As Europe battles a second wave, Professor Sunetra Gupta, a proponent of herd immunity, explained how things can unfold in the coming days.
Large part of Europe is facing a new wave of infection. (Photo Source: AP)
The United States has reportedly surpassed 10 million coronavirus infections and Europe is facing a new wave of infection forcing the government to implement the second lockdown in a large part of the continent. But overall numbers in India are coming down. No one fully knows the reason. As Europe battles a second wave, Professor Sunetra Gupta, a proponent of herd immunity, spoke to The Indian Express and explained how things can unfold in the coming days while considering factors like heard immunity and cases of reinfection.
Professor Sunetra Gupta, who is a professor of theoretical epidemiology at the University of Oxford, explained that a new pathogen can cause devastation as nobody has any immunity. “But the relationship with the pathogen changes as soon as people start to develop immunity. But it must be noted that immunity typically means that the risk will be very low.”
She explained with the example of Zika virus that hit Brazil in early 2015. “Cases of microcephaly increased sharply during that period and now most people have developed an immunity. This only means that Zika risk is low and not that it has disappeared.”
Describing the scenario for most coronaviruses, she used the analogy of a cistern. Comparing the loss of immunity to the leaky system, she said that the level of immunity stays the same even if there is a lot of water coming in or more water draining out.
What if someone asks that isn’t the water flowing in are new infections? To this, the professor said that typically, those will be reinfections. She confidently said that if the behaviour of SARS-CoV-2 is just like other coronaviruses, the risk of disease and death from reinfections won’t be the same.
Commenting on the importance of herd immunity and antibodies, the professor said that antibodies are just a part of bigger the whole system that we recruit to fight the COVID-19. “As antibodies wane, this won’t tell the exact proportion of the population that has been exposed to the virus.
“Antibodies simply tell that you were recently exposed to the virus. But they do not tell anything about what is going on with the immune response. So it won’t be right to say that protective immunity decays if antibodies are perishing.”
It is a complex situation as previous exposure to other coronaviruses also gives you some immunity to this new virus, she said.
The professor said that it would be unfair to compare the herd immunity of Sweden with Nordic neighbours. “It is also not just to judge it on the number of deaths of during the peak period. A more fair comparison would be Sweden and the UK as the level of deaths was similar.”
In terms of economic losses, it would be a very flawed argument to say that ‘Sweden did just as badly as we did.’
According to what she picked from speaking to netizens of Sweden, they aimed to have something sustainable.
Talking about the strategy of New Zealand which imposed stringent restrictions to curb the outbreak of the coronavirus, she said “it wasn’t sustainable.” The professor said that she was astonished to see that people had a monocular vision on COVID-19 and stopping deaths from it without considering the huge costs of lockdown and it could force millions of people into starvation.
She praised Sweden for handling the pandemic as it decided not to go into complete lockdown but at the same time worked on measures to protect the most vulnerable people. She emphasized that shutting down the economy in any country will cause more harm as it will excessively harm the young and the poor.
She’s of the view that many parts of India have clearly achieved herd immunity as cases of infections are falling naturally. The professor said that this tells us that seroprevalence studies cannot tell the exact proportion of the population that has been exposed, and when.
Talking about the studies in India that state 60-70 per cent antibodies in particular localities, she said that in those areas people were recently exposed and it has overshot the level required for herd immunity. She added that not only do antibodies decay but now it is also known that not everybody makes antibodies.
She said that herd immunity in India will happen in different phases because it is a very large country. “But it will happen for sure. I imagine, though I have not studied all the data carefully, that most part of Maharashtra must have developed herd immunity by now… But there must be other areas where immunity has not progressed that much.”
Commenting on the data that suggests around 10 per cent of Indians who died are of the age group 26-44, she said that it needs to be studied carefully. “Data of several countries clearly states that the population lying in this age bracket have very low risk. Even in the case of elder people, those who died had some form of comorbidity. This may vary from region to region, but elderly people who are fit and healthy have fewer chances of dying.”
But younger people also need to follow the norms of social distancing to reduce exposure, she added.