Prevalence of<i>E. coli</i>O157:H7 strains in irrigation water and agricultural soil in two district municipalities in South Africa
Chidozie Declan Iwu, Erika M. du Plessis, Lisé Korsten, Anthony I. Okoh
Abstract
We assessed the prevalence of E. coli O157:H7 in irrigation water and agricultural soil samples in two District Municipalities in South Africa using standard culture-based and molecular techniques. Presumptive E. coli O157:H7 counts in irrigation water and agricultural soil samples ranged from 1.00 Log10 CFU/100 ml to 4.11 Log10 CFU/100 ml and 2.20 Log10 CFU/g to 4.21 Log10 CFU/g respectively (P ≤ 0.05). Thirteen (28%) of the confirmed isolates (n = 46) were Shiga toxigenic and 33 (72%) were Shiga toxin negative. The presence of Shiga toxigenic E. coli O157:H7 strain in irrigation water and agricultural soil samples reported by this study suggests potential risk to food safety and population health.