Isolation and antibiotic profile ofVibriospp. in final effluents of two wastewater treatment plants in the Eastern Cape of South Africa

Abstract

Background: Poorly or partially treated wastewater disposed of can contaminate water and even properly treated sewage can have its problems. The highlight of this danger is wastewater treatment plants serving as reservoir for proliferation of antibiotic resistant organisms. We have reported the state of two wastewater treatment in the Eastern Cape of South Africa which discharge poorly and partially treated effluents. Our aims to identify Vibrio spp. and their antibiotic profiles in treated final effluent discharge from wastewater treatment plant.Methods: Culture based approach using the TCBS agar for isolation Vibrio spp., presumptive isolates were purified and confirmed using PCR. The confirmed isolated were also genotyped to identify the species present. The antibiotic profiling of the confirmed isolates was using the CLSI recommended first line antibiotics for Vibrio. Results:Out of the 786 presumptive isolates, 374 were confirmed as Vibrio spp. None of the Vibrio spp. pathotypes were present in the confirmed isolates. Randomized isolates of 100 Vibrio spp. were selected, > 90 % of the isolates were susceptible to Ciprofloxacin, and > 50 -80 % for Ampicillin, Chloramphenicol, Tetracycline, Cefotaxime, and Trimethoprim-sulfamethoxazole respectively. Conclusions:We are able to isolate Vibrio spp. from treated effluents but none of their pathotypes were present. The antibiotic agents considered for primary testing which are ciprofloxacin was the most effective of the antibiotic drugs, followed by cefotaxime, tetracycline with less susceptibility. Contamination from discharged effluents from wastewater treatment can lead to spread of spread of disease in this environment. The WWTPs studied are sources of pollution to surface water with environmental and public health. Phenotypic identification of VibrioConsidering the salt tolerance of some Vibrio spp., can grow at a salt concentration of 3% NaCl [36]. Presumptive isolates from the TCBS culture plates were inoculated into a tube each of 1% tryptone broth (TSB) with 2% NaCl and incubated 18-24 h at 35-37 °C. Profuse growths in tubes are considered as positive. Various species have different salt tolerance that can be used for identification. This test helps to eliminate presumptive colonies from the TCBS plate which resemble Vibrio, e.g. Proteus [37,38]. Isolation of genomic DNA and Genotypic identification of VibrioVibrio isolates from the freeze storage were inoculated on TSB broth overnight for crude DNA extraction. Frozen cells were kept on ice to reduce thawing by scraping the ice surface with a loop. ZR Fungal/Bacterial DNA MiniPrep by Zymo Research was used to extract genomic DNA following the manufacturer's instruction. The genomic extracts were immediately used in the molecular identification of the isolated organisms. Primers specific for the confirmation of the Vibrio isolates was used in the polymerase chain reaction. PCR amplification was performed with a MyCycler thermal cycler PCR (Bio-Rad). The PCR solution contained 2 x PCR mastermix, 100uM each o...

Antibiogram signatures of non-cholera causing Vibrio species recovered from environmental niches in Eastern Cape, South Africa.

“…Twenty-nine percent of the Vibrio isolates exhibited resistance against tetracycline, while 71 % of the isolates were susceptible against tetracycline. This report corroborates with the reports of Quilici et al [33]; Raissy et al [35]; Osuolale and Okoh, [32].…”

Aquatic environments: A potential source of antimicrobial-resistant Vibrio spp.

“…associated with poorly treated effluent water have caused Vibrio epidemics in various countries (e.g. Haiti, Kenya and South Sudan) (Osuolale & Okoh, 2018). Vibrio spp.…”

“…isolates were positive for the catIV gene. A study done by Osuolale and Okoh (2018) reported that 21.5% of Vibrio spp. ( V. parahaemolyticus , V. vulnificus and V. fluvialis ) isolated from effluent water discharged by wastewater treatment plant (WWTP) showed varied antimicrobial resistance towards ampicillin, chloramphenicol, ciprofloxacin, tetracycline, cefotaxime and trimethoprim‐sulphamethoxazole.…”

“…Vibrio species are motile Gram‐negative rods, primarily present in the aquatic habitats, including seawater, brackish water (e.g. estuaries and lagoons), sediments, sewage and freshwater environments worldwide (Osuolale & Okoh, 2018; Thompson et al, 2004). There are over 100 Vibrio species in the genus of Vibrio (Baker‐Austin et al, 2018; Romalde et al, 2014).…”

Distribution and Public Health Significance of Vibrio Pathogens Recovered from Selected Treated Effluents in the Eastern Cape Province, South Africa

“…Vibrio species are known autochthonous populations found in freshwaters and marine sediments worldwide [9,10]. Several species of Vibrio are known to cause a number of diseases in human, including cholera, gastroenteritis and primary septicaemia, and their infections arise from the ingestion of contaminated foods, water, undercooked seafoods and through wounded skin getting direct contact with contaminated water [11][12][13][14]. The upsurge of potentially pathogenic Vibrio species in freshwater resources is partially attributable to global warming induced by hydro-climatic changes [15].…”