Seroepidemiology of Leptospirosis among febrile patients in a rapidly growing suburban slum and a flood vulnerable rural district in Mozambique, 2012-2014: Implication for the management of fever.

Leptospirosis, is one of most widespread zoonosis in the world and is caused by spirochetes of the genus Leptospira. In Mozambique, the disease is heavily ignored and its epidemiology is unknown. The objective of this study was to investigate occurrence of leptospirosis in febrile patients.A cross-sectional study was conducted among febrile patients between June 2012 and September 2015. A total of 373 paired samples were drawn from febrile patients, of whom 208 were from Caia District Hospital (rural setting) in Sofala province and 165 were from Polana Caniço General Hospital (suburban setting) in Maputo city. Samples were initially screened using an in-house ELISA for IgM and IgG antibodies. Double positive samples were confirmed using MAT.Of the 373 febrile patients, 5 (1.3%) had acute leptospirosis (MAT ≥400) and 38 (10.2%) had presumptive infection [IgM(+)/MAT≥100&MAT <400]. While most of the patients with presumptive infection (84.2%; 32/38) lived in rural settings, 60% (3/5) and 60.3% (199/330) of the patients with acute infections and negative results lived in the sub-urban setting (p=0.000). Contact with rodents was significantly higher (p=0.031) in patient with acute leptospirosis (100%; 5/5), as compared to those with presumptive infection (39.5%; 15/38) and negative results (41.8%; 138/330). A total of 4 out of 5 patients (80%) with acute leptospirosis were treated with antimalarial drugs although malaria results were negative. The most prevailing serogroup, according to MAT results, was Australis (40%; 4/10), followed by Icterohaemorrhagiae (30%; 3/10).This study demonstrates that leptospirosis is prevalent among Mozambicans, and most of cases are misdiagnosed as malaria.