Covid fourth wave in Delhi? Here's why 11.64 percent positivity rate is worrisome

The coronavirus pandemic has started raising its ugly head in Delhi yet again. The city has been reporting over 10 percent of Covid positivity rate for several days now. The national capital on Wednesday reported 2,073 fresh cases, which is a whopping 37 percent increase compared to the Tuesday numbers. However, the more worrisome figure was the daily positivity rate -- 11.64 percent. 

The last time the positivity rate was at this level was on January 24. The positivity rate at that time was 11.79 percent. There were fears about a fourth COVID wave then, but low levels of hospitalizations meant the surge wasn't deadly as the second wave. The city is facing the same danger now. 

With Wednesday's numbers, the coronavirus tally in Delhi reached 19,60,172. With 5 deaths, the official death toll reached 26,321. 

What is the Covid positivity rate? Why is significant?

The daily positivity rate is the percentage of people testing positive every day. On Wednesday, 17,815 people were tested for the virus out of which 2,073 tested positive. The percentage of people turning positive is the daily positivity rate. 

The daily positivity rate is one of the most prominent indicators of the prevalence of a virus in the population. During the second wave, thousands of people were being tested for the coronavirus every day and the positivity rate reached 30 percent. 

If the positivity rate declines to less than 5 percent, the pandemic is believed to be under control. Between 5-10 percent, it is considered to be a surge. The positivity rate climbing past the 10 percent mark is a cause of concern. It could mean the city is heading for a new wave. 

Is it a fourth wave? It is too early to tell. For it to be called a new wave, the positivity rate must remain north of the 10 percent mark for a considerable time. The wave wouldn't be a cause for concern if it doesn't increase the hospitalization rate, which is the percentage of Covid-positive people getting admitted to hospitals. Low hospitalization means the number of people getting seriously ill is less. 

Delhi's positivity rate has risen steadily over the last week. The city recorded 1,506 Covid cases and three fatalities on Tuesday at the rate of 10.69 percent daily positivity. The rate was 11.41 percent a day before. 

Delhi logged 1,263 COVID-19 cases on Sunday with a positivity rate of 9.35 percent. A day before, the city logged 1,333 cases with a positivity rate of 8.39 percent.