In September 2018, Hurricane Florence caused extreme flooding in eastern North Carolina, USA, a region highly dense in concentrated animal production, especially swine and poultry. In this study, floodwater samples (n=96) were collected as promptly post-hurricane as possible and for up to approx. 30 days, and selectively enriched for Campylobacter using Bolton broth enrichment and isolation on mCCDA microaerobically at 42°C. Only one sample yielded Campylobacter, which was found to be Campylobacter jejuni with the novel genotype ST-2866. However, the methods employed to isolate Campylobacter readily yielded Arcobacter from 73.5% of the floodwater samples. The Arcobacter isolates failed to grow on Mueller-Hinton agar at 25, 30, 37 or 42°C microaerobically or aerobically, but could be readily subcultured on mCCDA at 42°C microaerobically. Multilocus sequence typing of 112 isolates indicated that all were Arcobacter butzleri. The majority (85.7%) of the isolates exhibited novel sequence types (STs), with 66 novel STs identified. Several STs, including certain novel ones, were detected in diverse waterbody types (channel, isolated ephemeral pools, floodplain) and from multiple watersheds, suggesting the potential for regionally-dominant strains. The genotypes were clearly partitioned into two major clades, one with high representation of human and ruminant isolates and another with an abundance of swine and poultry isolates. Surveillance of environmental waters and food animal production systems in this animal agriculture-dense region is needed to assess potential regional prevalence and temporal stability of the observed A. butzleri strains, as well as their potential association with specific types of food animal production.

Access the full publication.

This work was supported by the IAFNS Food Microbiology Committee.