The World Health Organization (WHO) says the strain of E.coli that has caused deaths in Germany has never been seen in an outbreak of illness before.
A spokeswoman in Geneva said that the WHO was waiting for more information from laboratories.
Chinese scientists at the Beijing Genomics Institute in Shenzhen city, who have newly analysed the genes of the strain, said it carried genes which made it resistant to some classes of antibiotics and was highly toxic.
The scientists in Beijing, who are collaborating with Germany's University Medical Center Hamburg-Eppendorf, completed sequencing the genome of the bacterium in three days after receiving DNA samples.
The German medical centre treated many of the infected patients from north Germany and found they did not respond to some of the antibiotics used, the Chinese scientists said.
Authorities are still hunting for the source of the new bacteria, which is believed to have contaminated raw vegetables. The E.coli outbreak has so far killed at least 17 people and made more than 1,500 others ill in eight European countries, including two in Switzerland.
The Swiss Federal Health Office said on its website that there was no big risk to Switzerland at present.
swissinfo.ch and agencies