Molecular detection of enterotoxigenic escherichia coli surface antigens from patients in Machakos district hospital, Kenya

Abstract

Introduction: Enterotoxigenic Escherichia coli (ETEC) is known for its public health importance globally, however, a protective vaccine is yet to be developed. Information regarding the immunology of ETEC’s virulence proteins that can lead to studies on vaccine development such as the heat stable toxins (ST), heat-labile toxin (LT), colonization factors (CFs) and coli surface antigens (CS) from many regions of the world is available. In Kenya, specific CFAs and CS have not been adequately characterized. This study looked at the surface antigens of diarrhoeagenic E. coli in search of indicators for vaccine materials development. Methodology: Multiplex polymerase chain reaction assay were employed to detect diarrhoeagenic E. coli pathotypes and enteroxigenic Escherichia coli surface antigens/ colonization factors antigens from 300 patients in Machakos Hospital, Kenya. Results: Enteroaggrigative Escherichia coli was the most predominant (13.7%) followed by ETEC (11%), Enteroinvesive E. coli (8.3%) and Enteropathogenic E. coli (4.3%). Among the colonization factor antigens, CFAI was detected at 25 (23%), CS1, CSII 2(1.9%), CS3 1(0.9%), CS6 13(12%), CS7 2 (1.9%), CS12 1(0.9%), CS19 11 (10.25%) and those without colonization factor 37 (34.3%). Conclusions: ETEC isolates carrying ST or STLT toxins had more recoverable CFs than those with LT alone (P<0.05). The CS6 is increasing and CS19 was detected for the first time in Kenya and shown to be persistent adhesins. These may be further investigated as possible candidates for the formulation of a novel vaccine for the prevention of diarrhoea in Kenya and the region