Enterohaemorrhagic and other Shiga toxin-producingEscherichia coli(STEC): Where are we now regarding diagnostics and control strategies?

Abstract

Escherichia coli comprises a highly diverse group of Gram-negative bacteria and is a common member of the intestinal microflora of humans and animals. Generally, such colonization is asymptomatic; however, some E. coli strains have evolved to become pathogenic and thus cause clinical disease in susceptible hosts. One pathotype, the Shiga toxigenic E. coli (STEC) comprising strains expressing a Shiga-like toxin is an important foodborne pathogen. A subset of STEC are the enterohaemorrhagic E. coli (EHEC), which can cause serious human disease, including haemolytic uraemic syndrome (HUS). The diagnosis of EHEC infections and the surveillance of STEC in the food chain and the environment require accurate, cost-effective and timely tests. In this review, we describe and evaluate tests now in routine use, as well as upcoming test technologies for pathogen detection, including loop-mediated isothermal amplification (LAMP) and whole-genome sequencing (WGS). We have considered the need for improved diagnostic tools in current strategies for the control and prevention of these pathogens in humans, the food chain and the environment. We conclude that although significant progress has been made, STEC still remains an important zoonotic issue worldwide. Substantial reductions in the public health burden due to this infection will require a multipronged approach, including ongoing surveillance with high-resolution diagnostic techniques currently being developed and integrated into the routine investigations of public health laboratories. However, additional research requirements may be needed before such high-resolution diagnostic tools can be used to enable the development of appropriate interventions, such as vaccines and decontamination strategies.

Comparative Isolation of <i>Escherichia coli</i> 0157:H7 from Diarrhoeic and Non-Diarrhoeic Children in Selected Communities in Cross River State, Nigeria

“…In a study conducted by [21] in Edo State, Nigeria, a low prevalence of 2.7% was obtained from diarrhoeic patients. In Zahedan, Islamic Republic of Iran, [22] reported that out of 322 stool samples examined from children with diarrhoea, 21 colonies of sorbitol negative E. coli strains (6.5%) were isolated. Serotyping revealed 4 strains positive for E. coli O157: H7, out of which only 2 (0.6%) strains showed positive reaction with anti-H7 and were identified as E. coli O157:H7.…”

Síndrome Hemolítico Urémico asociado a Shigatoxina: ¿Cómo prevenirlo?

“…Se han descrito casos de portadores humanos sanos 7 . La ECEH resiste bastante bien las condiciones del medio ambiente natural -crece en forma óptima entre los 30 y 42°C-, tolerando incluso temperaturas de congelación y el pH ácido del estómago, pero se inac-tiva y destruye con temperaturas mayores a 68°C 8,9 . Su supervivencia alcanza hasta los 60 días en materia fecal y algunas cepas hasta 104 días en un medio acuático 10 .…”

“…Es necesario un buen lavado de manos con agua y jabón posterior a tocar animales u otras superficies cercanas a ellos, o antes de ingerir alimentos o líquidos en esos lugares. Se debiese realizar una adecuada limpieza de ropas y especialmente calzado posterior a estas visitas 6,8 . • Transmisión persona a persona.…”

“…En la actualidad se dispone de test de laboratorios rápidos en muestras de deposiciones, comercialmente disponibles, con variables grados de sensibilidad dada la corta duración de la STx en materia fecal 8 :…”

DISCONTOOLS supplement: Current research gaps for advancing control of infectious diseases in production animals

“…Consequently, risk reduction, primarily through consumer education and domestic hygiene training, remains of uttermost importance. Newell and La Ragione () describe current and future diagnostics and control strategies for Shiga toxigenic Escherichia coli (STEC). They argue that a substantial reduction in the public health burden due to this infection will require a multipronged approach, including ongoing surveillance with high‐resolution diagnostic techniques, integrated into routine investigations conducted by public health laboratories.…”