Warming Ontario could face tropical diseases
West Nile virus only a precursor to what will happen, report warns

Canadian Press OTTAWA （By Dennis Bueckert October 23, 2002）― People in the Toronto-Niagara region can expect increased exposure to malaria（疟疾）, dengue fever（登革热）and hantavirus in coming years due to climate change, says a major new report.

The diseases are projected to spread because climate change favours the northward movement of disease-carrying birds, insects and rodents, says the study obtained by The Canadian Press.

The sudden spread of West Nile virus is an example of what to expect, suggests the study done by Pollution Probe in partnership with Health Canada and Environment Canada.

It’s the first comprehensive examination of the likely effects of climate change on an urban area in Canada.

“The health implications (of climate change) are pretty severe,” Quentin Chiotti of Pollution Probe, one of the authors of the study, said in an interview Wednesday.

“How prepared are we to deal with these kinds of risks? We need to develop a very co-ordinated, comprehensive strategy involving national, provincial and municipal players to effectively respond.”

That’s because heavy rains would increase the risk of contamination of drinking water. Water-borne disease outbreaks in the United States have been linked to heavy rain storms.

Scientists have long predicted global warming will result in the northward spread of diseases now confined to hot countries, but the arrival of West Nile virus has made the risk more tangible.

In the past, severely cold winters could be counted on to kill many disease vectors, but there has been a trend to mild winters.

Experts such as Paul Epstein of Harvard Medical School have said the spread of West Nile virus to the Western Hemisphere is probably due to climate change, notably milder winters.

“What’s scary to me is that there are now 69 (suspected cases of West Nile Virus), 20 confirmed, in Canada,” said Chiotti. “That’s a fairly quick and rapid spread.”