An accidental laboratory infection with African trypanosomes of a defined stock I. The clinical course of the infection

Summary The case history and successful treatment of a patient accidentally infected with Trypanosoma brucei rhodesiense in a Scottish laboratory are reported. As the experimental use of trypanosomes is increasing it seems probable that other accidents may occur in the laboratory. Preparations that might be made in anticipation of these are suggested. The accidental infection provided the opportunity for an investigation which led to the discovery that only one of the variable antigen types derived from this stock was infective for man after passage in rodents. This valuable piece of epidemiological information might not have been discovered in any other way. The aetiologically important variable antigen type involved is one of a group or ‘serodeme' which has been accurately defined immunologically and it is likely that this is the first case of an accidental infection with trypanosomes from a well defined stock, although this serodeme and others are held in many laboratories.