Dengue cases cross 7,000-mark in Delhi, load likely to ease now

Delhi added over 1,800 dengue cases during the week ending on November 20, taking this year’s tally past the 7,000-mark, according to the weekly report released by the city’s municipal corporations on Monday.

No more fatalities were added to the city’s dengue toll for the year.

The city has reported 7,128 dengue cases so far, and nine deaths, according to weekly data released by the North, South, and East Delhi civic bodies.

The tally of the vector-borne infection is the highest since 2015, when there was a major dengue outbreak in the city, which left 16,000 people sick and at least 60 dead.

To be sure, week-on-week cases have declined from the previous seven days for the first time since the seasonal outbreak of the infection in August. Between November 7 and 13, Delhi added 2,569 dengue cases.

Doctors too confirmed that the caseload at their facilities has eased significantly, a drop they attributed to lower temperatures, which are inconducive for vector breeding.

“I would say there has been a 30 to 50% decline in the number of people who came in with dengue in the last one week. In another week or two, cases of the infection will become sporadic,” said Dr Suranjit Chatterjee, senior consultant of internal medicine at Indraprastha Apollo hospital.

Over 5,500 of the cases this year have been recorded in November alone, according the data. This is highly unusual, said officials, since cases of the mosquito-borne diseases starts increasing in July after the monsoon showers and peak in October. The city usually reports few cases in November.

During the 2015 outbreak for instance, Delhi logged only 841 cases in the first three weeks of November. Similarly, the city added only 338 dengue cases in November last year and 787 in the month in 2019.

Officials said the delay in dengue cases dissipating is because of the delayed monsoon, which arrived over two weeks later than usual, and withdrew late as a result.

“The city received very little rainfall in June but very heavy rain intermittently in September. We were able to control breeding very well initially, but then because of the intermittent, heavy rainfall there was an increase in breeding,” said an official from one of the municipal corporations.

The official added, “The breeding has gone down now. However, adult mosquitoes can survive up to a month and dengue symptoms may set in up to 10 days after an infected mosquito bites. So if the breeding happened in October, the number of cases should go down in another week or so.”

According to another official from the corporation, “There are still some deaths that need to be investigated.” Deaths due to dengue are reviewed by an expert death audit committee and are added to the official toll after confirming dengue as the cause of death and whether the infection was contracted in Delhi.

The number of cases is high this year, likely due to the government notification mandating all hospitals, nursing homes, clinics, and diagnostic centre to report cases of dengue, malaria, and chikungunya. “Only 10% of the cases are backlog; almost 90% cases are fresh,” the first MCD official said.