Distribution of ERIC-PCR genotypes among 172 <i>E</i>. <i>coli</i> isolated from human and cattle in in Tanzania.

<p>Distribution of ERIC-PCR genotypes among 172 <i>E</i>. <i>coli</i> isolated from human and cattle in in Tanzania.</p

Characterisation of Commensal <i>Escherichia coli</i> Isolated from Apparently Healthy Cattle and Their Attendants in Tanzania

<div><p>While pathogenic types of <i>Escherichia coli</i> are well characterized, relatively little is known about the commensal <i>E</i>. <i>coli</i> flora. In the current study, antimicrobial resistance in commensal <i>E</i>. <i>coli</i> and distribution of ERIC-PCR genotypes among isolates of such bacteria from cattle and cattle attendants on cattle farms in Tanzania were investigated. Seventeen <i>E</i>. <i>coli</i> genomes representing different ERIC-PCR types of commensal <i>E</i>. <i>coli</i> were sequenced in order to determine their possible importance as a reservoir for both antimicrobial resistance genes and virulence factors. Both human and cattle isolates were highly resistant to tetracycline (40.8% and 33.1%), sulphamethazole-trimethoprim (49.0% and 8.8%) and ampicillin (44.9% and 21.3%). However, higher proportion of resistant <i>E</i>. <i>coli</i> and higher frequency of resistance to more than two antimicrobials was found in isolates from cattle attendants than isolates from cattle. Sixteen out of 66 ERIC-PCR genotypes were shared between the two hosts, and among these ones, seven types contained isolates from cattle and cattle attendants from the same farm, suggesting transfer of strains between hosts. Genome-wide analysis showed that the majority of the sequenced cattle isolates were assigned to phylogroups B1, while human isolates represented phylogroups A, C, D and E. In general, <i>in silico</i> resistome and virulence factor identification did not reveal differences between hosts or phylogroups, except for <i>lpfA</i> and <i>iss</i> found to be cattle and B1 phylogroup specific. The most frequent plasmids replicon genes found in strains from both hosts were of <i>IncF</i> type, which are commonly associated with carriage of antimicrobial and virulence genes. Commensal <i>E</i>. <i>coli</i> from cattle and attendants were found to share same genotypes and to carry antimicrobial resistance and virulence genes associated with both intra and extraintestinal <i>E</i>. <i>coli</i> pathotypes.</p></div

Antimicrobial resistance of 185 <i>E</i>. <i>coli</i> isolates from cattle and cattle attendants in Tanzania.

<p>Antimicrobial resistance of 185 <i>E</i>. <i>coli</i> isolates from cattle and cattle attendants in Tanzania.</p

Minimal inhibitory concentration (MIC) of sertraline and tetracycline alone or combined.

<p>For each combination exposure on sertraline and tetracycline, the fractional inhibitory concentration index (FICI) is stated.</p

Treatment with high-dose antidepressants severely exacerbates the pathological outcome of experimental <i>Escherichia coli</i> infections in poultry

<div><p>There is an urgent need for novel antibiotics as the current antibiotics are losing their value due to increased resistance among clinically important bacteria. Sertraline, an on-marked anti-depressive drug, has been shown to modify bacterial activity <i>in vitro</i>, including increasing the susceptibility of <i>Escherichia coli</i> to antibiotics. The aim of the present study was to investigate if the antimicrobial activity of sertraline could be documented under clinical settings, hereunder if sertraline could potentiate the effect of tetracycline in treatment of an experimentally induced ascending infection in poultry. A total of 40 chickens were divided in four groups of 10 chickens each. All chickens were challenged with 4x10³ colony forming units (CFU) of a tetracycline resistant <i>E</i>. <i>coli</i> strain using a surgical infection model, and subsequently treated with either high-dose sertraline, tetracycline, a combination hereof or received no treatment. Seven days post challenge all birds were submitted to necropsy and scored pathologically for lesions. The average lesion scores were significantly higher (P<0.05) in the groups that were treated with high-dose sertraline or high-dose sertraline combined with tetracycline. In conclusion high-dose treatments (four times the maximum therapeutic dose for treating human depression) with sertraline as an adjuvant for treatment of antibiotic resistant <i>E</i>. <i>coli</i> infections exacerbate the pathological outcome of infection in chickens.</p></div

The correlation between the antibiotic resistance profile and <i>in silico</i> prediction of antimicrobial resistance genes in 17 sequenced isolates of commensal <i>E</i>. <i>coli</i> from cattle and cattle attendants in Tanzania.

<p>The correlation between the antibiotic resistance profile and <i>in silico</i> prediction of antimicrobial resistance genes in 17 sequenced isolates of commensal <i>E</i>. <i>coli</i> from cattle and cattle attendants in Tanzania.</p

Characteristics of 17 commensal <i>Escherichia coli</i> isolates from cattle and cattle attendants in Tanzania selected for whole genome sequencing.

<p>Characteristics of 17 commensal <i>Escherichia coli</i> isolates from cattle and cattle attendants in Tanzania selected for whole genome sequencing.</p

Virulence, resistance genes and plasmid replicons in 17 <i>E</i>. <i>coli</i> isolates.

<p>The presence of virulence, antibiotic resistance genes and plasmid replicons in 17 <i>Escherichia coli</i> genomes from cattle and cattle attendants in Tanzania in relation to their ERIC-PCR genotype, source of isolation and phylogenetic group. Black boxes show the presence and white boxes the absence of the relevant gene in each isolate. Isolates indicated with green were isolated from cattle, and isolates in orange—from human. Blocks indicate the host association of the strain based on ERIC-PCR.</p

Weight changes during infection.

<p>Percent weight change seven days after infection compared to before infection per chicken in the different treatment groups.</p

Overview of experimental groups.

<p>Each group consisted of 10 commercially brown layers, 45 weeks of age.</p