DIGOS CITY ? A dengue epidemic has been declared in Davao del Sur following the continuing increase in the number of patients stricken ill by the mosquito-borne disease.

Doctor Azucena Dayanghirang, provincial health chief, said Tuesday that the staggering number of victims ? with nine deaths from January to July in this city alone ? had prompted health officials to declare a dengue epidemic.

Dayanghirang said nearly 700 more people have fallen ill and hospitals are already congested with dengue patients.

Most patients came from this city.

Doctors said what baffles them is the rate by which the virus is spreading.

A doctor, who requested anonymity, said former dengue-free villages in the province are now reporting cases of the mosquito-borne disease.

?There also seems to be a new strain spreading. It?s deadlier,? he said.

Among those hit by an apparent new strain was five-year-old Princess Coronado, who had to undergo plasma replacement because of severe internal bleeding.

?There is also a suspicion that the virus was mutating into a more deadly strain,? the doctor said.

Dayanghirang said epidemiologists from the Department of Health Central Office have started collecting samples from dengue patients to test whether, indeed, a new strain has developed.

Dayanghirang said results of the tests might be known next week yet.

She said the provincial government continues to assist dengue patients, who cannot afford hospitalization.

Dayanghirang said the assistance was drawn from the province?s calamity fund, which was released after Gov. Douglas Cagas approved the declaration of a state of calamity.

But she said residents should also help in preventing the spread of disease because it would not only save them money but the lives of their loved ones as well.

Dayanghirang said residents should deny dengue-carrying mosquitoes their breeding grounds by emptying idle containers of water and cleaning their surroundings.

?We have intensified our campaign, house to house, to urge the people to clean their backyards,? she said. Orlando B. Dinoy, Inquirer Mindanao