Leptospirosis Prevalence and Risk Factors Among Patients Presenting With Fever to 4 Healthcare Sites in Sub-Saharan Africa and South East Asia: An International Multisite Observational and Nested Case–Control Study
Crump JA., Mogeni P., Ajanovic SA., Bramugy JM., Chimenya M., Green EW., Lal S., Mabey DCW., Mayxay M., Newton PN., Olaru ID., Hopkins H., Picardeau M., Amos B., Ashley EA., Baerenbold O., Baghoumina S., Balanza N., Bandason T., Bassat Q., Bhattacharyya T., Blacksell SD., Boca Z., Bottomley C., Bradley J., Chandler CIR., Chansamouth V., Chipanga J., Cossa A., Dauya E., Davis C., Dixon J., Douangphachanh S., Dubot-Pérès A., Durkin MM., Feasey NA., Ferrand RA., Fink C., Fitchett EJA., Gerada A., Graves SR., Handley BL., Hutchison CD., Jaksuwan R., Jervis J., Jones J., Kain KC., Keddie SH., Khounpaseuth K., Kranzer K., Kunlaya K., Lal P., de Lamballerie X., Lalloo DG., Luangraj M., Lubell Y., MacPherson E., Manichan S., Marlais T., Maurer F., Miles M., Mucasse C., Nguyen C., Phimolsarnnousith V., Roberts CH., Sengduangphachanh A., Sengsavang S., Sibanda M., Singha S., Stenos J., Tanganuchitcharnchai A., Tanvir H., Ussher JE., Valente M., Voice MA., Vongsouvath M., Wamaka M., Wheat LJ., Yeung S.
Abstract Background We investigated the prevalence, diversity, and risk factors for acute leptospirosis in the Febrile Illness Evaluation in a Broad Range of Endemicities (FIEBRE) study. Methods Febrile patients aged ≥2 months in Laos, Malawi, Mozambique, and Zimbabwe underwent a standardized clinical and exposure assessment. Acute and convalescent serum were tested by Leptospira microscopic agglutination test (MAT) and acute plasma by lfb1 polymerase chain reaction. A ≥4-fold rise in antibody titer, or a single reciprocal titer ≥800, or Leptospira PCR positive defined confirmed leptospirosis. The identity of possible infecting strains was investigated by MAT and sequencing of PCR products. Results Of 7851 febrile participants enrolled, 134 (1.7%) had confirmed leptospirosis: 88 (4.6%) in Laos, 17 (1.0%) Malawi, 7 (0.3%) Mozambique, and 22 (1.2%) Zimbabwe, and 23 (0.8%) had supportive evidence of leptospirosis. Participants with leptospirosis had greater odds of headache (adjusted odds ratio [aOR] 2.20, P < .001), rash (aOR 1.45, P < .001), conjunctivitis (aOR 3.33, P < .001), and jaundice (aOR 1.75, P < .001); and had greater odds of being older (aOR 1.02 per year, P < .001), working in rice fields (aOR 6.24, P < .001), drinking river water (aOR 5.11, P = .001). Predominant reactive Leptospira serogroups were Ballum and Icterohemorrhagiae at African sites, and Australis in Laos. Identified species were Leptospira borgpetersenii, L. interrogans, and L. kirschneri. Conclusions Leptospirosis was a cause of febrile illness at all sites. Some clinical features helped to identify patients with leptospirosis. Interventions related to rice field work and river exposure may prevent disease. Diverse Leptospira serogroup reactivity was observed and may suggest potential hosts.