Pathogenic potential and genotypic diversity of Campylobacter jejuni: a neglected food-borne pathogen in Brazil.
Purpose and methodology.Campylobacter jejuni is a major zoonotic pathogen that causes food-borne gastroenteritis worldwide. However, there are only a few studies available that have molecularly characterized C. jejuni strains isolated in Brazil. The aim of this study was to genotype 111 C. jejuni strains isolated from sick humans (43), monkey faeces (19), chicken faeces (14), chicken meat (33) and sewage (2) between 1996 and 2016 in Brazil using flaA-SVR (short variable region) sequencing and PFGE. Furthermore, the presence of 16 virulence genes was analysed by PCR.


RESULTS
Using PFGE and flaA-SVR sequencing, the 111 C. jejuni strains studied were grouped into three and two clusters, respectively, and some strains of different origin presented a similarity of ≥80 %. In total, 35 flaA-SVR alleles were detected. Alleles gt45, gt49 and gt57 were the most prevalent, in contrast with those frequently described in the PubMLST database. All 111 C. jejuni strains contained the genes flaA, flhA, cadF, docA, cdtA, cdtB, cdtC, iamA, ciaB, sodB, dnaJ, pldA, racR and csrA. The wlaN gene was detected in 11 strains (9.9 %), and the virB11 in just one strain (0.9 %).


CONCLUSIONS
In conclusion, the pathogenic potential of the C. jejuni strains studied was highlighted by the high frequency of the majority of the virulence genes searched. The flaA-SVR sequencing and PFGE results showed that some of the strains studied presented a high genotypic similarity, suggesting potential for transmission between animal sources and humans in this country. Altogether, the results characterize further C. jejuni isolates from Brazil, an important producer and exporter of chicken meat.
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
Miliane Rodrigues
MR
Frazão
Instituto Adolfo Lutz de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
Marta Inês Cazentini
MIC
Medeiros
Fundação Oswaldo Cruz (Fiocruz), Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
Sheila da Silva
SDS
Duque
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
Juliana Pfrimer
JP
Falcão
D000818:Animals; D001938:Brazil / Q000453:epidemiology; D002169:Campylobacter Infections / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D016123:Campylobacter jejuni / Q000235:genetics* / Q000472:pathogenicity*; D002645:Chickens / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D005408:Flagellin / Q000235:genetics; D005517:Foodborne Diseases / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D005759:Gastroenteritis / Q000453:epidemiology / Q000382:microbiology; D005798:Genes, Bacterial; D014644:Genetic Variation; D005838:Genotype; D000882:Haplorhini / Q000382:microbiology; D006801:Humans; D058069:Neglected Diseases / Q000453:epidemiology / Q000382:microbiology; D016133:Polymerase Chain Reaction; D011200:Poultry / Q000382:microbiology; D015995:Prevalence; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics*
D012722:Sewage; D037521:Virulence Factors; D005408:Flagellin; C067138:flaA protein, bacteria