Millions of people living in India live in densely populated surroundings, with only limited access to clean water, and without the resources to ensure food and other hygiene.
These conditions make people additionally susceptible to being infected with Covid -19 and India has recorded almost 11 million cases of the disease to date – or some 16% of all the cases worldwide. This correlates to the Indian population however, which currently stands at 16% of the global population.
However, researchers have been pointing to an anomaly in the country’s death rate from Covid-19 for some time now. While India has 16% of Covid-19 infections, it only has 10% of Covid-19 deaths.
According to the Financial Times India’s case fatality rate, which is a measure of death in patients with Covid-19, is less than 2% – or one of the lowest in the world. Furthermore, while Covid cases were peaking in November, the number of daily new infections are now dropping rapidly.
Hospitals which were previously overwhelmed have seen sharp falls in admissions, and are now seeing empty beds on Covid wards. “To our relief and surprise, the number of cases have started to come down drastically,” one doctor told the Financial Times.
The number of newly confirmed Covid-19 infections have fallen from a peak of nearly 100,000 new infections a day in mid-September to an average of 13,000-14,000 a day in January. So what is happening in India? Is the virus burning out – is India reaching herd immunity in relation to the coronavirus? And, can living in crowded, densely populated areas with poor sanitation actually confer an advantage in dealing with the Coronavirus?
Social distancing is hugely difficult in cities where millions of people live close together, often sharing water and toilet facilities. Viruses are more likely to spread in these conditions.
Last August, medical research carried out in India’s commercial capital, the packed city of Mumbai with some 6 million inhabitants, found that more than half of the residents of the slums examined in three areas of the city tested positive for antibodies to the coronavirus.
The survey showed that 57% of the people living in these densely populated areas may now be immune to the disease. While initially it was thought that producing antibodies after a Covid-19 infection might not confer immunity, the latest studies are now strongly suggesting that strong, lasting immunity – perhaps lasting decades – can be gained by people infected by the virus.
The Mumbai results come from random testing of some 7,000 people in three of the poorest areas of the cities in early July, carried out by government think-tank Niti Aayog and the Tata Institute of Fundamental Research.
The survey indicates that, as indicated by the WHO, the vast majority of people who got Covid-19 will recover and not need hospitalisation. Many were asymptomatic.
Now, other studies in other cities in India are finding similar results. The Times of India reports that a survey of 28,000 people in the capital of New Delhi showed that more than 50% of people living there could have antibodies to the virus. The city could be headed towards herd immunity and this could be a reason behind the consistent dip in the numbers of confirmed cases, the paper reported.
In November, another Mumbai study suggested that the percentage of people with Covid-19 antibodies might have increased to 75%.
“What we seem to have done is let the virus run its course,” virologist T Jacob John told the Financial Times. “By not flattening the curve in the beginning, India went through the herd immunity threshold and the epidemic seems to be naturally coming down.”
Other experts posit an interesting theory – that the difficult and unhygienic conditions in slums and crowded cities may have actually given those inhabitants an advantage. Being exposed to various pathogens – a diverse range of microbes – from childhood might have given low-income people sturdier immune systems, with a tougher ability to battle viruses like Covid-19.
Indian scientists compared data from 106 countries taking into account variables such as density of population, demography, prevalence of diseases, and quality of sanitation. They found that more people had died of Covid-19 in high income countries. “People in poorer, low income countries seem to have a higher immunological response to the disease compared to high income peers,” Dr Mande, one of the authors of the study, told BBC.
These studies are observational, and other experts argue that India’s young population may also contribute to its low fatality rate, and caution against variant surges. But Dr Randeep Guleria, a member of the government’s Covid-19 task force is cautiously hopeful that “the worst is over”.
“In certain areas, like large cities, we may have come close to achieving a good amount of immunity — if not herd immunity, close to it,” he said.