NEW DELHI (AP) _ India's health minister said Thursday that the death toll from an outbreak of dengue fever had risen to 38 as hospitals struggle to cope with an influx of patients.

In southern India, meanwhile, a rare mosquito-borne viral fever known as chikungunya killed another four people overnight, bringing the death toll from that disease in the state of Kerala to 75 in the past month, said the state's health ministry.

The dengue outbreak has largely hit the country's north, and 2,900 suspected cases have been reported in the past six weeks with 38 of those infected dying, said Health Minister Anubani Ramadoss.

Relatives of Prime Minister Manmohan Singh may be among those hit, with two of his grandsons and a son-in-law hospitalized in New Delhi with dengue symptoms, Shakti Gupta, a spokesman for the All India Institute of Medical Sciences, said Thursday.

``The condition of all the three patients is stable. Their symptoms are being monitored and assessed,'' Gupta told reporters.

The outbreaks of dengue and chikungunya come as the annual monsoon season tapers off, leaving puddles of stagnant water where mosquitoes breed.

Female Aedes mosquitoes transmit dengue. Symptoms include high fever, joint pain, headache and vomiting. It is fatal in rare cases. India's annual outbreak normally dies off with the end of the mosquito breeding period in November.

Municipal authorities have been working to spray pesticides in New Delhi, where 15 people have died, and surrounding areas in recent days.

``Definitely, we are tackling the situation and this is not an epidemic and in the next few days to come we expect the cases to reduce,'' Ramadoss said.

He added: ``The situation is being controlled. There is no need to panic.''

In the southern state of Kerala, tens of thousands were reported to be suffering symptoms of chikungunya, such as high fevers and severe joint pain, and many of them had been hospitalized, the state's health ministry said.

A World Health Organization team was also reportedly in the state and working on ways to stem the outbreak.