``Of these, three are from Hadapsar, three from Bibwewadi, four from Prabhat Road and six from the patients admitted at the hospital,'' said Dr RR Gadia, consultant physician, who believes that the city is in the grip of a dengue outbreak and if immediate precautionary measures are not taken, it may result in a major epidemic.

On Monday, the KEM had received nine samples of which eight had tested positive, on Tuesday tests could not be carried out. ``The numbers are certainly increasing. Of the samples received today (Wednesday), half have turned out to be positive, which means that we are on the right track,'' said Gadia.

Meanwhile, the detailed addresses of the 54 patients who tested positive for dengue earlier will now be handed over to Dr Anil Ravitkar, Chief Health Officer, PMC. In thepast two months, of about 100 blood samples tested by 50 doctors working with the KEM project, 50 per cent were found positive for dengue antibodies. Of these, 30 per cent had bleeding from the gums, nose or blood spots, an advanced condition that needs immediate hospitalisation.

Citizens have been advised not to leave stagnant water for more than a few days in and around their houses as it breeds the aedes aegypti mosquito, vector for the dengue fever.