Search for Campylobacter spp. Reveals High Prevalence and Pronounced Genetic Diversity of Arcobacter butzleri in Floodwater Samples Associated with Hurricane Florence in North Carolina, USA

Abstract

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. IMPORTANCE Climate change and associated extreme weather events can have massive impacts on the prevalence of microbial pathogens in floodwaters. However, limited data are available on foodborne zoonotic pathogens such as Campylobacter or Arcobacter in hurricane-associated floodwaters in rural regions with intensive animal production. With high density of intensive animal production as well as pronounced vulnerability to hurricanes, Eastern North Carolina presents unique opportunities in this regard. Our findings revealed widespread incidence of the emerging zoonotic pathogen Arcobacter butzleri in floodwaters from Hurricane Florence. We encountered high and largely unexplored diversity while also noting the potential for regionally-abundant and persistent clones. We noted pronounced partitioning of the floodwater genotypes in two source-associated clades. The data will contribute to elucidating the poorly-understood ecology of this emerging pathogen, and highlight the importance of surveillance of floodwaters associated with hurricanes and other extreme weather events for Arcobacter and other zoonotic pathogens.

The Persistence of Bacterial Pathogens in Surface Water and Its Impact on Global Food Safety

“…As seen with Campylobacter, human pathogenic Arcobacter species have been isolated from sewage, wastewater (before and after treatment), waterbodies such as lake, river, spring and drinking water samples including groundwater [140,142,143,151,152]. More recently, Arcobacter butzleri was isolated from floodwaters after hurricane Florence in North Carolina, close to a region of swine and poultry production [153].…”

“…Additionally, a higher association of campylobacteriosis was observed with increased rainfall in various regions of Ontario and Québec [118,121,158]. Similarly, extreme precipitation and a hurricane have resulted in contamination of water with Arcobacter on the South Bass island in Ohio and North Carolina, respectively [138,153]. The importance of water as a reservoir of Arcobacter is further suggested by their ability to survive for extended periods of time at various temperatures [142,159].…”

“…Currently, there are no standard methods for the detection of Arcobacter in water. Further, while Arcobacter species are aerotolerant, conventional methods used for the isolation of microaerophilic Campylobacter can also enrich Arcobacter species [153]. Researchers from different countries have developed culture and molecular methods for the isolation and characterization of Arcobacter spp.…”

Coastal Microbial Communities Disrupted During the 2018 Hurricane Season in Outer Banks, North Carolina

“…Eastern North Carolina also exhibits high concentrations of agricultural and animal production that have serious coastal ecosystem consequences as a result of storm-induced floodwaters and runoff ( Mallin and Cahoon, 2003 ; Casteel et al, 2006 ). Increased relative abundance of foodborne zoonotic pathogens due to Hurricane Florence has been reported for watersheds of North Carolina ( Niedermeyer et al, 2020 ). It is important to understand the impact of environmental fluctuations on coastal North Carolina microbial communities and its subsequent influence on steady-state conditions, resistance and resiliency, and future climate change scenarios for this ecosystem.…”

Prevalence, antimicrobial susceptibility and virulence gene profiles of Arcobacter species isolated from human stool samples, foods of animal origin, ready-to-eat salad mixes and environmental water

“…Arcobacter spp. have been isolated from various sources: farm environment, animals, vegetables and food products of animal origin (at the processing stage and retail), food-processing facilities, environmental waters, sewage and oodwater [8][9][10][11]. Consumption of contaminated food of animal origin (meat, milk, seafood), vegetables or water is considered as the main route of transmission to humans [6].…”