Explained: Peak of India’s Covid-19 second wave in sight, but end may still be far away

All indications from the coronavirus numbers in India in the last two weeks suggest that the second wave of infections may already have reached a peak, or will peak in the next few days. The end of the second wave may still be a long-distance away, though.

After reaching a high of 4.14 lakh last Thursday, the daily count of cases has dropped significantly in the last week. This is not happening for the first time, though. After crossing the four-lakh mark for the first time on April 30, the case count had gone down for a few days, before jumping again. But the new thing is that the seven-day average of the case count, which adjusts for daily fluctuations, has begun to decline for the first time during the second wave. The seven-day average peaked at 3.91 lakh on May 8 and has begun to decline after that. On Wednesday, this average had slipped to 3.75 lakh. (See graph below)

A five-day decline in the average case count may not be a strong enough indicator in itself to establish a trend, but there also are other signals that are pointing in the same direction.

A Decline in the Surge States

Maharashtra, which at one point was contributing more than 60% of daily cases, certainly seems to be in a declining phase now. It’s been more than three weeks now since the state reported its single-day highest case count of 68,631. After hovering in the 60,000s and 50,000s for two weeks, the state’s daily case count has dropped to the 40,000s now.

The decline in Maharashtra is likely to have the biggest impact on the national curve. For a few days, an unexpected jump in the cases reported by Karnataka and Kerala more than compensated for the decline in Maharashtra, but the chances of these two states sustaining their threat over a long period are showing signs of waning. The continued decline in Maharashtra could make Karnataka and Kerala the highest contributors of cases, but it appears unlikely now that either of them would contribute as many Maharashtra has done.

The biggest glimmer of hope is coming from Uttar Pradesh. The state has the potential to report even more cases than Maharashtra. And at one time, Uttar Pradesh indeed seemed headed in that direction when its daily case count rapidly progressed to 35,000 at the end of April. However, for more than one week, now, the state’s daily tally has remained well below 30,000 and is showing signs of declining.

Like Maharashtra, Delhi also seems to have reached a peak and appears to be in a declining phase. The city-state had been reporting cases in the high 20,000s for some time, but this has now dropped to less than 12,000 a day.

The decline in Maharashtra, Delhi, Uttar Pradesh, and also Chhattisgarh, is not being compensated by any major rise in other states, though Tamil Nadu, Andhra Pradesh, and West Bengal could give anxious moments. The case count in Tamil Nadu has crossed 30,000 while Andhra Pradesh and West Bengal have breached the 20,000 marks. All these states are in the ascendant phase right now.

Active Cases

For the first time in two months, the number of active cases saw a drop this Monday and Tuesday. Until the end of April, the active cases were rising by almost a lakh every day. Through May, this daily increase has been reduced substantially. In the last few days, the active cases have increased by less than 10,000 a day.

A large part of this has to do with the fact that the number of daily recoveries has now caught up with the daily case count. The recoveries tail the case count by two weeks.

Now that the daily case count has remained more or less stable for the last two weeks, the number of recoveries has reached the same level as the case count. The runaway increase in active cases has been halted.

Current trends indicate that active cases could peak well under the 40-lakh mark. As of Wednesday, there were 37.1 lakh active cases in the country.

Positivity Rate

The defining characteristic of the second wave was the high positivity rate. Out of those being tested, many more people were turning out to be positive as compared to the first wave. India’s overall positivity rate remained between 5% and 6% during the first wave, although there were small phases where it rose to more than 12 percent. In the second phase, however, the positivity rate has exceeded 20%. In some states, it even went past 40%.

Positivity rate is a measure of the disease prevalence in the population. If a very large number of people are infected, many more would be detected positive when tested. A higher positivity rate could be an indicator of faster transmission of the virus, either because the new mutants are faster transmitting, or because physical distancing rules have been abandoned, allowing the virus to spread freely.

The positivity rate had kept on rising throughout the month of April and also the first week of May, but now there are signs that it might be stabilizing. In fact, the growth curve of the positivity rate looks very similar to that of the daily case count. (See graph).

However, the observed stability in the positivity rate could also be a result of India’s testing capacity has reached its limit. The country’s testing numbers have hardly been able to keep pace with the increasing infection. While the daily case count increased five-fold in April, testing numbers grew only 1.8 times. As a result, testing as a tool to control the spread of the disease — by forcing the known infected cases into isolation — was never very effective during the second wave.

Death Count

There has been a tenfold rise in the daily count of deaths in the last 45 days. But as the case count has stabilized in the last two weeks, a further rise in the number of deaths is getting arrested. But since it is a lagging indicator, there is a possibility that the deaths could still go on rising for a few days before coming down. As of now, about 4,000 deaths are being reported every day.

Not The End Yet

Although there are hopeful signs, an end to the second wave appears a long-distance away. It had taken five months for the cases to come down from a high of 98,000 a day during the first wave, to about 10,000 a day. This time, India would be starting at a much higher peak. That would mean that the downward journey of the second wave could be that much longer.

Also, unlike the first wave, the decline has not commenced immediately after reaching the peak. The daily count is moving up and down so that we are not even sure whether cases in India have reached a peak. If the curve in Maharashtra, which has closely mirrored that of India for most of this pandemic, is any indication, there is likely to be a prolonged plateau, and then slide down could be slow and not steady. That would mean that India could be reporting a very large number of cases, two to three lakhs a day, for several weeks to come.

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Source: indianexpress