Number Theory| Covid-19: Why India is on the right track now
India’s Covid-19 numbers have taken a turn for the better. The rate of new infections being reported across the country is at the lowest level in five months, shows data analysed by HT. This is the first time a drop of this magnitude and consistency has been recorded in the Covid-19 trajectory in the country.
All data points to this being the best situation the outbreak has been in five months. A look at how numbers show India is swinging the battle against the disease.
1. India’s daily case trajectory at lowest in 5 months
On Monday, India recorded 22,022 new Covid-19 cases, according to HT’s Covid-19 dashboard. This is the lowest number of new infections reported across the country since July 2, when the country saw 21,853 daily cases. The seven-day average of daily cases, also referred to as the case trajectory of a region, touched 93,617 on September 16, the highest recorded till date. As of Monday, this number stands at 28,827 — down 69% from the peak. The last time it was at this level was on July 15, or five months ago, when it was 28,594.
One of the best signs, however, is that there have been little fluctuations in the drop in the trajectory. The seven-day average has seen a near-steady decline since the mid-September peak (barring a weeklong fluctuation seen in the second half of November, caused largely by rising cases in Delhi, West Bengal and Rajasthan).
2. For the first time, Covid situation is under control in all of India’s hot spot states
Even after India’s new cases hit the mid-September peak, there were some regions that were still reporting rising numbers – notably Delhi, Kerala, West Bengal and Rajasthan. Delhi’s third wave, for instance, was so strong that it caused a momentary spike in the overall numbers across the country in November. However, in the past fortnight, even that has been brought under control.
As a result, for the first time since the outbreak gripped the entire country, numbers are receding in every major hot spot region in the country. In India’s worst-hit state, Maharashtra, the seven-day average of daily cases has dropped nearly 82% from the peak of 22,149 seen on September 17. In Karnataka, this has dropped 87% from the peak; in Andhra Pradesh it is down 95%; it is 82% down in Tamil Nadu; and Kerala has seen a 47% slump from the peak witnessed in the state. Delhi, which has seen the latest peak (7,341 cases a day for the week ending November 14), has also witnessed an impressive 71% drop from its peak.
3. Testing right: Positivity rate touches lowest ever
On Monday, 2.2% of samples tested across India came back positive – the lowest single-day positivity rate reported since April 25 (also 2.2%). The average rate of samples testing positive for Covid-19 across the country has dropped from 9.3% for the week ending September 22 to 3% for the week ending June 17, another trend that is suggestive of a contracting outbreak. In the nearly eight months since the Indian Council of Medical Research (ICMR) had been releasing data on Covid-19 testing in the country, this is the lowest that the average positivity rate has ever touched in India.
A dropping positivity rate, coupled with falling new cases, suggests that the testing strategy against the virus is paying dividends. India’s rate of testing (seven-day average of daily tests) has been hovering very close to peak levels – it has remained around the million mark (963,800 samples were tested every day in the preceding week) over the past three months.
4. The secret to Delhi’s remarkable turnaround
Delhi was one of the key regions that defied the larger trend when India’s first Covid-19 wave started receding for the first time. While cases were dropping across the country in early October, the Capital was seeing the start of the third wave. This wave peaked in mid-November and has seen a remarkable turnaround since. The reduction in new infections has come hand-in-hand with a drop in the positivity rate and a significant improvement in testing.
On December 15, for instance, Delhi tested 85,105 samples for Covid-19, of which 42,056 were tested using the more accurate Reverse Tanscription-Polymerase Chain Reaction (RT-PCR) method. Both these figures were single-day records for Delhi. But despite a record number of tests, the single-day positivity rate was only 1.9% – only once (April 6) has Delhi ever reported a fewer proportion of samples testing positive. The average positivity rate on Tuesday stood at 2.7% – the lowest ever recorded. The average positivity rate should consistently drop to 5% or below if testing is adequate and is keeping the outbreak in control, according to the World Health Organization (WHO). In Delhi, this has presently been below the threshold for nine days in a row.