New infection levels in Italy followed a similar trajectory and started falling after Day 57.

In just the last month, the number of fresh infections showing up per 100 tests in Maharashtra has nearly doubled, from 10.5 on May 3 to 19.6 on June 3; in the case of Delhi, it jumped from 7.2 to 18.9, while for the country as a whole, it rose from 3.1 to 6.8.

Not surprising then that at last week’s health ministry briefing, ICMR scientist Dr Nivedita Gupta (division of epidemiology and communicable diseases) said India’s peak rate — the rate after which daily new infections start falling — was quite far away.

To understand this (see graph) note that the number of new infections per 100 new tests rose from 0.4 on Day 1 in the UK (from the time the country started doing 1,000 daily tests) to a high of 52.8 on Day 39 and then continued to fall to as low as 3.9 on Day 82.

New infection levels in Italy followed a similar trajectory and started falling after Day 57. Similarly, in the US, the ‘positivity rate’ — the number of fresh infections per 100 tests — rose from 6.3 on Day 1 to 22.2 on Day 24 and then fell to 5.4 on Day 80.

If things are bad in states like Delhi and Maharashtra that account for, respectively, 11% and 20% of India’s infections, they are even worse in some others like Tamil Nadu, which accounts for 12% of infections and where new infections per 100 tests rose from 1 on April 19 to as much as 8.8 on June 3.

The one state where they have fallen is West Bengal, from 6.6 to 3.5 in the same period. However, there seems to be a data problem here, possibly due to the fact that the state’s testing remains quite low at 2,236 tests per million people compared with 3,929 for Maharashtra, 6,609 for Tamil Nadu and 11,073 for Delhi.

Even Delhi and Maharashtra, though, need to step up their testing significantly. While Delhi accounts for 10.7% of India’s infections, it accounts for just 5.6% of tests; in the case of Maharashtra, the numbers are worse at 34.8% and 11.8%, respectively.

Indeed, the fact that Indian testing levels are so low compared with those in developed nations – along with a rising positivity rate – makes it clear that India will keep discovering more infected persons as it increases its levels of testing. As it happens, the Delhi government is effectively keeping testing low by show-causing private laboratories for testing asymptomatic people.

The rising death rates also tell the same story. The death rate in Delhi increased to 2.5% on June 3, it was only 1.6% a month ago. Though death rates in Mumbai have fallen during the same period, for Kolkata and Ahmedabad, they have increased. Ahmedabad’s death rate increased from 5.2 on May 3 to 7 on June 3. Kolkata’s nearly doubled to 9.7. A high death rate may mean severe cases are rising, but it also indicates that there may be more infections than are believed.

For instance, early in the corona fight, Gujarat’s high death rates led to more cases being discovered in the state. On April 4, for instance, Gujarat reported 10 new cases, a total of 105 cases and a death rate of 9.5%. In another two weeks, as testing picked (from 4,224 on April, a total of 26,102 people were tested by April 18), Gujarat’s total cases rose to 1,272 on April 18 and the death rate fell to a more believable 3.8%.