LAHORE - Even though it has made significant effort to eradicate the vectors and breeding grounds of the dengue virus, the Punjab government is still not focusing on the root cause of the deadly epidemic: the source and reservoir of the virus which has been sustaining the disease cycle on such a large scale, Pakistan Today learnt on Thursday. The Punjab government has so far put all its energy and resources into patient management and eliminating the mosquitoes through fumigation, spray and larvicide. Even the teams of experts from Sri Lanka and Indonesia have helped health officials identify the breeding sites of the dengue vector (the aedes aegypti and aedes albopictus mosquitoes) and provide better treatment facilities to dengue patients.
The government, on its part, has released million of rupees to the City District Government Lahore (CDGL) for fumigation and to the Health Department and hospitals for treatment and diagnostic facilities. Recently, the government initiated a campaign to destroy dengue larvae at the warehouses of tyre shops, workshops and other places, also imposing Section 144 on the sale of old and used tyres.
However, it has completely ignored the root cause sustaining the deadly epidemic on such a large scale: the source of the dengue virus.
Medical experts believe that efforts to curb the deadly epidemic in the coming years will not yield results unless the dengue virus is studied in isolation because no one has ascertained yet if the larvae or eggs of vector mosquitoes were infected with the dengue virus. Besides, they said a “sudden and unexpected” epidemic on such a large scale could not be sustained by the mosquito and human population alone, considering it was never an indigenous disease.
“A vector carries the virus and transfers it to a human, turning both the mosquito and the patient into reservoirs of the virus… however, the life cycle of a dengue mosquito ranges between 30 days and 60 days according to various international experts and a dengue patient carries it for almost 10 days during the illness, after which that particular strain of virus is no longer in the human body. The dengue epidemic hit us before time, unexpectedly and spread in an aggressive manner all pointing towards other reservoir virus hosts which maintained the epidemic at such a large scale… without identifying that reservoir and source of dengue virus, no one can devise a comprehensive plan to overcome the menace of dengue,” Mayo Hospital Microbiology Head Dr Tayyaba told Pakistan Today.
She said further that no one had yet isolated the virus from the infected mosquito, adding: “They have yet to identify even the serotype of dengue virus 1, 2, 3 or 4. Has anyone isolated the virus from the eggs, larvae or mosquito from our areas so that we can claim on scientific basis that either eggs or larvae were infected with dengue virus in reality?”
She revealed further that international experts had claimed that lower primates could be possible hosts of dengue virus and the zoo could be a possible disease spreading centre. International experts had further reported genetic structural changes in the mosquito, enabling it to develop a resistance against certain anti-mosquito sprays and chemicals such as deltamethrin and temephos. “The mosquito is only the vector that transfers the virus into humans, it is not the source of the virus and probably not the only reservoir of dengue as well, evident from the large scale outbreak in the provincial capital this year,” Dr Tayyaba said, adding that a comprehensive methodology covering the virus, mosquito and humans should be devised to break the disease cycle, without which Pakistan stood at risk of facing a far severer return of the epidemic next year.
CDC Director Dr Malik Mubashar told Pakistan Today the government had made every possible effort to crush the deadly epidemic, adding that foreign experts had also been included in the government’s endeavours to fight dengue. “The study of the virus is important to curb dengue, no doubt, but Pakistan does not have the requisite labs and technology to conduct a study of the virus in isolation,” he said. Such labs were available only in developed countries, he said, but the World Health Organisation (WHO) could be of help in this regard as Pakistani authorities had an arrangement with the WHO to seek such kind of help and expertise.