing the slow and painful process of developing a vaccine. “We are dealing with biological systems, we are not dealing with mechanical systems. It really depends so much on how the body reacts. “

Human trials are already underway at the University of Oxford in England for a coronavirus vaccine made from a chimpanzee virus, and in the United States for a different vaccine produced by Moderna.

However, it is the testing process – not development – that often delays and slows vaccine production, adds Hotez, who has worked on a vaccine to protect against SARS. “The hard part is showing that you can prove it works and that it is safe. “

Plan B

If the same fate happened to a Covid-19 vaccine, the virus could stay with us for many years. But the medical response to HIV / AIDS still provides a framework for living with an illness that we cannot eradicate.

“In the area of ​​HIV, we were able to make it a chronic disease with antivirals. We have done what we always hoped to do with cancer, ”said Offit. “It was not the death penalty as it was in the 1980s.”

The revolutionary development of a daily preventive pill – pre-exposure prophylaxis or PrEP – has since protected hundreds of thousands of people at risk of contracting HIV.

A number of treatments are also being tested for Covid-19, while scientists are looking for a Plan B in parallel with the ongoing vaccine trials, but all of these trials are in very early stages. Scientists are studying remdesivir, an experimental anti-Ebola drug, while blood plasma treatments are also being studied. Hydroxychloroquine, touted as a potential “game changer” by US President Donald Trump, has been shown not to work on very ill patients.

“The drugs they have chosen are the best candidates,” said Keith Neal, professor emeritus in epidemiology of infectious diseases at the University of Nottingham. The problem, he says, was “the piecemeal approach” to testing them.

Remdesivir, one of the drugs tested as a Covid-19 treatment.

“We have to do randomized controlled trials. It’s ridiculous that it’s only recently that we’ve been able to get this off the ground, ”said Neal, who reviews the tests for inclusion in medical journals, at CNN. “The papers I’m going to look at – I just reject them on the grounds that they are not properly made. “

Now, these more comprehensive trials have started, and if any of these drugs work for Covid-19, the signs should appear “within a few weeks,” said Neal. The first may have already happened; the United States Food and Drug Administration has told CNN that it is in talks to make remdesivir available to patients after positive signs that may speed healing of the coronavirus.

The ripple effects of a successful treatment would be widely felt; if a drug can reduce the average time a patient spends in intensive care by a few days, it would free up hospital capacity and could therefore greatly increase the willingness of governments to open up society.

But the effectiveness of a treatment would depend on which one works – remdesivir is not in large quantities internationally and increasing production would be problematic.

Most importantly, no treatment will prevent infections from occurring in society – which means that the coronavirus will be easier to manage and the pandemic will subside, but the disease may be present for many years in the future.

What life is like without a vaccine

If a vaccine cannot be produced, life will not remain as it is now. This may not return to normal quickly.

“The foreclosure is not economically viable and perhaps not politically viable,” says Neal. “So we need other things to control it. “

This means that, as countries begin to emerge from their paralyzes, experts will push governments to implement a new way of living and interacting to buy world time in the months, years or decades up that Covid-19 can be eliminated by a vaccine.

“It is absolutely essential to work to be ready for Covid,” said Nabarro. He calls for a new “social contract” in which the citizens of each country, while starting to live normally, take personal responsibility for isolating themselves if they show symptoms or come into contact with a possible case of Covid-19 .

Social distancing and blockages could be reintroduced until a vaccine is found.

This means that the culture of ignoring coughs or mild cold symptoms and sneaking into work should be finished. Experts also predict a permanent change in attitudes towards working at a distance, working from home, at least on certain days, becoming a standard lifestyle for white-collar workers. Companies are expected to change their rotation so that offices are never unnecessarily full.

“This (must) become a way of behaving that we all attribute to personal responsibility … to treat those who are isolated as heroes rather than outcasts,” says Nabarro. “A collective pact for survival and well-being in the face of the threat of the virus.

“It will be difficult to do in poor countries,” he adds, so finding ways to support developing countries will become “particularly politically sensitive, but also very important.” He cites tightly packed refugee and migrant camps as areas of particular concern.

In the short term, Nabarro says an extensive test and contact finder program should be implemented to allow life to work alongside Covid-19 – a program that overshadows any such program ever in place to fight an epidemic, and that remains for some time in major countries like the United States and the United Kingdom.

“It will be absolutely essential to have a public health system in place that includes contact tracing, workplace diagnosis, surveillance of syndromic surveillance, early communication on the need to restore social distancing”, add Hotez. “It is doable, but it is complicated and we have never done it before. “

America & # 39; s & # 39; new normal & # 39; will be anything but ordinary

These systems could allow the return of certain social interactions. “If there is minimal transmission, it may indeed be possible to open things up for sporting events” and other large gatherings, says Hotez – but such a decision would not be permanent and would be continually evaluated by governments and public health organizations.

This means that the Premier League, the NFL and other mass events could continue their program as long as the athletes are regularly tested and welcome fans for weeks at a time – perhaps separated in the stands – before closing quickly stages if the threat goes up.

“Bars and pubs are probably the last on the list as well because they are overcrowded,” suggests Neal. “They could reopen as restaurants, with social distancing. Some European countries have indicated that they will begin to allow restaurants to serve customers at considerably reduced capacity.

Restrictions are more likely to return during the winter, Hotez suggesting that spikes in Covid-19 could occur every winter until a vaccine is introduced.

And the bottlenecks, many of which are being gradually lifted, could come back at any time. “From time to time there will be epidemics, travel will be limited – and this may apply to parts of a country, or even an entire country,” said Nabarro.

The more time passes, the more imposing becomes the much debated perspective collective immunity – reached when the majority of a given population, about 70% to 90%, becomes immune to an infectious disease. “It limits the spread to some extent,” says Offit – “although population immunity caused by natural infection is not the best way to provide population immunity. The best way is with a vaccine. “

Measles is “the perfect example,” says Offit – before the vaccines spread, “2 to 3 million people will get measles every year, and so will it.” In other words, the number of deaths and suffering caused by Covid-19 would be enormous even if a large part of the population is not susceptible.

All of these predictions are tempered by the general belief that a vaccine will eventually be developed. “I think there will be a vaccine – there is a lot of money, there is a lot of interest and the goal is clear,” said Offit.

But if previous epidemics have proven anything, it’s that vaccine hunts are unpredictable. “I don’t think a vaccine was developed quickly,” said Offit. “I would be really surprised if we had something in 18 months. “

LEAVE A REPLY

Please enter your comment!
Please enter your name here