It is a problem. But there is now enough know-how to help prevent it, and manage its
consequences.
The universal use of masks in public places is the single most important intervention to
reduce risks
Looking at the rising curve of new cases in India, it may seem premature to talk about what
the new normal will look like. However, just as it was important early in the pandemic to
look ahead to save lives, it is also important to look ahead now to preserve the social fabric
and the economy. The pendulum of fear has swung from one extreme to another with much
misinformation. So, it is time to review what we do know.
The Sars-CoV-2 infection has taken a huge toll globally, with over 600,000 deaths so far. The
actual number of infections is far greater than the known cases. This is important, because it
has led to many misconceptions about the fatality of the disease. For example, in Delhi,
antibody data, which tells us about the percentage of the population that has been infected
and recovered, points to about two to three million infections. When compared to the
130,000-plus known cases and less than 4,000 deaths, the difference is staggering; fatality is
less than 0.2% by antibody data and around 3% by known cases. It is clear that when
diagnostic testing is done extensively, as is now happening in the United States (US), more
than 99% of diagnosed infections recover uneventfully.
The additional risk of dying of Covid-19 is unlikely to be more than a person’s current one year
risk of death. For example, for a young Indian male, the risk of dying of Covid-19 is not
more than the risk of dying in a road accident this year. For a young Indian woman, it is
comparable to the risk of dying during pregnancy. A 70-year-old elderly Indian male already
has an annual risk of death of 5% or more, to which Covid-19 adds about 1% additional risk.
However, none of this means that the problem is small. Restated in another way, the annual
risk of death is being doubled during the pandemic — the additional risk compressed into a
few months. Also, this risk is transmissible to those around us. The real problems begin when
the disease starts to spread so rapidly that it overwhelms the health care system. Then, deaths
start not only because of Covid-19 but also because of other causes that would normally be
preventable. The focus of the new normal should be to get on with our lives, while observing
reasonable precautions to prevent a catastrophic spread.
At the first semblance of normal life, with schools, universities, and more restaurants and
malls opening, there will be a further rise in Covid-19 cases and, consequently, deaths. This
cannot be helped until we have new effective treatments or vaccines. The universal use of
masks in public spaces will probably be the single-most important intervention to reduce the
risks. We don’t require more debate on airborne transmission. It is quite straightforward.
Large droplets from sneezes and coughs are more likely to transmit infections but settle down
fast from the air. While speaking, we expel very small droplets that are less likely to infect,
but remain in the air longer, creating tangible infection risks in closed, crowded and poorly ventilated
spaces. Wearing a mask reduces the droplets we send out and those that we breathe
in. Comfortable surgical masks, or almost any mask, do a good job of the former, while N95
respirators are required to effectively do the latter. If everyone is wearing a mask, N95 is not
required and people can stay comfortable and protected. This is the simplest strategy to
reduce not only the number of infections, but probably also the severity of infection, since it
seems that a higher amount of virus exposure may lead to higher chances of severe disease.
The other necessary intervention is to restrict indoor crowding and increase fresh air
ventilation. As the summer comes to an end in about a month, it will become possible to
bring in fresh air without compromising the temperature control of air-conditioned buildings.
However, optimal design of indoor spaces is still a problem that requires thought on the part
of architects and engineers, especially for restaurants where masks are not possible. Rapid air
exchange with filtration or decontamination is a viable option where fresh air cannot be
brought in.
The other critical need is to destigmatise Covid-19. None of us know where it is coming
from, but there is no reason for panic beyond rational precautions. Most people can safely
self-isolate and recover at home, preferably without any consternation on the part of
neighbours. Reverse isolation, in which high-risk people are temporarily isolated, is another
option. The large number of infections has a silver lining: When managed well, there will be
a large fraction of recovered people with some immunity. Herd immunity is still some
distance away as a nation, but local immunity may be sufficient to prevent large outbreaks in
such areas. In data collected by others and us, about 20-30% of Delhi and Mumbai residents
seem to be in the recovered category based on antibody presence, although these are not
neutralising antibodies with definite anti-virus action.
A very positive sign is that there have been no proven re-infections in over six months of
global experience, despite poor antibody response and lack of neutralising antibodies in many
people. Better immunity tests will allow immunity passports for those who can safely serve at
the frontline of critical high-risk services. The size of our problem may yet become the size
of our opportunity. It is time, despite the doom and gloom, to start thinking of the new
normal.
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