Islamabad - Residents of twin cities of Rawalpindi and Islamabad have been advised to properly dispose of solid waste at their houses to prevent access to egg-laying female mosquitoes. According to health experts, the people should avoid water storage practices and take other special preventive measures to protect themselves from dengue virus. They said mosquitoes breed primarily in containers like earthenware jars, metal drums and concrete cisterns used for domestic water storage, as well as discarded plastic food containers, used automobile tyres and other items that collect rain water.

Dr Sharif Astori of the Federal Government Poly Clinic (FGPC) said that dengue was a mosquito-borne infection, which in recent years had become a major public health concern.

He said dengue fever was a severe, flu-like illness that affects infants, young children and adults. He added the spread of dengue is attributed to expanding geographic distribution of the four dengue viruses and of their mosquito vectors, the most important of which is the predominantly urban species aedes

aegypti. He said the rapid growth of urban population is bringing even greater numbers of people into contact with this vector, especially in areas that are favourable for mosquito breeding like where household water storage is common and where solid waste disposal services are inadequate.

Dr Astori said dengue viruses are transmitted to humans through the bites of infective female aedes mosquitoes. He added that mosquitoes generally acquire the virus while feeding on the blood of an infected person.

He said after virus incubattion for eight to ten days, an infected mosquito is capable, during probing and blood feeding, of transmitting the virus to susceptible individuals for the rest of its life.

He said the virus circulates in the blood of infected humans for two to seven days, at approximately the same time as they suffer from fever. He added the clinical features of dengue fever vary according to the age of the patient.