The point at which India can claim to have achieved herd immunity against COVID-19 is “far away” for the country’s population. This is according to Rajesh Bhushan, an official at the Union Ministry of Health and Family Welfare. He has claimed that the only way India can achieve a level of immunity across the population sufficient to truly contain the COVID-19 is through vaccination campaigns.
While such a vaccination campaign is a monumental task — one that may seem daunting to the point of impossibility — such a task succeeding is not unprecedented in India. The elimination of polio is perhaps one of India’s most remarkable medical successes.
For a long time India was deemed to be one of the most difficult countries to achieve eradication owing to its vast population and geographical diversity. Despite this, a prolonged grassroots vaccination campaign supported by both boots on the ground across India’s healthcare workforce and accredited social health activists (ASHAs), as well as both political and media figures allowed a successful campaign. This coordinated and widely-lauded effort eventually rid India of polio entirely.
Union Health Minister Dr Harsh Vardhan has even invoked India’s success in tackling polio as cause for optimism in India’s fight against COVID-19 (the disease caused by the novel coronavirus). Speaking of India’s collaboration with the World Health Organization (WHO), he noted “time and again the Government of India and WHO together have shown our ability, competence and prowess to the whole world. With our combined meticulous work, done with full sincerity and dedication, we were able to get rid of polio. Today I would like to remind you of your potential and ability, and the big things we can do together…with your joint efforts we can defeat the coronavirus and save lives.”
There are two ways immunity can spread throughout the population, achieving a state known as herd immunity in which a sizable enough portion of the population is immune, reducing the risk of spread to those who have not yet been infected. These methods of achieving herd immunity are through infection and recovery or through vaccination.
The ever-shifting and rapidly changing situation regarding COVID-19 has seen disease experts often split on their opinions of the best course of action. Professor K. Srinath Reddy warned The Hindu of the potential death toll resulting from herd immunity strategies. “The herd immunity idea might prove to be dangerous as it carries the risk of high fatality,” he said in a videoconference on May 7th. “It is better to focus on herd protection by emphasising more on disease containment and protection of vulnerable groups.”
Others, such as Dr Jayaprakash Muliyil, former principal of the Christian Medical College in Vellore and chairman of the Scientific Advisory Committee of the National Institute of Epidemiology, have taken a far more pessimistic outlook. Dr Muliyil (who participated in the Health Issues India co-produced PandemiCast) believes that all efforts to contain the virus have failed — as evidenced by the now considerable rate of infection across the country — and that it is simply a case of achieving herd immunity as fast as possible. This, Dr Muliyil believes, will have less impact in India due to its comparatively younger population.
The numbers behind the potential death toll of herd immunity were previously calculated by Health Issues India
“Reducing the concept down to numbers, the predicted mortality rate of coronavirus was originally two percent — a number then revised to 3.4 percent in early March by the World Health Organization (WHO). Figures for the development of herd immunity vary, though typically range from sixty to seventy percent. The Hindustan Times gives the figure as 65 percent.
“Therefore, of India’s population of 1.377 billion, a total of 895,050,000 would need to be infected. The mortality rate of 3.4 applied to the infected population would therefore translate to 30,431,700 deaths from the virus (not inclusive of any further deaths after herd immunity is achieved, or a higher death rate in India due to health systems likely being overwhelmed).
“India’s current death rate is around 7.5 per 1,000 population — or roughly 10,327,500 per year. The total toll of coronavirus before herd immunity is even achieved is therefore the cumulative deaths of every single potential cause of mortality — heart disease, cancer, infectious diseases, pollution — for three years in a row. All of this for the achievement of a concept which could leave 35 percent of the population still prone to infection.”
The fact that herd immunity could incur a significant death toll is not lost on health officials in India. “For a large country like India, herd immunity cannot be a strategic choice or a strategic option… It will come at too high a cost and can be done only through immunisations via vaccination,” said Bhushan, during a briefing on Thursday. “India is in touch with global multilateral organisations such as GAVI, CEPI [Coalition for Epidemic Preparedness Innovations], WHO etc. to see how it can be made accessible for people in India.”
More than twenty vaccines are currently going through human trials, with two of these being tested domestically within India. Production and successful testing of the vaccine will be vital in addressing the ongoing pandemic. However, there are a number of factors that could cause issues even if the vaccine is approved. Delays are to be expected. A rushed and ineffective vaccine could not only prove to have little impact, but diminish confidence in any future vaccines which could in turn reduce the efficacy of vaccination efforts even with an effective vaccine.
Furthermore, ensuring access to the vaccine must be of the utmost importance once it is developed. As a highly infectious disease the virus will still pass among the population if only a partial segment of the population are granted access. Likewise if only some countries are receiving the vaccine in significant quantities, international travel could once again allow the virus to resurge.
Herd immunity — particularly in a country with a population as vast as India’s — can only be achieved without devastating loss of life through vaccination campaigns. The production of an effective vaccine is only the first step in this. Ensuring equal access to the vaccine will be the determining factor in whether we truly put a stop to COVID-19.