LAHORE, Nov 11: All dengue fever cases reported in Lahore so far are from urban areas, it is learnt.

Health department officials said on Saturday that none of the three dozen cases had been reported from slums, indicating that either the mosquitoes caused the disease did not exist there or owing to lack of resources its population could not admit patients to the public hospitals of the city.

Most of the dengue fever patients belong to Misri Shah, Shadbagh, Allama Iqbal Town, Sabzazar, Sanat Nagar, Mughal-pura, Defence and the Walled City. Most of them are male and aged between five and 65.

“Ideally the provincial health department should ask the city district government to immediately fumigate the areas where dengue cases have been reported. However, due to public pressure the district government has launched the fumigation campaign across Lahore, which is yet to be completed. There has been no coordination between the two departments either in this respect,” a senior officer said.

He said the exact number of such cases could not be ascertained because the government was not maintaining the data of the (suspected) patients coming in private hospitals. He suggested the government teams should also visit the clinics near slum areas to check the incidence of the disease.

He confirmed that only three of 36 dengue patients developed Dengue Haemorrhagic Fever (DHF) known as viral haemorrhagic fever, the second stage of the disease, which often resulted in death. However, he claimed that they had been recovered.

“DHF is a cause of death and only people with antibody develop this fatal form of disease. Therefore, only individuals who have recovered from dengue fever are susceptible to DHF. On a second exposure to the virus, these antibodies facilitate entry of virus into the body defence cells known as macrophages where the virus grows rapidly. However, in case of dengue fever, a patient initially feels flue-like symptoms and suffers from high fever, headache, eye pain, severe joint and muscular pain, nausea, vomiting and skin rashes,” he explained.

Experts say that the second spike of mosquito transmitted dengue fever and dengue hemorrhagic fever is the direct outcome of the combined negligence of public health institutions and district governments. Poor sanitation facilities in thickly populated areas invite mosquito breeding, resulting in malaria and dengue outbreak.

Differentiating the dengue fever from the common (fevers) the experts say that commonly dengue virus is suspected when one has sudden onset of high grade fever (103-105 degrees F), accompanied with several headache (mostly in the forehead), body aches, rashes on the skin and nausea or vomiting. The fever lasts for five to seven days.

They say that the method to prevent the disease is combating the vector mosquitoes. Dengue fever is caused by a specific mosquito that bites humans during daylight, especially around the time of sunrise and sunset.

EDO (health) Dr Inamul Haq said the preliminary result of the blood samples of three more patients had been found positive.