 Millions more South Asians will suffer from diseases like malaria and cholera, or go hungry due to global warming, but governments are not fully aware of the dangers, the World Health Organisation said on Thursday. A United Nations climate panel report last month predicted climate change would result in temperatures rising by between 1.8 and 4.0 Celsius (3.2 and 7.8 Fahrenheit) in the 21st century. But the WHO's environmental health adviser for South Asia, Alex Hildebrand, said little attention had been paid to the impact rising temperatures would have on the health of the region's 1.4 billion people. "There are so many impacts to human health such as vectoral and water-borne diseases, thermal stress and dehydration and malnutrition," Hildebrand told Reuters in an interview. "This issue needs to be prioritised by governments and health professionals ... The link between climate change and human health is still not known even at the highest levels of government. We need to promote awareness on this." South Asia, home to more than one-sixth of humanity, is considered particularly vulnerable to climate change with low-lying countries such as Bangladesh, Himalayan glaciers, desert areas and huge populations in coastal cities. Hildebrand said the predicted increase in temperature will lead to areas such as the Kathmandu Valley in Nepal and Timpu, Bhutan's capital, and parts of India becoming more susceptible to mosquito-borne diseases. "Diseases like malaria, Japanese encephalitis, tick-borne diseases and dengue fever will definitely thrive in warmer climates," he said. South Asia gets around 20 million cases of malaria every year. Greater frequency of droughts and heatwaves will not only adversely affect crops but will also punish those who live with a scarcity of water and push up rates of respiratory illness. At the same time, increased rainfall will trigger damaging floods along rivers. "Floods will bring more drownings as well as water-borne diseases like cholera and diarrhoea to many more places like Bangladesh and cities like Mumbai and Chennai," he said. Diahorrea already kills about 600,000 people every year in South Asia, he added, and governments will struggle to cope with the extra health burden.