Updated

The Israeli Health Ministry confirmed Friday that three farm workers were taken to hospitals to be tested for exposure to bird flu.

Results on blood taken from the workers could come later tonight or tomorrow, an Israeli official said.

The possible human infections came as tests showed the deadly H5N1 bird flu was likely responsible for killing thousands of turkeys in various farming communities in the Negev Desert.

Israeli media reported that results from a test called PCR came back positive for the deadly strain of the flu in the birds, but the results would not be accepted as conclusive by the World Health Organization. Officials said they are awaiting results from a stricter test, which are expected by Sunday.

Israeli officials on Friday ordered tens of thousands of turkeys destroyed and quarantined the suspected areas while halting all exports of unprocessed chicken and turkey meat to overseas destinations.

Health officials fear H5N1 could evolve into a virus that can be transmitted easily between people and become a global pandemic, but there has been no confirmation of this happening yet. At least 97 people have died from the disease worldwide, with most victims infected directly by sick birds.

The suspected outbreak originally was centered in Ein Hashlosha and Holit, but later spread to Nachson, a farming community near Jerusalem.

Israeli media reported that the three farm workers were taken to the Soroka Medical Center in Be'er Sheva after complaining about feeling sick for the past few days. One patient, a Thai laborer who works in Ein Hashlosha, was being held in isolation.

Four million units of flu vaccine for birds were ordered from Holland, Agriculture Minister Zeev Boim told Israel Radio.

Yarisca said Israel, in cooperation with the Palestinian Authority, regularly tests chickens from Gaza for avian flu, and so far, the flocks there have aroused no cause for concern.

The H5N1 virus was detected in neighboring Egypt last month, and Boim said Thursday that the death of the birds in southern Israel might indicate the disease entered Israel from Egypt.

The H5N1 strain has killed or forced the slaughter of tens of millions of chickens and ducks across Asia since 2003, and recently spread to Europe, Africa and the Middle East.

Officials said there was no danger of infection from eating cooked chicken, turkey or eggs.

The Associated Press contributed to this report.