The occurrence of campylobacters in water sources in South Africa

Abstract

Campylobacter spp., mainly C. jejuni and C. coli, are recognized as significant human bacterial pathogens, being responsible for increasing numbers of gastroenteritis cases worldwide. Several reports have indicated that environmental waters are potential reservoirs and transmitting vehicles for these bacteria. The purpose of this study was thus to examine the occurrence of campylobacters in drinking and environmental water sources of South Africa, a country with a warmer climate and higher microbial pollution levels than those previously addressed in the Northern Hemisphere where similar investigations have been undertaken. Various types of water samples (five drinking water, four ground water, 11 surface water and four raw sewage) were collected from different parts of South Africa. Detection was by enrichment in Bolton broth prior to plating on both selective mCCDA or through a 0.6microm membrane filter on non-selective blood agar isolation media. Out of 100 initially selected Campylobacter-like isolates, only 22 did not grow aerobically and were subsequently identified as Campylobacter spp. by biochemical tests. However, the results obtained by 16S rRNA sequence analysis indicated that only three of these strains (13.6%) were Campylobacter jejuni and the remaining 19 strains were identified as Arcobacter butzleri. The spread of Arcobacter via water warrants further investigation, especially in view of the higher levels of detection and pathogenic nature of these bacteria.