Berlin: German authorities conducted tests Monday on locally-grown sprouts suspected of being the source of an E. coli outbreak which has killed 22 and left some 2,000 ill across Europe.
Gert Lindermann, agriculture minister in the northern state of Lower-Saxony, announced on Sunday that a link had been found between a small farm producing a variety of sprouts and "all the main outbreaks" of the disease in the country.
But federal Health Minister Daniel Bahr and the Robert Koch Institute, Germany`s main health institute, warned against rushing to judgement.
"For the time being we are careful not to rush to premature judgements," Bahr said on television.
Germany last week was strongly criticized by Spain`s government after officials in Hamburg warned the outbreak might be linked to cucumbers imported from Spain.
"We have clear indications that a farm in the district of Uelzen is a likely source of the contamination, but we must first wait for the results of the laboratory tests," Bahr added.
Andreas Hensel, head of Germany`s federal Risk Assessment Institute, said that "we can`t be sure that the sprouts are responsible".
News of the possible breakthrough came about a month after people were first infected in northern Germany.
The outbreak, which has spread to a dozen other European countries, has caused chaos among Europe`s vegetable growers after Germany warned against eating raw cucumbers, tomatoes or lettuce.
The death toll has climbed to 22, according to latest figures by the European Centre for Disease Prevention and Control.
All but one of the deaths occurred in Germany. The other was in Sweden.
Initial tests from a farm producing the sprouts showed contamination by the bacteria, Lindermann told a news conference.
Sprouts cultivated there include those from lettuce, azuki beans, mung beans, fenugreek, alfafa and lentils. Some of the seeds had been imported from abroad.
"It is significant that two women employees from the firm are ill with diarrhoea, and in one case EHEC (a strain of E. coli) has been diagnosed," Lindermann said.
Early indications are that the farm "is at least one of the sources of contamination," he added.
The sprouts grow in temperatures of 37 degrees celsius (around 98 degrees Fahrenheit) "which is ideal for all bacteria," the minister said.
The farm is in the village of Bienenbuettel, some 80 kilometres (50 miles) south of Hamburg, one of the main cities hit by the outbreak.
Authorities in Lower-Saxony said the sprouts were delivered, either directly or through wholesalers, to restaurants in Hamburg, Schleswig-Holstein, Mecklenburg-Pomerania, Hessen and Lower-Saxony itself.
Further test results were expected to be announced on Monday or Tuesday.
The European Commission meanwhile said it had not formally been notified of the development.
"The German authorities simply said on Sunday they were going to circulate the information about their suspicions surrounding a sprout-producing firm on the rapid alert system system for food," said spokesman Federic Vincent.
Bahr, who on Sunday visited Hamburg`s Eppendorf University clinic where many patients are being treated, has warned the source could still be active.
"Food health officials are working around the clock to identify the source of the infection," Bahr said.
"But from earlier outbreaks, we know that we can`t always identify the source.
"It can`t be ruled out that the source of infection is still active," he added, calling for continued vigilance as authorities still counsel against eating raw tomatoes, lettuce and cucumbers.
Bahr said also the situation in a number of hospitals, especially Hamburg and Bremen, was "difficult" because of the high number of admissions.
E. coli cases have also been reported in around a dozen countries, including Britain, France, Spain, Sweden and the United States. Each was related to German travel.
The World Health Organisation has identified the bacteria as a rare E. coli strain never before connected to a food poisoning outbreak. It is said to be extremely aggressive and resistant to antibiotics.