Two children aged six were among those diagnosed with the mosquito-borne disease on Friday.
There is a suspected dengue death of a four-year-old girl from Janakpuri.
A nine-year-old girl from Sangam Vihar had died of the disease at the All India Institute of Medical Sciences on September 24.
Hers was declared the first dengue-induced death in the city by the public health department of the South Delhi Municipal Corporation.
The number of dengue cases has shot up recently because of the weather that is thought to be ideal for mosquitoes to breed.
City hospitals have reported nearly five times more cases than the civic agencies.
In Gurgaon, a 63-year-old woman from DLF Phase I and a 60-year-old man from Sector 56 tested positive for the H1N1 virus at the Alchemist Hospital last week. They complained of acute respiratory symptoms.
The return of the H1N1 swine flu virus to the Capital's neighbourhood has prompted the Delhi government to take precautions to prevent its spread in the city.
"No case of swine flu has been reported in Delhi. I will meet officials of departments concerned from the civic agencies and blood banks to chalk out a strategy," Dr AK Walia, Delhi's health minister, said.