"Varun was admitted to the ICU but his condition is quite stable now," said Dr Bir Singh, head of the Disease Prevention and Outbreak Response Cell.
He however said, that Sandhyal did not contract the vector-borne disease inside the campus as he had gone out of the campus for the past 10 days.
"He had gone out of AIIMS to his relative's place in Ghaziabad for 10 days and must have contracted the disease there. Our campus is free from mosquitoes," Singh, a professor of community medicine, told IANS.
A year ago, an MBBS student lost his life to dengue fever and a few other persons also were affected by it on the AIIMS campus. The cases then drew criticism from the public and raised serious concern over the sanitation level in the institute.
Stressing that the AIIMS was not to be blamed for the present case, Singh said, "The situation has improved drastically in comparison to last year. In this case, the student contracted the disease in Ghaziabad. But don't blame the institute for this."
"The incubation time for dengue fever is about six days. Varun must have got the mosquito bite outside, and his fever started in the campus after the incubation period," he said.
Speaking about one more student, who was admitted for treatment for dengue symptoms, Singh said, "Gaurav was in the general ward but his blood tests have not confirmed dengue. He is being treated for typhoid."
According to state health authorities, Delhi has reported 86 cases of dengue this year, but they said the situation was under control.
"We have received 86 cases this year, but 23 of them are visitors to Delhi from neighbouring states. The number of cases are less this year as compared to last year, when a total of 476 cases were reported," said N.K. Yadav, chief municipal health officer of Delhi.
This year, around 3,500 health officials are monitoring mosquito breeding in the capital city. So far, they have sent notices to 61,421 houses and fined some 13,213 households for breeding mosquitoes.