Poor vector surveillance may increase chances of dengue outbreak

Rawalpindi : The possibility of a severe dengue fever outbreak in the coming months in this region of the country may not be ruled out as the larvae of ‘aedes aegypti’, the vector that causes dengue fever are being found in abundance in the district.

Data collected by ‘The News’ on Saturday has revealed that the density of larvae being found by the teams of District Health Authority Rawalpindi is much higher in a number of localities falling under the jurisdiction of Municipal Corporation Rawalpindi, Potohar Town, Rawalpindi Cantonment Board and Chaklala Cantonment Board despite the fact that the vector surveillance is less strong this year as compared to the surveillance in the year 2022 and 2023. 

Data reveals that at this point in time in 2022, as many as 2196377 spots were checked by the district health department under the vector surveillance and in 2023, the number of spots checked was 2329714 while this year so far, a total of 1372873 spots have been checked for dengue fever vector recording significantly a low level of surveillance. The number of spots tested positive under the vector surveillance, however, is still higher as compared to the spots tested positive in the year 2022 and 2023.

Till April 27 in 2022, the dengue fever vector was found from as many as 2844 spots, in 2023, the number was 2,552 while this year, 3,080 spots have been tested positive till April 27. The data also reveals that at this point in time in 2022 and 2023, the teams of district health department Rawalpindi checked as many as 981,000 houses and 959,225 respectively while this year, the teams have so far checked a total of 361,501 houses for dengue fever vector. The number of houses tested positive is still much higher this year as the vector has been found from a total of 732 houses so far. In 2022, 332 houses were tested positive till April 27 while in 2023, the number was 382. Experts say that the vector surveillance system needs to be strengthened to take measures well in time for prevention and control of dengue fever outbreak. It is a proven fact that a weak vector surveillance system increases the chances of a more severe dengue fever outbreak in a region.

The situation may be termed as alarming particularly because almost all risk factors including rains, rising temperature, infected travellers and heaps of garbage and rubbish dumps along with larvae of dengue fever vector and adult mosquitoes are very much in existence in this region of the country. It is important that as many as four confirmed patients of dengue fever have already been reported from Rawalpindi district. Also the most suitable season for breeding of dengue fever vector has almost set in. Experts say that a possible outbreak of dengue fever can be avoided by avoiding breeding of mosquitoes and by controlling their growth inside and outside homes at the time. It is time to take precautionary measures religiously by both the concerned government authorities and the individuals. Health experts believe that the community has to destroy possible breeding sites of mosquitoes mechanically that can harbour larvae to develop into adult mosquitoes as it is a must to avoid a possible outbreak of dengue fever.

The dengue fever mosquitoes both ‘aedes aegypti’ and ‘aedes albopictus’ are vectors that cause dengue fever as the female ‘aedes’ mosquitoes carry one of the four types of dengue virus from the dengue patient to the healthy person and transmit the disease. It is important that usually, the dengue fever vector lays the first eggs of the year at the beginning of May and the mosquito density is maximal in early July, late August and early September while the egg laying activity remains continued until November.