"People are now aware of the virus and when they suspected a case they reported it to us. The bird flu has hit our country again," said Agriculture Ministry official San Vanty.

Bird flu first hit Cambodia in September last year, but the virus which has killed humans in neighbouring Vietnam and Thailand did not claim its first Cambodian victim until last month, when a 25-year-old woman succumbed in Vietnam.

Officials in the war-scarred southeast Asian nation, which is still recovering from the Khmer Rouge genocide of the 1970s, conceded they are unable to do much in the face of a highly contagious and invisible enemy.

"Even though we have no new suspected cases, it is still a worry for us because we have a poor health system," San Vanty said.

However, health ministry officials said tests had shown that the province of Kampot where the female Cambodian victim lived close to the Vietnam border, did not have any H5N1 cases.

"She could had been affected by the virus from another place," said Sok Touch, head of communicable diseases at the Ministry of Health.