Application of pyrolysis mass spectrometry to the investigation of outbreaks of food poisoning and non-gastrointestinal infection associated with Bacillus species and Clostridium perfringens.

Eighteen isolates of Bacillus species and 15 of Clostridium perfringens, all of which had been associated with outbreaks of either food poisoning or non-gastrointestinal infection (NGI), were examined for relatedness by pyrolysis mass spectrometry (PyMS). The PyMS-analysis correctly clustered all the groups of epidemiologically related isolates of both genera, and distinguished all the single, epidemiologically unrelated isolates of the same species. PyMS is a simple, rapid and inexpensive technique which can provide useful and accurate inter-strain comparisons within both the Bacillus and Clostridium genera in complete accord with conventional serological typing results.