Carriage of Leptospira interrogans among domestic rats from an urban setting highly endemic for leptospirosis in Brazil

• Published in: Acta tropica Vol. 108; no. 1; pp. 1 - 5
• Main Authors: Faria, Marcos Tucunduva de, Calderwood, Michael S., Athanazio, Daniel A., McBride, Alan J.A., Hartskeerl, Rudy A., Pereira, Martha Maria, Ko, Albert I., Reis, Mitermayer G.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.10.2008; Elsevier
• Subjects: Agglutination Tests; Animals; Bacterial diseases; Bacterial Typing Techniques; Biological and medical sciences; Blood - microbiology; Brazil; Carrier State - epidemiology; Carrier State - microbiology; Carrier State - veterinary; Didelphis - microbiology; Didelphis marsupialis; Disease Reservoirs; General aspects; Human bacterial diseases; Infectious diseases; Kidney - microbiology; Leptospira; Leptospira interrogans; Leptospira interrogans - classification; Leptospira interrogans - isolation & purification; Leptospirosis; Leptospirosis - epidemiology; Leptospirosis - transmission; Leptospirosis - veterinary; Medical sciences; Miscellaneous; Poverty areas; Rats; Rats - microbiology; Rattus; Rattus norvegicus; Serotyping; Urban Health; Urine - microbiology; South America; Brazil; America; Leptospirosis; Rats; Poverty areas; Leptospira; Urban environment; Poverty; Socioeconomic status; Spirochaetales; Rat; Rodentia; Epidemiology; Infection; Vertebrata; Mammalia; Spirochaetosis; Animal; Leptospiraceae; Bacteriosis; Bacteria; Tropical medicine; Leptospira interrogans; Colonization
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2008.07.005

A survey was conducted to identify reservoirs for urban leptospirosis in the city of Salvador, Brazil. Sampling protocols were performed in the vicinity of households of severe leptospirosis cases identified during active hospital-based surveillance. Among a total of 142 captured Rattus norvegicus (Norwegian brown rat), 80.3% had a positive culture isolate from urine or kidney specimens and 68.1% had a positive serum sample by microscopic agglutination test (MAT) titre of ≥1:100. Monoclonal antibody-based typing of isolates identified that the agent carried by rats was Leptospira interrogans serovar Copenhageni, which was the same serovar isolated from patients during hospital-based surveillance. Leptospira spp. were not isolated from 8 captured Didelphis marsupialis (Opossum), while 5/7 had a positive MAT titre against a saprophytic serogroup. R. rattus were not captured during the survey. The study findings indicate that the brown rat is a major rodent reservoir for leptospirosis in this urban setting. Furthermore, the high carriage rates of L. interrogans serovar Copenhageni in captured rats suggest that there is a significant degree of environmental contamination with this agent in the household environment of high risk areas, which in turn is a cause of transmission during urban epidemics.