Global Warming Trends Contribute to the Spread of West Nile Virus to New Regions in Europe

Global warming trends have a significant influence on the spread of West Nile virus to new regions in Europe and neighboring countries, where the disease wasnt present before, according to a new study by the University of Haifa. The study was commissioned by the European Centre for Disease Prevention and Control (ECDC) in Stockholm, which belongs to the European Union. The study found that rising temperatures have a more considerable contribution than humidity, to the spread of the disease, while the effect of rain was inconclusive.

These results are an additional testament that global warming contributes to the outbreak of mosquito-borne and other temperature-sensitive vector-borne diseases. The indications to this are piling up in different parts around the globe, says Dr. Shlomit Paz, who led this research. These findings were recently published in the online scientific journal Plos One.

West Nile virus is spread by mosquitoes that repeatedly bite infected birds. The potential threat the infection poses to man is the possibility of causing irreversible brain damage or even death through encephalitis or meningitis. The elderly and people with weak immune systems are most susceptible.

The research, conducted by a team from the University of Haifa led by Dr. Shlomit Paz, also included Dr. Dan Malkinson and Gil Tzioni from the Department of Geography and Environmental Studies, along with Prof. Manfred Green, the head of the School of Public Health, and in collaboration with Prof. Jan Semenza from the ECDC. The Israeli research team was chosen by the EUs ECDC, after winning an international tender.

The current study examined the link between daily temperature, humidity and precipitation data and West Nile incidence in Europe and neighboring countries. We used statistical tools and found that as a result of heat waves, a dramatic increase in the number of cases resulted from increased activity of the virus and a growth of the mosquito population, says Paz. According to her, these results were seen in various countries.

Paz says these results have a significant importance considering the rising temperatures seen in Europe in recent years. She is now conducting a continuing study on the subject for the ECDC and the French research center, CIRAD.

In our new research our aim is to look for additional potential influences on the spread of the disease, such as the location of mosquito populations or various human aspects, she says. Paz hopes their findings will make it possible to develop a model for better predicting the future spread of the virus in Europe, Such a model will allow the ECDC to guide the different European countries on how to better prepare in advance for West Nile outbreaks and perhaps will even allow restraint of such outbreaks in the future."

Source: University of Haifa