The state of Telangana is witnessing an alarming rise in the number of swine flu cases, with at least 496 people testing positive for the infectious seasonal influenza so far this year.

The India Meteorological Department has attributed the climate change to western disturbances combining with upper air cyclonic circulation over north-western regions of the country.

According to several studies, H1N1 virus spreads faster in colder weather conditions because they harden its surface, helping it survive for longer periods. Once the virus settles in the nasal passageways of humans, it adapts to the climate and attacks when the body’s immunity falls (which happens at colder temperatures).