Correspondence with Anja Siitonen

Correspondence with Anja Siitonen, KTL, Laboratory of Enteric Pathogens, National Public Health Institute, Helsinki, Finland.




The 1999 Alfalfa sprout outbreak of Salmonella Typhimurium PT193 in Finland raises some questions.  There was an outbreak in the US in January, 1999 of Clover sprouts.  I suspect that the outbreak in Finland was also clover.  Sprout growers mix clover with alfalfa because clover costs about half the price of alfalfa and is indistinguishable in the product.  Many growers call the product “Alfalfa” but list alfalfa and clover in the ingredients.  Most growers don’t mention that clover is in the package.  The FDA was not aware of this until 2004.


It would not help to know who the supplier or the lot number was, because the inspector would have listed the alfalfa seed lot and supplier, rather than the clover.  But do you know what month the outbreak occurred?


I appreciate your help.


Bob Rust



Dear Bob,

The outbreak occurred in May. The seeds were imported from Australia, but the food laboratory was not able to isolate the causative strain from the seeds or sprouts. The sprouts were revealed as a vehicle by the case – control study.

Your information of alfalfa/clover was very interesting.