Vibrio cholerae Incursion in Africa, the Journey So Far

Abstract

Indeed, a host of the plenty of reports about pathogenic Vibrios, have been from African researchers. And they assert that this severe diarrhea causing agent originated from Asia thousands of years ago and spread (first, via the sea route) affecting particularly the coastal towns and fishing villages, before moving to other parts of the world. Following the primary cholera outbreak of 1868, Vibrio cholera, appeared in the Atlantic coast of West Africa. The pathogen then invaded African countries chronologically beginning with Guinea, then Sierra Leone, Liberia, Cote d’ivoire, Mali, Togo, Dahomey, Upper Volt (Burki Na-faso) and finally Nigeria (Lagos) and Niger in December, 1970. Various serogroups (O139 and O1 with biotypes Classical and El Tor) and Serotypes of O1 (Ogawa, Inaba and Hikojima) and recently, the O395 strain have been reported; especially from outbreaks reported from hotspots that are close to riverine areas. This suggests that these emergent pathogenic species originate from around water environments probably from the non-pathogenic strains. This condition is likely harnessed by Lateral Gene Transfer (LGT), which is seen to occur usually between pandemic V. cholerae and environmental strains; a situation that may result in the creation of new pandemic strains. Therefore, in order to better understand and appreciate the evolution of the Vibrio cholerae strains that are involved in epidemics, and the relationship between the species causing particular epidemics in different regions of Africa, a study of the molecular picture of the environmental strains and the mechanisms by which the pathogenic Vibrio cholera strains appear and diffuse from these strains is necessary. This review seeks to trace the origin and spread route of Vibrio cholerae strains causing epidemics in different regions of the African continent (Nigeria in particular) with the aim of establishing relationships between the strains causing epidemics in these regions. This will help in the development of better intervention strategies to contain the disease.