LAHORE Rains in parts of the country coupled with snowfall over the hills and northwesterly winds have caused considerable decrease in the mercury level, heralding early onset of winter and thus relief from the menace of dengue about fortnight earlier than expected. At present, the minimum temperature is about 2-3 degree Celsius below normal level in parts of the country, especially beneficial in the dengue hit Lahore. The mercury has already dropped as low as 17 C in Lahore, the temperature normally experienced during the first week of November. On good rain and the mercury will drop further that will end growth of vector Aedes Aegypti mosquitoes and will ultimately reduce the dengue cases, the experts say. Westerly wave set in earlier and give much needed rainfall over plains and snowfall over the hills. Rains and northwesterly winds caused decrease in the mercury level over the plains including Lahore. In plains of the province including Lahore, the minimum temperature is 2-3 C below normal level. As such people are experiencing early November like late nights and mornings, said meteorological expert Shaukat Ali Awan, adding, the temperature would continue to fall in coming days and mornings and nights would be chilly at the start of November. Medical experts have termed early rains, snowfall and northwesterly winds good omen as these have helped decreasing the mercury level that could stop emergence of new dengue cases. Chances of bite will decrease with the drop in mercury level as it will stop conversion of larva into mosquito. Further decrease in temperature will put to an end the emergence of new cases at least during the current calendar year. Nature has come to the rescue of poor Lahorites and early onset of winter will give much needed relief, said Principal Allama Iqbal Medical College Prof Javaid Akram, adding, people in the congested localities should remain careful especially during the evening till mid November and avoid mosquito bite. No new larva will become a vector when temperature falls below 15 C. But people should take care as already existing mosquitoes will still be a threat. Elimination of these mosquitoes when the temperature is persistently below 15 C will stop emergence of fresh dengue cases, he said while suggesting the government to take concrete steps including proper public awareness about larva sites, biological control of mosquito growth, larviciding and measures to change genetics of vector to check reemergence of the menace after this winter.