“As
countries lie frozen in lockdown and billions of people lose their livelihoods,
public figures are teasing a breakthrough that would mark the end of the
crippling coronavirus pandemic: a vaccine. But there
is another, worst-case possibility: that no vaccine is ever developed. In this
outcome, the public's hopes are repeatedly raised and then dashed, as various
proposed solutions fall before the final hurdle.
“Instead
of wiping out Covid-19, societies may
instead learn to live with it. Cities would slowly open and some freedoms will
be returned, but on a short leash, if experts' recommendations are followed. Testing
and physical tracing will become part of our lives in the short term, but in many
countries, an abrupt instruction to self-isolate could come at any time.
Treatments may be developed -- but outbreaks of the disease could still occur
each year, and the global death toll would continue to tick upwards.
“It's
a path rarely publicly countenanced by politicians, who are speaking optimistically about human
trials already underway to find a vaccine. But the possibility
is taken very seriously by many experts -- because it's happened before.
Several times. ‘There are some viruses that we still do not have vaccines against,’
says Dr. David Nabarro, a professor of global health at Imperial College
London, who also serves as a special envoy to the World Health Organization on
Covid-19. ‘We can't make an absolute assumption that a vaccine will appear at
all, or if it does appear, whether it will pass all the tests of efficacy and
safety. It's absolutely essential that all societies everywhere
get themselves into a position where they are able to defend against the
coronavirus as a constant threat, and to be able to go about social life and
economic activity with the virus in our midst,’ Nabarro tells CNN.
“Most
experts remain confident that a Covid-19 vaccine will eventually be developed;
in part because, unlike previous diseases like HIV and malaria, the coronavirus
does not mutate rapidly. Many, including National Institute of Allergy and
Infectious Diseases director Dr. Anthony Fauci, suggest it could happen in a
year to 18 months. Other figures, like England's Chief Medical Officer Chris
Whitty, have veered towards the more distant end of the spectrum, suggesting that
a year may be too soon.
“But
even if a vaccine is developed, bringing it to fruition in any of those
timeframes would be a feat never achieved before. ‘We've 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, tells CNN. ‘It
doesn't mean it's impossible, but it will be quite a heroic achievement. ‘We
need plan A, and a plan B,’ he says.
When
vaccines don’t work:
“In
1984, the US Secretary of Health and Human Services Margaret Heckler announced
at a press conference in Washington, DC, that scientists had successfully
identified the virus that later became known as HIV -- and predicted that a
preventative vaccine would be ready for testing in two years.
“Nearly
four decades and 32 million deaths later, the world is still waiting for an HIV
vaccine. Instead
of a breakthrough, Heckler's claim was followed by the loss of much of a
generation of gay men and the painful shunning of their community in Western
countries. For many years, a positive diagnosis was not only a death sentence;
it ensured a person would spend their final months abandoned by their
communities, while doctors debated in medical journals whether
HIV patients were even worth saving.
“The
search didn't end in the 1980s. In 1997, President Bill Clinton challenged the
US to come up with a vaccine within a decade. Fourteen years ago,
scientists said we were still about 10 years
away. The difficulties in finding a vaccine began with the very
nature of HIV/AIDS itself. ‘Influenza is able to change itself from one year to
the next so the natural infection or immunization the previous year doesn't
infect you the following year. HIV does that during a single infection,’
explains Paul Offit, a pediatrician and infectious disease specialist who
co-invented the rotavirus vaccine. ‘It continues to mutate in you, so it's like
you're infected with a thousand different HIV strands,’ Offit tells CNN. ‘(And)
while it is mutating, it's also crippling your immune system.’
“HIV
poses very unique difficulties and Covid-19 does not possess its level of
elusiveness, making experts generally more optimistic about finding a vaccine. But
there have been other diseases that have confounded both scientists and the
human body. An effective vaccine for dengue fever, which infects as many
as 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.
“Similarly,
it's been very difficult to develop vaccines for the common rhinoviruses and
adenoviruses -- which, like coronaviruses, can cause cold symptoms. There's
just one vaccine to prevent two strains of adenovirus, and it's not
commercially available. ‘You have high hopes, and then your hopes are dashed,’
says Nabarro, describing the slow and painful process of developing a vaccine. ‘We're
dealing with biological systems, we're not dealing with mechanical systems. It
really depends so much on how the body reacts.’
“Human
trials are already underway at Oxford University in
England for a coronavirus vaccine made from a chimpanzee virus,
and in the US for a different
vaccine, produced by Moderna. However, it is the testing process --
not the development -- that holds up and often scuppers the production of
vaccines, adds Hotez, who worked on a vaccine to protect against SARS. ‘The
hard part is showing you can prove that it works and it's safe.’
Plan
B:
“If
the same fate befalls a Covid-19 vaccine, the virus could remain with us for
many years. But the medical response to HIV/AIDS still provides a framework for
living with a disease we can't stamp out. ‘In HIV, we've been able to make that
a chronic disease with antivirals. We've done what we've always hoped to do
with cancer,’ Offit says. ‘It's not the death sentence it was in the 1980s.’
“The
groundbreaking development of a daily preventative pill -- pre-exposure
prophylaxis, or PrEP -- has since led to hundreds of thousands of
people at risk of contracting HIV being protected from the
disease.
“A
number of treatments are likewise being tested for Covid-19, as scientists hunt
for a Plan B in parallel to the ongoing vaccine trials, but all of those trials
are in very early stages. Scientists are looking at experimental anti-Ebola
drug remdesivir, while blood plasma treatments are also being explored.
