BERLIN - Nearly 200 new cases of E. coli infection were reported in Germany in the first two days of June, the national disease control center reported Friday, but officials say there are signs the European bacterial outbreak that has killed 18 people could be slowing.
The Robert Koch Institute said that there are now 1,733 people in Germany - the epicenter of the outbreak - who have been sickened, including 520 suffering from a life-threatening complication that can cause kidney failure.
The World Health Organization said that as of May 31, nine other European nations have reported a total of 80 people sick from the bacteria, most of whom had recently visited northern Germany.
While suspicion has fallen on raw tomatoes, cucumbers and lettuce as the source of the germ, researchers have been unable to pinpoint the food responsible.
The outbreak is considered the third-largest involving E. coli in recent world history, and it is already the deadliest. Twelve people died in a 1996 Japanese outbreak that reportedly sickened more than 9,000, and seven died in a Canadian outbreak in 2000.
Kidney specialist Dr. Reinhard Brunkhorst, the president of the German Nephrology Society, told reporters in Hamburg that hospitals are now seeing fewer new infections reported each day, though cautioned that "it may be less, but it's not over yet."
"There is no reason for hysteria, because it's not spreading and it's not increasing - it's decreasing," he said.
Researcher Dag Harmsen at the Muenster University Hospital, which has been closely involved in the investigation of the outbreak, said that scientists were hoping to know enough about the E. coli strain by next week to be able to prevent new infections and better treat patients.
CBS News Medical Correspondent Dr. Jennifer Ashton said "disease detectives" are on the case, looking for the origins of the contamination and the pace of the spread.
"They're obviously trying to identify where the contamination came from and, medically, they're looking at the course that this illness is producing in human beings," she said.
However, Ashton said, beyond the theories about raw produce, there are still more questions than answers. Researchers say they've never seen anything like it.
The WHO recommends that to avoid food-borne illnesses, people wash their hands, keep raw meat separate from other foods, thoroughly cook their food, and wash fruits and vegetables, especially if eaten raw. Experts also recommend peeling raw fruits and vegetables if possible.
As the number of consumers avoiding vegetables grows, European farmers say they are losing millions of euros every day.
Russia on Thursday extended a ban on vegetables from Spain and Germany to the entire European Union to try to stop the outbreak spreading east, a move the EU quickly called disproportionate and
Italy's farmers denounced as "absurd." No deaths or infections have been reported in Russia.
Meanwhile, Chancellor Angela Merkel agreed with Spanish Prime Minister Jose Luis Rodriguez Zapatero in a telephone conversation late Thursday to push for EU help for affected farmers, Merkel's spokesman said.
Merkel, however, also defended the decision of state officials in Hamburg to announce their suspicions that Spanish cucumbers were the possible source of the outbreak. The warning was given after
three cucumbers from Spain tested positive for E. coli, but further tests then revealed that it was a different strain to the one that has sickened so many people in the northern port city and elsewhere.
"The chancellor indicated great understanding for the urgent economic situation in the Spanish produce sector," spokesman Steffen Seibert said.
"At the same time she noted the responsibility of the German agencies to keep citizens informed in all phases and to report test results to the European early warning system."
In the southern Spanish tourist resort town of Torremolinos, Spaniards handed out some 7 tons of cucumbers free to the public in a show of support for the farmers affected by the outbreak who have
seen their market collapse.