With the death of an 11-year-old girl on Wednesday, the official dengue deaths in the Capital this year rose to three and the number of cases crossed 1,000.
The Municipal Council of Delhi has recorded 1,019 cases so far but data from private hospitals show the number could be five times higher.
The reason for the discrepancy is that the MCD insists on the expensive IgM Capture, or NS1 Elisa test, to confirm dengue but few people opt for.
The more popular confirmatory test is the rapid NS1 antigen test that gives results at the half the cost. Data from just 10 of the Delhi's largest private and government hospitals confirms this.
Fortis hospitals (Vasant Kunj, Karol Bagh and Shalimar Bagh) have confirmed 474 cases, Apollo hospitals 200, Moolchand Medcity 315, BL Kapur super-speciality 394, and Gangaram hospital 455 cases.
Among the government hospitals, AIIMS got more than 200 cases, Lok Nayak 250, Deen Dayal Upadhyay 300, and Guru Tegh Bahadur more than 450.
"Private hospitals also get patients from outside Delhi, which we do not count as Delhi cases," said NK Yadav, medical health officer, South Delhi Municipal Corporation.
"Moreover, we only accept Elisa test as the confirmed dengue test which most hospitals do not perform."
Delhi has 39 government and more than 40 private hospitals. It is not possible to collect data from smaller nursing home and private practitioners.
All casualties this season, including Sejal Sachdeva, who died at Bhagwan Mahavir Hospital in Pitampura on Wednesday, have been children below the age of 12.
CM Sheila Dikshit on Tuesday blamed the civic bodies for not doing enough to check dengue.
A day later, all the three BJP-ruled civic bodies hit back, saying the government was not giving them enough funds.