The outbreak originated in northern Nigeria, where the government of Kano State had banned polio immunizations, the W.H.O. said.

In a study in Iran in 1956 it was found that outbreaks of locusts originated from just eight distinct areas.

The outbreaks, caused by the salmonella bacteria, most often originate with eggs, poultry or undercooked meat and cause diarrhea, abdominal cramps, fever, nausea and vomiting.

On Thursday, a government spokeswoman said there was no evidence that the outbreak of avian flu had originated in China.

The field where the outbreak has originated may be grazed by sheep or rested until the following June.

Experts are still unable to say where the outbreak originated, having ruled out the initial theory that it came from a consignment of Spanish cucumbers.

It is obvious that Britain's first outbreak originated outside the Community, and I now question whether third countries which export to us are complying with the conditions we have imposed.

I would say to him that we still do not know where this outbreak originated.

Past outbreaks of avian flu have often originated in crowded conditions in southeast and east Asia, where humans, pigs, and poultry live in close quarters.

Officials from Maple Leaf believe that the outbreak originated sometime in July on line 8 or line 9 of the North York facility.