COVID-19: India is testing adequately, even slightly better than Korea (!)

The Indian response to the COVID-19 emergency is being led by the Ministry of Health and Family Welfare.

India’s efforts to contain the COVID-19 pandemic have been quicker, earlier, and more far-reaching than most other countries. However, sections of media and public have repeatedly raised concerns that India is not testing adequate number of people.

These concerns are based primarily on two fallacies. We look at them one by one.

Fallacy 1: The total number of tests conducted by India is inadequate

This fallacy is derived from the fact that, while India has conducted more than 25,000 tests by March 25, many other countries have conducted many times more [1].

Almost everybody would agree that comparing the absolute number of tests does not make sense, given the vastly different scenarios faced by each of the countries.

However, the counter argument to this is that per capita testing in India is even lesser, which brings us to the second, more subtle and more popular fallacy.

Fallacy 2: The number of tests per capita conducted by India is extremely inadequate

This fallacy is based on comparison between per capita testing in India and that of other countries. Recent data for some of the countries is given below [1]:

To a cursory look, the above data seems to verify that India is falling alarmingly behind other nations in testing its citizens.

However, to motivate the discovery of fallacy in this argument, consider this:

During the Ebola epidemic, countries in West Africa tested more than 5000 people per million, while it was 0 tests per million people in India. Did this make India alarmingly under-tested for Ebola? No, isn’t it? Why? Because there was not even a single case of Ebola infection in India. Suppose that there were a few hundred cases of Ebola in India. How much testing would be justified? 100 million people? 10 million? 100 thousand? 10 thousand?

It is clear that the number of tests per capita is as meaningless a comparison metric, as is the total number of tests. Just because India has 1.36 billion people, it doesn’t mean that a large fraction need to be tested for all serious diseases.

This is because the biggest factor determining the amount of testing needed, is the penetration of infection in the population, and not the size of the population itself.

Therefore, for a testing program to be successful, the ratio of tests conducted to the number of positive results should be large. In other words, the number of additional precautionary tests conducted per infected individual should be large. The number of tests conducted per capita is a misleading metric.

Let us look at how India fares in this respect [1]:

It is clear that India is performing remarkably great so far, and its testing program is absolutely adequate, with a greater multiple of precautionary testing than even South Korea, which has been recognized worldwide as an exemplary model for large scale testing. Indeed, India’s precautionary testing rate is one of the highest in the world.

References

Awaiting death 🙂