Via BBC News: E. coli outbreak in Germany: Women more affected. Excerpt:
One of the mysteries about the outbreak of the particularly vicious strain of E. coli is that most of the victims have been women.
In most outbreaks, the victims are children because they have not developed the immune system to fight off the food poisoning - but in the German case, it is adults and female adults, in particular.
Scientists simply do not know why.
One theory was that the victims were often people who liked eating what they thought was healthy food, say because it was low calorie (like cucumbers) or because it was organic.
But the scientists are now cautioning against that view. It may be too pat.
Dr Ulf Goebel of the Charite university hospital in Berlin said it might just be that this specific strain had something in it which found women's bodies suitable and not men's (just as some strains work on some ethnic groups and not others).
Intriguingly, a previous outbreak of this rare type of E. coli happened in the United States in 1994 - and again the victims were predominantly women, with the average victim being 36 years of age.