A new Health Canada report warns Canadians of the potential health risks of climate change, including spikes in heat-related deaths, an increase in respiratory and cardiovascular problems, and the spread and emergence of diseases.

"The findings of this assessment suggest the need for immediate action to buttress efforts to protect health from current climate hazards," says the 500-page report, entitled Human Health in a Changing Climate: A Canadian Assessment of Vulnerabilities and Adaptive Capacity.

It examines the effects under three categories: extreme weather events and natural hazards, air quality and heat, and diseases transmitted by water, food, insects, ticks and rodents.

The projected increase of floods in some areas and drought and forest fires in others are some of the natural disasters caused by climate change that will cause health-related problems, the report says.

As well, a rise in heat waves will be accompanied by an increase in heat-related deaths, the report says, with the greatest risk to cities because of higher population densities and the urban heat island affect.

Those at greater risk are people aged 65 and older, with summer mortality rates projected to be two to three times greater than for those aged 15 to 64, the report says.

Quebecers are singled out in the report, as they are noted for historically being able to adapt well to very cold temperatures "but have not been as successful adapting to extreme heat."

The report also focuses on how the increase in global temperature will affect the air Canadians breathe by increasing smog, wildfires and pollen production.

For example, an increase in the formation of ground-level ozone could lead to more respiratory and cardiovascular problems.

Based on a four degree increase in average temperatures, the report projects 312 more premature deaths each summer because of increase in ozone and a 4.6 per cent or $1.366 billion increase each summer in the health burden to Canadian society related to air pollution.

Climate change may also increase the spread of some infectious diseases, with the increase in temperatures allowing them to survive longer. More rain in some areas and more frequent droughts could increase risks of water contamination and water-bone disease outbreaks, the report warns.

Report predicts more avalanches, slides in North

Milder winters, heat waves and summer droughts could affect mosquito and tick populations, triggering the spread of West Nile virus and Lyme disease, the report says.

"Climate change could tip the ecological balance and trigger outbreaks of disease previously rare or unknown in Canada," the report states.

The report also says that communities in Canada's North are most vulnerable to climate change. Avalanches and landslides are projected to be more frequent. Northern communities will also have to contend with food shortages and less clean drinking water.

Speaking to reporters at the Conservative caucus retreat in the rural Quebec town of Levis, Health Minister Tony Clement said Canadians will "have to get used to" the gloomy scenario laid out in the report.

"This report makes it clear that if you have bad health outcomes now, you're likely to be more impacted by extreme weather events than if you're at the top of the health ladder," he said.

The report urges Ottawa to do more to help Canadians adapt to climate change. It cites "significant barriers to adaptation" that include a lack of knowledge of health risks and uneven access to protective measures across the country.

With files from the Canadian Press