Pandemic problem: India’s Covid curve is still rising

If India overtook Brazil over the weekend to become the world’s second-ranked country in terms of total Covid-19 infections so far – India became the top-ranked in terms of new infections on August 8 – the main reason for this is poor levels/protocol for testing so far; this has allowed those with infections to remain undetected and go around spreading the disease.

Worse, in case of those that were diagnosed as Covid-infected, India’s health authorities declared that they had been cured without even testing them; once again, this allowed the infection to spread. While WHO guidelines say recovery takes place in 14 days, the average for India is 11 days and it is as low as eight days in Bihar.

As a result of this, positivity levels – fresh infections as a share of fresh tests – rose from 6.5% on June 1 (5-day rolling average) to 10.7 on August 1, before falling a bit to 7.6% on September 5; at their peak, positivity levels in India were 17% on March 23. In the US, while the peak positivity was 22.3% on April 7, this fell to 4.9% on June 1, rose to 7.6% on August 1 and then fell to 5.6% on September 5. In the case of Italy, once the worst in the world, positivity rates had shot up to 13% on April 24 but are now down to 2.1%.

While the number of tests that India has done has shot up, from 40 lakh on June 1 to 4.9 crore on September 5, this is very low compared to other countries, especially when seen relative to the levels of population. On June 1, the US had done 1.9 crore tests and this rose to 9 crore on September 5.

In per capita terms, the comparison is far worse. On June 1, India had done a mere 2.9 tests per thousand persons as compared to 57 for the US; on September 5, India had one 35.4 tests per thousand persons versus 272.7 for the US. The UK had done 223 tests per thousand on September 5 and Germany 147.8 (see graphic)

While data is not available for all countries, India’s testing data becomes even less impressive when you consider that an increasing share of India’s tests are Rapid Antigen Tests (RAT) which have a much lower ability to detect Covid-19 infections as compared to the conventional RT-PCR tests. In a submission to the Delhi High Court on July 27, the Delhi government had said that between June 18-July 21, 19.3% of those tested using RT-PCR were found to be Covid-positive versus just 6.3% in the case of the RAT tests. Interestingly, the sero survey done in August had estimated that 29% of Delhi’s population had at one time or the other been infected with Covid-19.

So, the states/cities that have a high share of RAT tests, like Delhi and Bihar, could well be understating their infection levels as compared to a Tamil Nadu that has virtually no RAT tests. Interestingly, in this context, one of the reasons for Delhi’s infection levels rising over the past few weeks is the fact that the share of RT-PCR tests is rising again.