Epidemiology of Leptospirosis in Africa: A Systematic Review of a Neglected Zoonosis and a Paradigm for ‘One Health’ in Africa

Abstract

BackgroundLeptospirosis is an important but neglected bacterial zoonosis that has been largely overlooked in Africa. In this systematic review, we aimed to summarise and compare current knowledge of: (1) the geographic distribution, prevalence, incidence and diversity of acute human leptospirosis in Africa; and (2) the geographic distribution, host range, prevalence and diversity of Leptospira spp. infection in animal hosts in Africa.MethodsFollowing Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we searched for studies that described (1) acute human leptospirosis and (2) pathogenic Leptospira spp. infection in animals. We performed a literature search using eight international and regional databases for English and non-English articles published between January 1930 to October 2014 that met out pre-defined inclusion criteria and strict case definitions.Results and DiscussionWe identified 97 studies that described acute human leptospirosis (n = 46) or animal Leptospira infection (n = 51) in 26 African countries. The prevalence of acute human leptospirosis ranged from 2 3% to 19 8% (n = 11) in hospital patients with febrile illness. Incidence estimates were largely restricted to the Indian Ocean islands (3 to 101 cases per 100,000 per year (n = 6)). Data from Tanzania indicate that human disease incidence is also high in mainland Africa (75 to 102 cases per 100,000 per year). Three major species (Leptospira borgpetersenii, L. interrogans and L. kirschneri) are predominant in reports from Africa and isolates from a diverse range of serogroups have been reported in human and animal infections. Cattle appear to be important hosts of a large number of Leptospira serogroups in Africa, but few data are available to allow comparison of Leptospira infection in linked human and animal populations. We advocate a ‘One Health’ approach to promote multidisciplinary research efforts to improve understanding of the animal to human transmission of leptospirosis on the African continent.

Molecular epidemiology of pathogenic <i>Leptospira</i> spp. among large ruminants in the Philippines

“…Although the majority of our samples came from water buffalo and the molecular analysis was limited, our findings may further support the previous reports regarding the diversification of Leptospira species [8, 17, 34], wherein this phenomenon can be attributed to maintenance of host animals (alteration of physiology or immune system) or environmental factors [14, 17]. L. borgpetersenii is known to have a broad host range [2, 17] and is restricted to animal-to-animal transmission [5], and therefore is more prone to diversification. A wider study coverage area along with the use of recent molecular typing methods, such as multiple-locus variable-number of tandem repeat analysis and multilocus sequence typing, should be employed in future studies to reveal the genetic diversity of Leptospira present in large ruminants in the Philippines.…”

“…L. kirschneri was found in water buffalo farms in this study. Previous studies have reported its presence in cattle in Africa [2], Sri Lanka [13] and Brazil [4] and were one of the predominant Leptospira species linked to human disease and animal infection [2]. …”

Utility of a modified silver staining technique for detection of Leptospira

“…1,2 Leptospirosis is endemic in Sri Lanka with outbreaks of disease generally associated with the paddy cultivation seasons and monsoon periods. Many mammalian species can harbor leptospires in their kidneys and act as reservoirs for transmission of infection.…”

Leptospirosis and Extensive Urbanization in West Africa: A Neglected and Underestimated Threat?

“…Additional focus should be made on the African continent where data on leptospirosis are scarce (reviewed in [17,18]) compared to other continents [3]. In parts of Africa, health services may be poorly developed with limited treatment and diagnostic testing capacities.…”

“…circulating in Benin, Ghana, Ivory Coast and Nigeria, but, to our knowledge, no studies have been performed in Togo (reviewed in [17,18]). …”