Health officials in western Japan abandoned efforts to pinpoint the carrier of a killer germ in school lunches and took a controversial step Monday to distribute antibiotics to victims of the bacteria.
Researchers failed to detect the O-157 bacteria from some 1,500 food samples from school lunches prepared at several central locations and delivered to 92 primary schools in the port city of Sakai in western Japan.
"We have conducted tests on all possible food samples, but we have not been able to find the O-157 germ," a spokesman for the task force in Sakai said. "We were forced to abandon our efforts."
He said health officials would shift their focus away from school lunches to food distribution channels.
Seven people have died and nearly 9,000 people have been sickened since the epidemic of food poisoning began two months ago. About 6,500 people, mostly schoolchildren, have contracted the illness in Sakai alone.
Health officials in Sakai started handing out antibiotics to some 200 people who tested positive to the bacteria in "voluntary" health examinations but have shown no symptoms of the infection, the spokesman in Sakai said.
But some experts say that although antibiotics can kill the bacteria in a patient, the process could result in the release of toxins the microbe has produced and kill the patient.
And some doctors warned that if the microbe was not killed by antibiotics, a patient could become a carrier even after recovery, worsening the spread.