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Climate Changes Blamed For Deaths

Climate change may be to blame for some 150,000 deaths each year, with tropical places and poor countries being the most vulnerable, the United Nations' health agency said Thursday.

The increase in deaths estimated by the World Health Organization is a tiny fraction of 56 million deaths reported annually around the globe for all reasons.

Still, with some scientists warning that global warming could worsen over the next decades, and last summer's heat wave blamed for more than 20,000 deaths in Europe, U.N. officials urged more attention be paid to how climate change might be harming health.

WHO estimated that by 2030, climate change — which many blame on greenhouse gas buildup — could cause 300,000 deaths annually.

The WHO report, presented at a U.N. climate change conference here, blamed climate change for 2.4 percent of diarrhea cases and 2 percent of all cases of malaria worldwide.

WHO officials said the percentages were based on extrapolations of actual cases in sample places like Peru and Fiji.

Poor people who can't afford proper refrigeration are more likely to eat food tainted with increased bacterial contamination caused by higher temperatures. Similarly, stagnant water from floods is a breeding ground for malaria-carrying mosquitoes.

The toll of climate change on human health is still incomplete.

"We don't know what all the effects of climate change are likely to be," said Diarmid Campbell-Lendrum, a WHO scientist.

WHO officials said the toll from the European heat wave is still incomplete, since the agency is awaiting reports from some countries hard hit by the several weeks of soaring temperatures, including Germany.

WHO cited heat wave figures from some countries, including France's 14,802 "excess" deaths blamed on the heat spell. It said Italy had more than 7,000 "excess deaths in the over 65-year-old" group compared to the same period a year earlier, and Portugal had 1,300 heat wave deaths.

Dr. Bettina Menne, a WHO hygiene specialist, said London hospitals reported an increase in admissions of young children suffering renal problems, probably linked to dehydration during the heat wave.

Global warming in some situations will be expected to save lives, by making winters less severe, said Campbell-Lendrum.

"There will be winners and losers," the scientist said, adding that underdeveloped, tropical countries will see the highest toll from warming.

"In a tropical city like (New) Delhi, an increase in temperature is probably not going to save a lot of lives," said Campbell-Lendrum.

Much of Europe suffered heavily in the heat wave because air conditioning is not very common in homes, in part because of high-energy costs.

Installing more air conditioning in homes, workplaces, hospitals or residences for the elderly would also risk increasing the emissions of gases from the burning of fossil fuels like oil, gas and coal.

The accumulation of carbon dioxide and other "greenhouse" gases in the atmosphere is blamed for trapping heat, which is warming the globe.

Some scientists have urged caution about linking global warming to diseases such a malaria, saying mosquito-borne diseases are also linked to factors other than temperature increases, such as agricultural practices. And they have noted that malaria epidemics have plagued people in past centuries which were notably cooler that the last one.

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