Ramswaroop Singh Rathore

Arcobacter: an emerging food-borne zoonotic pathogen, its public health concerns and advances in diagnosis and control – a comprehensive review

ABSTRACT Arcobacter has emerged as an important food-borne zoonotic pathogen, causing sometimes serious infections in humans and animals. Newer species of Arcobacter are being incessantly emerging (presently 25 species have been identified) with novel information on the evolutionary mechanisms and genetic diversity among different Arcobacter species. These have been reported from chickens, domestic animals (cattle, pigs, sheep, horses, dogs), reptiles (lizards, snakes and chelonians), meat (poultry, pork, goat, lamb, beef, rabbit), vegetables and from humans in different countries. Arcobacters are implicated as causative agents of diarrhea, mastitis and abortion in animals, while causing bacteremia, endocarditis, peritonitis, gastroenteritis and diarrhea in humans. Three species including A. butzleri, A. cryaerophilus and A. skirrowii are predominantly associated with clinical conditions. Arcobacters are primarily transmitted through contaminated food and water sources. Identification of Arcobacter by biochemical tests is difficult and isolation remains the gold standard method. Current diagnostic advances have provided various molecular methods for efficient detection and differentiation of the Arcobacters at genus and species level. To overcome the emerging antibiotic resistance problem there is an essential need to explore the potential of novel and alternative therapies. Strengthening of the diagnostic aspects is also suggested as in most cases Arcobacters goes unnoticed and hence the exact epidemiological status remains uncertain. This review updates the current knowledge and many aspects of this important food-borne pathogen, namely etiology, evolution and emergence, genetic diversity, epidemiology, the disease in animals and humans, public health concerns, and advances in its diagnosis, prevention and control.

Genotyping and genetic diversity of Arcobacter butzleri and Arcobacter cryaerophilus isolated from different sources by using ERIC-PCR from India

Background: Arcobacters are important zoonotic pathogens and are transmitted through food and water. They are implicated in causing enteritis in animals and humans. Among the Arcobacter species, a wide genetic diversity has been documented, which reflects continuous evolving nature of these pathogens. Objectives: To genotype and to know the genetic diversity of Arcobacter spp. (Arcobacter butzleri and Arcobacter cryaerophilus) isolated from different sources in India. Methods: Enterobacterial repetitive intergenic consensus–polymerase chain reaction (ERIC-PCR) was performed using genomic DNA of 49 Arcobacter isolates (27 A. butzleri and 22 A. cryaerophilus), recovered from a total of 506 samples of chicken meat, poultry skin, dairy cow milk and human stool as template and employing published primers. Results: ERIC sequence was found to be present in all the 27 A. butzleri isolates which were grouped into 18 subtypes, while it was present in 20 out of 22 A. cryaerophilus isolates which were grouped into 14 subtypes. Less variation was observed within sequences of both the Arcobacter species as revealed in dendrogram analysis. The genotyping of A. butzleri isolates showed the presence of 2–8 distinct bands (∼150 to ∼1600 bp), while A. cryaerophilus showed 1–10 distinct bands (∼120 to ∼2900 bp). Conclusion:This study is the first report regarding genetic diversity of Indian Arcobacter isolates using ERIC-PCR. Close clustering between arcobacters of human and animal origin are indicative of probable zoonotic significance. So for these purposes, further explorative studies are suggested which would also help revealing the possibility of epidemiological relationships of different Arcobacter spp. as well as their public health concerns.