LONDON (Reuters) - Nearly 80 percent of the 300,000 conflict-related deaths in Darfur were due to diseases like diarrhea, not violence, Belgian scientists said on Friday.

An analysis of deaths dating from 2003, when rebels took up arms against the government of Sudan, showed that after an initial peak of violent deaths in the still-ongoing conflict, diseases associated with diarrhea became the major killers.

The researchers said their results showed that any reduction in humanitarian aid can cause deaths rates to increase sharply, raising “serious concerns” about the consequences of last year’s expulsion of aid workers from Sudan by the country’s president.

“We should fear the worst,” they wrote in a study in The Lancet medical journal.

Since the armed rebellion started in early 2003, the United Nations estimates 300,000 people have died and more than 2 million have been driven from their homes after a counter-insurgency campaign by Khartoum.

“More than 80 percent of excess deaths were not a result of the violence,” said Olivier Degomme and Debarati Guha-Sapir of the Center for Research on the Epidemiology of disasters in Brussels.

They said a violent peak in early 2004 was followed by “protracted phase of increased disease-related” deaths caused by people living in conditions of unsanitary conditions with little or no healthcare infrastructure.

Diarrhea kills some 1.5 million children each year around the world - more than AIDS, malaria and measles combined.

There are three main forms - acute, bloody and persistent - all of which are potentially life-threatening.

“Adequate humanitarian assistance to prevent and treat these potentially fatal diseases is essential,” Degomme and Guha-Sapir wrote. “The full effect of the expulsion of non-governmental organizations from Darfur is still not known, but the increased mortality rate during a period of reduced humanitarian deployment in 2006 suggests that we should fear the worst.”

The International Criminal Court last year issued an arrest warrant for Sudanese President Omar Hassan al-Bashir for war crimes in Darfur. He rejects the court’s authority and puts the death toll at 10,000.

SOURCE: The Lancet, January 22, 2010.