Haemoglobin and red cell counts in leptospirosis patients infected with different serovars

Introduction The aim of the study was to compare haemoglobin and red cell counts between patients known to be infected with a range of leptospiral serovars. Methods The study retrospectively compared the haemoglobin and red cell count results from the first blood samples taken from 207 patients at presentation to a Queensland Health hospital. Results Significant differences were observed in haemoglobin and red cell counts in those infected with Leptospira interrogans serovars Szwajizak and Canicola when compared with most of the other serovars. Conclusions These findings suggest that haemoglobin and red cell counts may be useful in differentiating leptospiral serovars in leptospirosis patients. .

Survey of leptospirosis of small mammals in Thailand.

During 1999-2000, kidney tissues of approximately 15% of 1310 rodents trapped from northeastern provinces of Thailand were tested for the presence of leptospires. Our direct immunofluorescent assay (DFA) for detection of leptospires showed 100% sensitivity and 94% specificity with the culture data. Both methods identified R. norvegicus as the highest source of infection. Among isolated Leptospira, 137 were serotyped by cross agglutinin absorption and/or a microscopic agglutination, and gave some variations and similarities at the serovar level to the DFA results. DFA data demonstrated over half of the positive animals were infected with several serovars of Leptospira interrogans. A subsequent DFA study in Bangkok in 2002 revealed leptospiral infection in 33% of 42 rats and shrews. The most common infecting serovars were Autumnalis and Canicola identified in rural and urban animals, respectively. This finding suggests that wild small mammals may act as important sources of pathogenic leptospires and warrant active surveillance to understand the epidemiology of transmission and control of carrier animals.