Pfeiffer Reaction and Protection Tests in Leptospiral Jaundice (Weil's Disease) with Leptospira Icterohaemorrhagiae and Leptospira Icteroides
Andrew Watson Sellards AND
Max Theiler
From the Department of Tropical Medicine, Harvard Medical School, Boston, Massachusetts
1. The serum of 5 patients and 1 guinea pig after recovery fromleptospiral jaundice (Weil's disease) gave positive Pfeifferreactions and protected guinea pigs against L. icterohaemorrhagiaeand L. icteroides.
2. A series of titrations showed that these6 immune sera wereessentially equal in their effects againstthese 2 strains ofleptospira.
3. From an etiological standpointL. icteroides is a synonymof L. icterohaemorrhagiae.
4. Ifthe serum of a patient convalescent from an attack ofacuteinfectious jaundice gives positive Pfeiffer reactionswith protectionof guinea pigs against either L. icterohaemorrhagiaeor L. icteroides,the diagnosis of leptospiral jaundice (Weil'sdisease) is justified.Negative reactions are consistent withthe diagnosis of yellowfever.