Herd Immunity Won’t Save India from COVID-19

India reported its first case of COVID-19 on Jan. 30. As of 21 May (5.30 p.m.) while the country moves through its an unprecedented national lockdown, a total of 112,358 cases have been confirmed with 3435 deaths, where as 63,624 active cases and 45,299 have recovered. While these figures may seem relatively low compared with hot spots in Europe and North America, they may not be capturing the real picture.

With 0.55 hospital beds per 1,000 people, only 48,000 ventilators, and a population of 1.3 billion, many observers wonder how India can manage a crisis as severe as the coronavirus.

Pursuing herd immunity has been as a possible strategy in poor countries with young populations, such as India. This controversial approach, which was recently discarded by the United Kingdom, relies on a majority of the population (60 percent to 80 percent) gaining immunity or resistance to the virus by becoming infected and then recovering.

While this is a common approach underlying mass vaccination campaigns for diseases like measles which rely on safe and tested vaccines trying it with a deadly, new and untreatable disease is a massive risk.

There are three reasons why herd immunity may not work for India and could also be potentially dangerous leading to increased hospitalizations that overwhelm the health system and eventually cause a high number of deaths.

First, experts don’t know a lot about COVID-19 immunity, especially how long immunity lasts, what kind of protection it offers, and whether re-injection is possible. These are all questions that researchers around the world, including those at the World Health Organization, are still trying to figure out.

In its cruelest form, pursuing herd immunity without a vaccine is a version of survival of the fittest.

Second, herd immunity is being recommended for India on the assumption that since the country has a large young population (more than 80 percent fall below the age of 44), many of these younger adults will not have a severe reaction to COVID-19.

However, this assumption is problematic as scores of young Indian adults have dangerous underlying conditions and risk factors that could lead to severe complications and death if infected with COVID-19.

Nearly 40 percent of Indian adults aged 45-54 and 22 percent of those aged 20-44 have hypertension, nearly 4 percent of adults aged 15-44 years have reported Type 2 diabetes, along with a high rate of unreported cases and 2.1 million people are living with HIV, of whom 83 percent are between 15 and 45 years old. Finally, the prevalence of chronic pulmonary disease and asthma among adults was reported as 4 and 3 percent, respectively, and nearly a third of adults use tobacco.

With such high rates of co morbidities and risk factors among the young population, letting the virus spread for the sake of an experimental strategy of herd immunity could lead to hundreds of thousands of people being hospitalized and requiring intensive care. Furthermore, seeking herd immunity among younger populations would still require shielding older adults (roughly 50 million Indians are over the age of 65) who are at higher risk.

Third, herd immunity cannot be implemented as a lone strategy. It will still have to be supplemented with ramping up health system capacity, increased cooperation between the public and private health sectors, increased testing, shielding high-risk populations, and implementing gradations of social distancing measures, such as mandatory use of face masks and banning large public gatherings and crowded spaces, which are commonplace in urban India.

Relying solely on a herd immunity strategy could also be dangerous as it may lower the risk perception among younger populations, affecting their compliance with much-needed social distancing measures. It could also be viewed as an easy route out of the current lockdown and possibly lead to the easing of the government’s current response measures.

First, the central and state governments will have to implement a nuanced testing strategy that moves from a targeted approach focusing on high-risk individuals toward mass community testing. At the moment, the testing criteria include asymptomatic and symptomatic individuals with a travel history to high-risk areas—but travel as a criterion is irrelevant at this point as the country closed its international borders.

It also includes asymptomatic, symptomatic, and high-risk close contacts of confirmed cases, symptomatic health workers, and hospitalized patients with respiratory illness; this criterion will need to be expanded to move toward mass testing (to catch asymptomatic cases among those who are unaware they might be infected) and repeat testing for health workers (who are constantly at risk of new exposure even if they initially test negative).

The central government will need to swiftly address current bottlenecks that hinder widespread testing, including shortage of rapid testing kits and delay of government approval for domestic test kits, and also incentivize domestic biotech companies to produce kits and private laboratories to conduct testing.