Over 80 percent of the fatalities in 2005 came from a single disaster - October's devastating earthquake in Kashmir and Pakistan's North West Frontier Province - just as the tsunami caused over 90 percent of deaths a year earlier.

Without the earthquake and the tsunami, the death toll in both years was under 20,000, confirming a trend for more frequent, but less lethal disasters.

"That is the goods news," said professor Debarati Guha Sapir, of the Louvain Centre for Research on the Epidemiology of Disasters (CRED).

The bad news is rising urbanisation, with people in developing countries often crowding into environmentally dangerous areas around big cities, meaning the risk of disasters is growing, said ISDR director Salvano Briceno.

"These figures reaffirm trends we have been observing for the past decade," he said. "Fewer people are dying from disasters, but there are many more long-term, negative implications for sustainable human development," he said.

"Countries and communities need to understand their risks, invest in resources and prioritise their policies to reduce their vulnerability to natural disasters," he said.

In 2005, there were 360 natural disasters, ranging from hurricane Katrina, which killed 1,322 people in New Orleans, to a measles epidemic in Nigeria in which more than 500 died.

Floods and droughts made up 237 of the total.

Disasters affected the lives of 157.5 million people - meaning they were killed, injured, required immediate assistance or evacuated - up from 150.4 million the year before.

"The increase (in disasters) is mainly due to the rising numbers of floods and droughts that affect large swathes of a population," said Guha Sapir.

But droughts and floods tend to be less deadly than earthquakes and storms, hence the lower death tolls, she added.