Kejriwal claims third Covid-19 wave in Delhi, but experts say it is a continuation of first wave

Delhi Chief Minister Arvind Kejriwal has said Delhi was currently facing the third wave of Covid-19 cases. Without dates and figures, Kejriwal said in the first phase the highest number of cases were reported, then again on September 17, there was a surge.

However, public health experts have countered it stating that Delhi is still going through the first wave. They said Covid-19 case positivity never went down considerably for the current spike to be called a second or third wave.

Sticking to the description of the third wave, Delhi health minister Satyendar Jain said the steep rise in the number of cases can be considered to be the third wave. On Sunday, Delhi recorded 7,745 Covid-19 cases, which was the highest single-day spike and there were 77 deaths. In November, on an average, there have been more than 60 deaths every day.

Epidemiologists and virologists disagree with the government’s attempt to call it a third wave of Coronavirus cases. All of them think it’s the first wave that has been continuing. “This is just a spike in the number of cases in Delhi. It’s not a wave. We have always been on the ascending limb of the epidemic. We are still going up and the numbers of cases have not come down. There were only small periods where we have had lesser number of cases. These are spikes that come and go,” underscored Dr Lalit Kant, former head, epidemiology and communicable diseases, Indian Council of Medical Research.

A new wave can be defined when after a definitive dip (where the cases almost touch the baseline and remain at the baseline for a while), the cases surge. This is what has happened in Europe. That is not what has happened here. “It is the same wave that is continuing in Delhi,” said Dr Sanjay Rai, Professor at Centre for Community Medicine, All India Institute of Medical Sciences (AIIMS).

Kant added that people can term it anything, “but that doesn’t mean it is a wave or a peak”.

“What we are seeing are just tips of the iceberg over a period of time. We do not have the full picture as there is no comprehensive surveillance in place, no contact tracing for every case or isolation and testing of everyone,” echoed Dr Oommen John, senior research fellow at The George Institute of Global Health. “For comparison, we have to look at countries such as Vietnam and Taiwan, who kept a vigil all through,” he said.

These surges in the number of cases are largely a function of people who are extremely sick, said John. “The surge is so high that the number of people needing institutional care and ICU beds have increased. This is a easily transmitted disease, but unless we have a proper public health response, we can’t measure it,” said John.

He added that a large number of people who have contracted the virus are asymptomatic and therefore they have not necessarily tested. “They are happily going around. I would think of what is happening now as the continuation of what was going on earlier with temporary dips in between,” said John.

To explain it, we must go back to June. During the last week of June when there were around 4,000 Covid-19 cases, the positivity rate was more than 20%. “At the same time two sero-surveys were done in Delhi and they found that in the first sero-survey, the positivity was around 23%. The next survey found that the Covid-19 positivity was around 29%. This means that around 12 lakh persons in a month were infected, translating to 60,000 infections per day. The sero-surveillance report is the most robust evidence that we have of infections in Delhi,” explained Rai.

The number of cases detected is based on the number of tests done. In June, the average number of tests done were 20,000 and now around 50,000 tests are being done. On Sunday, the positivity rate was around 15%.

“In August-September, there was a slight dip, but as we increased the number of cases, the positive numbers have also increased. Currently, there is a slight increase if you compare with September, but if you compare the positivity rate with that of June, we are at the same level. I cannot say it is either the second or the third wave. The current numbers are a part of the first wave itself as the first wave is not over yet,” remarked Rai.

The second criterion is that during the second wave the cases should be from the same population. In Delhi, it is not from the same population. “Earlier, in May-June, the majority of the cases were from central Delhi, north Delhi and south-east Delhi. The sero-surveillance also suggested the same. Now, cases are from west Delhi, old Delhi, south-east Delhi,” observed Rai.

Reiterating Rai, John said in the absence of a strong disease surveillance system, we don’t know the true disease transmission rate. Therefore, what we see now is a factor of transmission and a proximity to do tests.

It will take at least three months for the number of Covid-19 cases to fall. “The higher number of cases is not because of the increased testing; it is because there is increased transmission in the Capital. To cite an example, if milk has 2% fat, whether you take 200 ml or 2 litres, it will still show 2% fat. So, even if you test more, the positivity rate should remain the same. So, with increased testing if there are more positives, it means that there are more cases. It means there is transmission and there are a large number of cases of which they are able to pick up only a small percentage,” asserted Kant.

Chances are that they opened too soon, said Kant, and they opened too much. “The Delhi government gave the impression that they have enough beds, and that they would be able to take care of anyone who got infected,” maintained Kant.

Governments should look at epidemiological data and then make decisions on whether to open up. “Here the governments decide on ‘unlocking’ dates first. We are in 2020. Such decisions should be made while looking at epidemiological data, but here it is driven by dates.

Once markets are opened, it takes upto six weeks for Coronavirus cases to build up. “That’s what has happened. Unless the government takes measures to decrease interactions between people, the number of cases will not drop. People are not taking precautions, aren’t wearing masks. The government needs money, people need money at the expense of people falling ill. The economic reasons are over-riding everything else,” remarked Kant.

The situation in Delhi is alarming because people have stopped being on guard in Delhi. “Most people roam around without wearing masks and they think that coronavirus is a thing that will happen to someone else. They believe that it will not happen to them. Respiratory viruses have a propensity to worsen during winter and air population significantly increases the risk for Covid-19,” contended John.