To the Editor:

The study of Wolf and colleagues, published in Journal of Travel Medicine 2005; 12:343–346, was examining whether people on antimalarials can have secondary gain from protection against typhoid and Shigella infections.

There seems to be an area of confusion in this paper. Salmonella typhimurium does not cause typhoid. Salmonella typhi does.

The authors might have been studying S typhimurium for perfectly good reasons, but in my view it is wrong and misleading to claim that an effect on S typhimurium has anything to do with typhoid.