Seroprevalence of Leptospirosis among High-Risk Individuals in Morocco

Mohamed El Azhari (1) , Mathieu Picardeau (2) , Imad Cherkaoui (3) , Mohamed Anouar Sadat (4) , Houda Moumni (3) , Kamal Marhoum El Filali (5) , Hassan Ghazal (6) , Abderrahmane Maaroufi (3) , Salsabil Hamdi (1) , Naima El Mdaghri (1) , Pascale Bourhy (2)

1 Institut Pasteur du Maroc
2 CNR - Centre National de Référence des Leptospires
3 Epidemiology and Disease Control [Casablanca]
4 Health Delegation of Mediouna
5 CHU Ibn Rochd [Casablanca]
6 National Center for Scientific and Technological Research [Rabat]

Background: Leptospirosis is an anthropozoonotic reemerging neglected infectious disease underreported in most developing countries. A cross-sectional study was performed between 17 and 23 February 2014 to estimate the seroprevalence of leptospirosis among high-risk populations in Casablanca (Morocco). Methods: A total of 490 human serum samples (97.6% males) were collected in 3 high-risk occupational sites including the biggest meat slaughterhouse (n = 208), a poultry market (n = 121), and the fish market (n = 161). A total of 125 human blood samples were also collected from the general population and used in this study as a control group. To detect the presence of anti-Leptospira, sera were screened with in-house IgG and IgM enzyme-linked immunosorbent assay (ELISA). Positive samples were tested by Microscopic Agglutination Technique (MAT) using a panel of 24 serovar cultures and cut point of 1 : 25. Results: Seroprevalence of leptospirosis among the control group was 10.4% (13/125). A high seropositivity among the overall seroprevalence of 24.1% (118/490) was observed in the high-risk groups of which 7.3% (36/490), 13.7% (67/490), and 3.1% (15/490) were for anti-Leptospira IgM, IgG, and both IgG and IgM antibodies, respectively. Most of the positive individuals were occupationally involved in poultry (37.2%), followed by the market fish (26.1%) and the meat slaughterhouse (14.9%) workers. Among all ELISA-positive serum samples, 20.3% (n = 24) had positive MAT responses, of which the Icterohaemorrhagiae (n = 7) is the most common infecting serogroup followed by Javanica (4), Australis (2), and Sejroe, Mini, and Panama (one in each). In the remaining 8 MAT-positive sera, MAT showed equal titers against more than one serogroup. Conclusion: Individuals engaged in risk activities are often exposed to leptospiral infection. Therefore, control and prevention policies toward these populations are necessary.

Domains: Life Sciences [q-bio]; Microbiology and Parasitology

Mohamed El Azhari, Mathieu Picardeau, Imad Cherkaoui, Mohamed Anouar Sadat, Houda Moumni, et al.. Seroprevalence of Leptospirosis among High-Risk Individuals in Morocco. Interdisciplinary Perspectives on Infectious Diseases, 2020, 2020, pp.5236045. ⟨10.1155/2020/5236045⟩. ⟨pasteur-02939008⟩