BackgroundAvian-pathogenic Escherichia coli (APEC) are pathogenic strains of E. coli that are responsible for one of the most predominant bacterial disease affecting poultry worldwide called avian colibacillosis. This study describes the genetic determinants implicated in antimicrobial resistance among APEC isolated from different broiler farms in Egypt.Methods A total of 116 APEC were investigated by serotyping, antimicrobial resistance patterns to 10 antimicrobials, and the genetic mechanisms underlying the antimicrobial-resistant phenotypes.ResultsAntibiogram results showed that the highest resistance was observed for ampicillin, tetracycline, nalidixic acid, and chloramphenicol. The detected carriage rate of integron was 29.3% (34/116). Further characterization of gene cassettes revealed the presence gene cassettes encoding resistance to trimethoprim (dfrA1, dfrA5, dfrA7, dfrA12), streptomycin/spectinomycin (aadA1, aadA2, aadA5, aadA23), and streptothricin (sat2). To our knowledge, this the first description of the presence of aadA23 in APEC isolates. Analysis of other antimicrobial resistance types not associated with integrons revealed the predominance of resistance genes encoding resistance to tetracycline (tetA and tetB), ampicillin (bla
TEM), chloramphenicol (cat1), kanamycin (aphA1), and sulphonamide (sul1 and sul2). Among ciprofloxacin-resistant isolates, the S83L mutation was the most frequently substitution observed in the quinolone resistance-determining region of gyrA (56.3%). The bla
TEM and bla
CTX−M−1 genes were the most prevalent among APEC isolates producing extended-spectrum beta-lactamase (ESβL).ConclusionsThese findings provided important clues about the role of integron-mediated resistance genes together with other independent resistance genes and chromosomal mutations in shaping the epidemiology of antimicrobial resistance in E. coli isolates from poultry farms in Egypt.
BackgroundThe transmission of Cryptosporidium spp. and Giardia duodenalis into humans varies according to species/genotypes of the pathogens. Although infections with both parasites are recorded in Egypt, few data are available on the distribution of Cryptosporidium species and G. duodenalis genotypes. The present study assessed the occurrence and genetic diversity of Cryptosporidium spp. and G. duodenalis in Egyptian children.MethodsIn the present study, 585 fecal specimens were collected from children eight years old and younger in three provinces (El-Dakahlia, El-Gharbia and Damietta) during March 2015 to April 2016. PCR-RFLP analysis of the small subunit rRNA gene and sequence analysis of the 60 kDa glycoprotein gene were used to detect and subtype Cryptosporidium spp., respectively, whereas PCR and sequence analyses of the triose phosphate isomerase, glutamate dehydrogenase and β-giardin genes were used to detect and genotype Giardia duodenalis.ResultsThe overall infection rates of Cryptosporidium spp. and G. duodenalis were 1.4% and 11.3%, respectively. The Cryptosporidium species identified included C. hominis and C. parvum, each with three subtype families. The C. hominis subtypes were IbA6G3 (n = 2), IdA17 (n = 1), IdA24 (n = 1) and IfA14G1R5 (n = 1), while C. parvum subtypes were IIdA20G1 (n = 1), IIaA15G2R1 (n = 1), and IIcA5G3a (n = 1). The G. duodenalis identified included both assemblages A (n = 31) and B (n = 34). All G. duodenalis assemblage A belonged to the anthroponotic sub-assemblage AII, while a high genetic heterogeneity was seen within assemblage B.ConclusionsData from this study are useful in our understanding of the genetic diversity of Cryptosporidium spp. and G. duodenalis in Egypt and the potential importance of anthroponotic transmission in the epidemiology of both pathogens.Electronic supplementary materialThe online version of this article (10.1186/s13071-018-2981-7) contains supplementary material, which is available to authorized users.
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