The number of deaths in India from an outbreak of dengue fever reached 107 on Wednesday, as authorities struggled to contain the mosquito-borne virus.
"Four people who were admitted here died this (Wednesday) morning," said an official at the All Indian Institute of Medical Sciences (AIIMS), the country's premier facility in New Delhi.
A federal health ministry statement said 5,710 cases and 103 deaths from dengue -- a viral infection transmitted to humans through bites of female Aedes mosquitoes -- had been reported across the country till late Tuesday.
New Delhi and neighbouring states have been worst hit by dengue with 1,637 cases followed by southern coastal Kerala state which reported 794 cases, the health ministry said.
Dengue causes a severe, flu-like illness and can lead to internal bleeding.
School children in New Delhi and some other parts of the country where dengue has been reported have been ordered to wear their winter uniforms to protect their skin from mosquito bites.
AIIMS admitted 27 news cases on Wednesday and has set aside some 300 beds for dengue patients, an official said.
Besides dengue, an outbreak of chikungunya -- another viral disease spread through the Aedes aegypti mosquito -- has affected 1,651 people nation-wide.
The government of the southern coastal state of Kerala said last week the disease had claimed 86 lives. But the federal government said the deaths were not directly attributable to chikungunya as the victims had been weakened by other conditions such as heart problems.
Chikungunya -- a Swahili word for a stooped walk that reflects the physique of a person suffering from the virus -- causes high fever and headache, but is rarely fatal, according to the World Health Organisation (WHO).
A WHO website statement said of Chikungunya that "more than 1.25 million suspected cases have been reported from the country."
"Affected states are Andhra Pradesh, Andaman and Nicobar Islands, Tamil Nadu, Karnataka and Kerala (in south India), Maharashtra, Gujarat (in western India), Madhya Pradesh (in central India) and (the capital) New Delhi," it said.
Despite the high incidence of mosquito-borne diseases during the height of India's tourist season, there were no cancellations of tourist reservations, travel operators said.
"We've not had cancellations (from clients in Europe)" said a spokesperson from the Kuoni Travel Group, a subsidiary of Switzerland-based Kuoni Travel Holding.
An official of Delhi-based inbound tour operator Ibex Expeditions Private agreed, saying, "No one has cancelled bookings."
Tourist arrivals rose over 13 percent between January and September to three million from 2.7 million in the same period last year, a federal tourism ministry official said.
But officials in Kerala, a popular tourist destination, said they were receiving inquiries about whether it was safe to come to India this winter.
"We're getting many inquiries from Europe asking whether it's safe to travel to India and our answer is yes, it's safe, come on over," said E.K. Bharat Bhushan, Kerala Tourism principal secretary.
Checking the proliferation of mosquitoes is the main preventive measure for both dengue and chikungunya, which strike during the rainy season when mosquito-borne illnesses affect tens of thousands of Indians.
A dengue outbreak in Delhi claimed more than 400 lives in 1996 when 10,000 people contracted the virus.