Statistics from the National Vector Borne Disease Control Program (NVBDCP) show that the state recorded 677 cases after Maharashtra (963) and was followed by Kerala (651).

According to experts, in the state's rural areas, acute water shortage forces people to store water in vessels that help breed mosquitoes. The growing construction activity and piling up of garbage are also behind the spike in dengue cases.

"Recent rains caused water stagnation in some areas and resulted in the increase in the numbers of Aedes Aegypti - the mosquito that causes dengue," said a senior official admitting that cases of dengue were unusually high this year.

Public health officials, however, said that the figures are not alarming and action has been initiated to remove all possible places where water can stagnate, including discarded tyres, plastic bags and containers. A senior official said that the reporting system in TN was better than in any other state. He said, "We have instructed all hospitals to report every case. Several awareness campaigns have been conducted."

In an advisory to all nodal officers across the country, NVBDCP director Mr Anil Dhariwal said, dengue was the fastest emerging infection amongst all vector-borne diseases because of several human and environmental factors. He added, "Last year, we observed circulation of DEN-2 virus in some states which needs to be stopped this year."

According to the World Health Organisation, people with dengue fever should rest, drink plenty of fluids and reduce the fever using paracetamol or see a doctor.