Leading article: We must be prepared for a new world of infection

The German outbreak of E.coli, caused by a rare and extremely virulent strain of the bug, is worrying on at least three counts.

First it has claimed the lives of 18 people and caused serious illness in 1,823 others, according to the World Health Organisation. That reminds us that bacteria are constantly mutating, new infections are just around the corner, and we are far from winning the fight against infectious disease in Europe. We must be vigilant and prepared, by stepping up monitoring and detection of disease and ensuring speedy and appropriate treatment for the victims in order to protect populations against the threat.

Second, the speed with which victims appeared in other countries – 12 had reported cases by yesterday from across Europe and including the US – reminds us that we live in a globalised world in which international travel is commonplace, bringing with it the threat of international transmission of infections. Mercifully there is no sign, so far, that the E.coli strain responsible for the outbreak in Germany has spread beyond its borders. But there is no possibility in the 21st century of countries bringing down the shutters and keeping bugs out.

Third, the German experience shows that it is necessary to act swiftly to save lives but not precipitately in a way that damages others. German chancellor Angela Merkel yesterday defended state officials in Hamburg, the centre of the outbreak, who initially warned Spanish cucumbers were the suspected source, before further tests revealed they carried the wrong strain of E.coli. Ms Merkel acknowledged the damage done to Spanish farmers by the announcement but insisted German authorities had a responsibility to "keep citizens informed in all phases" of their investigations.

Russia on the other hand has banned imports of vegetables from the entire European Union, in a move widely condemned as disproportionate. This is not an occasion for playing politics. The focus must be at all times on protecting lives.