Climate change 'causing rise in flu epidemics': study

Climate change 'causing rise in flu epidemics': study

ISLAMABAD: The warmer winters believed to be caused by a changing climate tend to mean fewer cases of flu, but researchers say this is merely shifting the flu season to a different time of year when people are more vulnerable to it.

The season now starts earlier, lasts longer and produces a more virulent strain of the virus, according to mathematicians linking annual climate patterns to epidemics in the US.

They said that instead of occurring in winter, the flu season is starting in spring or autumn, Health news reported.

Part of the problem with that is that populations are less likely to protect themselves against the virus during mild weather, for example by having a flu jab, claim the researchers from Arizona State University.

This makes them more susceptible in the weeks after winter, according to the university's Mathematical, Computational and Modelling Sciences Centre.The researchers studied flu epidemics and weather patterns from 1997 to the present day, reporting their findings in the online journal PLOS.

Professor Sherry Towers, the lead researcher, said: "It appears fewer people contract influenza during warm winters and this causes a major portion of the population to remain vulnerable into the next season, causing an early and strong emergence.            "And when a flu season begins exceptionally early, much of the population has not had a chance to get vaccinated, potentially making that flu season even worse."

The US experienced a similar situation over the past year, she said.Dr Steven Riley, an infectious disease expert at Imperial College London, said the research was an interesting preliminary study.It was based on an assumption that climate change will make winters warmer, rather than an investigation on the subject, he said.