Hydroxychloroquine, touted as a potential ‘game changer’
by US President Donald Trump, has been found not to work on very sick
patients. ‘The drugs they've chosen are the best candidates,’ says
Keith Neal, Emeritus Professor in the Epidemiology of Infectious Diseases at
the University of Nottingham. The problem, he says, has been the ‘piecemeal
approach’ to testing them.
“‘We
have to do randomized controlled trials. It's ridiculous that only recently
have we managed to get that off the ground,’ Neal, who reviews such tests for
inclusion in medical journals, tells CNN. ‘The papers that I'm getting to look
at -- I'm just rejecting them on the grounds that they're not properly done.’
“Now
those fuller trials are off the ground, and if one of those drugs works for
Covid-19 the signs should emerge ‘within weeks,’ says Neal. The first may
already have arrived; the US Food and Drug Administration told CNN it is in
talks to make remdesivir available to patients after positive signs it could speed up
recovery from the coronavirus.
“The
knock-on effects of a successful treatment would be felt widely; if a drug can
decrease a patient's average time spent in ICU even by a few days, it would
free up hospital capacity and could therefore greatly increase the willingness
of governments to open up society. But how effective a treatment is would
depend on which one works -- remdesivir is not in high supply internationally
and scaling up its production would cause problems. And crucially, any
treatment won't prevent infections occurring in society -- meaning the
coronavirus would be easier to manage and the pandemic would subside, but the
disease could be with us many years into the future.
What
life without a vaccine looks like:
“If
a vaccine can't be produced, life will not remain as it is now. It just might
not go back to normal quickly. ‘The lockdown is not sustainable
economically, and possibly not politically,’ says Neal. ‘So we need other
things to control it.’ That means that, as countries start to creep out of
their paralyses, experts would push governments to implement an awkward new way
of living and interacting to buy the world time in the months, years or decades
until Covid-19 can be eliminated by a vaccine.
“‘It
is absolutely essential to work on being Covid-ready,’ Nabarro says. He calls
for a new ‘social contract’ in which citizens in every country, while starting
to go about their normal lives, take personal responsibility to self-isolate if
they show symptoms or come into contact with a potential Covid-19 case. It
means the culture of shrugging off a cough or light cold symptoms and trudging
into work should be over.
“Experts also predict a permanent
change in attitudes towards remote working, with working from home, at least on
some days, becoming a standard way of life for white collar employees.
Companies would be expected to shift their routines so that offices are never
full unnecessarily. ‘It (must) become a way of behaving that we all ascribe to
personal responsibility ... treating those who are isolated as heroes rather
than pariahs,’ says Nabarro. ‘A collective pact for survival and well-being in
the face of the threat of the virus. It's going to be difficult to do in poorer
nations,’ he adds, so finding ways to support developing countries will become ‘particularly
politically tricky, but also very important.’ He cites tightly packed refugee
and migrant settlements as areas of especially high concern.
“In
the short term, Nabarro says a vast program of testing and contact tracing
would need to be implemented to allow life to function alongside Covid-19 --
one which dwarfs any such program ever established to fight an outbreak, and
which remains some time away in major countries like the US and the UK.
‘‘‘Absolutely
critical is going to be having a public health system in place that includes
contact tracing, diagnosis in the workplace, monitoring for syndromic
surveillance, early communication on whether we have to re-implement social
distancing,’ adds Hotez. ‘It's doable, but it's complicated and we really
haven't done it before.’
“Those
systems could allow for some social interactions to return. ‘If there's minimal
transmission, it may indeed be possible to open things up for sporting events’
and other large gatherings, says Hotez -- but such a move would not be
permanent and would continually be assessed by governments and public health
bodies. That means the Premier League, NFL and other mass events could go ahead
with their schedules as long as athletes are getting regularly tested, and
welcome in fans for weeks at a time -- perhaps separated within the stands --
before quickly shutting stadiums if the threat rises.
“‘Bars
and pubs are probably last on the list as well, because they are overcrowded,’
suggests Neal. ‘They could reopen as restaurants, with social distancing.’ Some
European countries have signaled they will start allowing restaurants to serve
customers at vastly reduced capacity.
Restrictions
are most likely to come back over the winter, with Hotez suggesting that
Covid-19 peaks could occur every winter until a vaccine is introduced.
“And
lockdowns, many of which are in the process of gradually being lifted, could
return at any moment. ‘From time to time there will be outbreaks, movement will
be restricted -- and that may apply to parts of a country, or it may even apply
to a whole country,’ Nabarro says. The more time passes, the more imposing
becomes the hotly debated prospect of herd immunity -- reached when the
majority of a given population, around 70% to 90%, becomes immune to an
infectious disease. ‘That does to some extent limit spread,’ Offit says – ‘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 vaccines became widespread, ‘every
year 2 to 3 million people would get measles, and that would be true here too.’
In other words, the amount of death and suffering from Covid-19 would be vast
even if a large portion of the population is not susceptible.
“All
of these predictions are tempered by a general belief that a vaccine will,
eventually, be developed. ‘I do think there'll be vaccine -- there's plenty of
money, there's plenty of interest and the target is clear,’ Offit says. But if
previous outbreaks have proven anything, it's that hunts for vaccines are
unpredictable. ‘I don't think any vaccine has been developed quickly,’ Offit
cautions. ‘I'd be really amazed if we had something in 18 months’” (Bob Picheta, CNN).
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