To count the dead they ride motorbikes, charter planes and wade through snake-infested rivers.

The precious statistic can help aid agencies convince a weary world there is a crisis in the jungles of Africa or forgotten corners of Iraq - where death comes from hunger and disease related to war as well as from war itself.

"There's a humanitarian crisis in Congo, (but) we need data to show there's a problem," said Richard Brennan of aid agency International Rescue Committee (IRC).

Its latest survey in the central African state found 45,000 people a month were dying from war-related hunger and disease, even though the conflict there had ended officially in 2003.

But pinning down precise, and credible, numbers is difficult and often intensely political. To prove its point, the IRC and other agencies have to go to where the dead are.

"It was really difficult to reach some places...We chartered airplanes and boats. We hired motorbikes," Brennan said.

One team came to a riverbank in Congo where the bridge had been washed away and waded across with a precious laptop perched on a team member's head. Villagers, heaving their motorbikes over the waist-high brown water, told them to watch out for snakes.

Other IRC teams visited communities living next to rubbish dumps the size of two-storey houses, and were given piggyback rides across open sewers to ask their questions about births and deaths.

Based on this arduous field work in a random sample of 14,000 households in every province in the country -- and Congo is the size of western Europe -- the IRC calculates the war dead since 1998 at 5.4 million; citing this as the deadliest conflict since World War Two.

The effort to provide scientifically grounded death tolls - calculating the death rate and comparing it to the regional norm - has boosted donations to help Congo recover from a conflict that sucked in seven nations and enveloped the region.



DEATH TOLLS IN IRAQ

The Congo surveys haven't been particularly controversial, but researchers trying to pin down a death toll for Iraq know their findings will come under intense scrutiny.

"People who oppose the war usually cite the highest death toll they can find, and people in favour of it tend to cite the lowest," said John Sloboda, who co-founded Iraq Body Count to collate reports from the media and mortuaries.

The British-based Web site - set up in 2003 before the start of the U.S.-led invasion - seeks to commemorate those who have died with entries that give the person's name whenever possible.

"It's just an act of humanity to record and memorialise the dead," Slobada said. "We've done it for soldiers for centuries."

While Iraq Body Count aims to provide an irrefutable minimum toll - currently 81,000 to 88,000 - others use methods more like IRC's Congo survey to extrapolate the full number of casualties.

The Iraqi Health Ministry and the World Health Organisation said this year they calculated 151,000 violent deaths between 2003 and 2006.

A team from Johns Hopkins University in the United States estimated as many as 654,000 deaths beyond the norm in Iraq during the same period.

A much simpler survey by British pollsters Opinion Research Business (ORB) put Iraqis killed by the war at approximately 1.03 million, based on a finding that 18 percent of the 2,414 adults they interviewed cited at least one death in the household due to the war.

ORB calculated its number using Iraq's last census in 1997 which documented 4.05 million households.



WAR-RELATED DEATHS

The IRC reports highlight the fact hunger and disease caused by a conflict often kill more people than the violence itself.

In Congo, for instance, intentional deaths count for less than 10 percent of the total. Most people die when they are cut off from food supplies or medical facilities, or because the hea,th system has been nearly eliminated by the conflict.

The IRC findings from Congo appear to mirror experiences in Angola, Liberia, Sierra Leone; all still struggling to recover from brutal conflicts.

And the remnants of war in Congo have pushed up the death rate despite the ceasefire.

Feared militias, government soldiers and renegade tribal fighters still prey on civilians and keep them from crops, safe water and health centres in the volatile east of the country.

Given the scale of the disaster - some 45,000 people a month dying from war-related hunger and disease, or the equivalent of a major football stadium - why doesn't Congo get more attention?

"People aren't dying dramatically," Brennan said. "They're dying quietly and anonymously ... In the eyes of Western powers, Congo doesn't represent major political or economic interest."