CTX-M-15-producing enteroaggregative Escherichia coli as cause of travelers' diarrhea.

Travelers' diarrhea is a major public health problem. From patients in whom diarrhea developed after travel to India, 5 enteroaggregative Escherichia coli strains carrying ß-lactamase CTX-M-15 were identified; 3 belonged to clonal complex sequence type 38. This ß-lactamase contributes to the multidrug resistance of enteroaggregative E. coli, thereby limiting therapeutic alternatives.

Mometasone and desloratadine additive effect on eosinophil survival and cytokine secretion from epithelial cells.

BACKGROUND: Although antihistamines and topical corticosteroids are used in combination to treat allergic rhinitis, their additive effect has not been yet demonstrated. The aim was investigate the antiinflammatory additive effect of mometasone and desloratadine on cytokine and sICAM-1 secretion by epithelial cells, and on eosinophil survival stimulated by human epithelial cells secretions from nasal mucosa and polyps. METHODS: Epithelial cells obtained from nasal mucosa or polyps were stimulated with 10% fetal bovine serum in presence of mometasone (10(-11) M-10(-5) M) with/without desloratadine (10(-5) M). Cytokine and sICAM-1 concentrations in supernatants were measured by ELISA. Peripheral blood eosinophils were incubated during 4 days with epithelial cell secretions with (10(-11) M-10(-5) M) and/or desloratadine (10(-5) M) and survival assessed by Trypan blue. Results are expressed as percentage (mean ± SEM) compared to control. RESULTS: Fetal bovine serum stimulated IL-6, IL-8, GM-CSF and sICAM-1 secretion. In mucosa and polyp epithelial cells, mometasone inhibited this induced secretion while desloratadine inhibited IL-6 and IL-8. The combination of 10(-5) M desloratadine and 10(-9) M mometasone reduced IL-6 secretion (48 ± 11%, p < 0.05) greater extent than mometasone alone (68 ± 10%) compared to control (100%). Epithelial cell secretions induced eosinophil survival from day 1 to 4, this effect being inhibited by mometasone. At day 4, the combination of mometasone (10(-11) M) and desloratadine (10(-5) M) provoked an increased inhibition of eosinophil survival induced by cell secretions (27 ± 5%, p < 0.01) than mometasone (44 ± 7%) or desloratadine (46 ± 7%) alone. CONCLUSIONS: These results suggest that the combination of desloratadine and mometasone furoate have a greater antinflammatory effect in an in vitro model of eosinophil inflammation than those drugs administered alone.

Pilot study assessing HIV vaccine trial readiness among female sex workers, injection and non-injection drug users, and men who have sex with men in Spain.

The purpose of this study was to assess HIV risk and willingness to participate in HIV vaccine trials in three high risk populations in Spain. Eight hundred and forty-four participants, comprising female sex workers, injection and non-injection drug users (IDUs and NIDUs, respectively), and men who have sex with men were tested for HIV and surveyed for risk and willingness to participate in future preventive HIV vaccine trials. HIV seroprevalence was 3.8% (95% CI: 2-11). HIV infection was associated with transgender identification, IDU in the past year, and sex with an IDU or other drug-using partner. The majority (82%) expressed their willingness to participate in HIV vaccine trials. Substantial sexual and parenteral risk in all groups and concomitant willingness to participate in vaccine trials was found, particularly among women and IDUs. Additional longitudinal cohort studies in Spain are needed to plan future vaccine efficacy trials.

Evolution of antimicrobial resistance in enteroaggregative Escherichia coli and enterotoxigenic Escherichia coli causing traveller's diarrhoea.

OBJECTIVES: Enteroaggregative Escherichia coli (EAEC) and enterotoxigenic E. coli (ETEC) are among the most frequent microorganisms causing traveller's diarrhoea. The aim of this study was to investigate the evolution of antimicrobial resistance in EAEC and ETEC causing diarrhoea in patients who had travelled to different developing countries, comparing two periods of time, 1994-97 and 2001-04. METHODS: Overall, 134 EAEC and 190 ETEC clinical isolates were studied. The MICs of ampicillin, chloramphenicol, nalidixic acid, tetracycline, trimethoprim/sulfamethoxazole, ciprofloxacin and amoxicillin/clavulanic acid were determined by the Etest method. Detection of mutations in the quinolone-resistance determining region of the gyrA and parC genes was performed by PCR and DNA sequencing. RESULTS: When antimicrobial resistance in EAEC and ETEC isolates was compared between the two periods of time, a statistically significant increase in resistance (P < 0.01) was observed in EAEC for chloramphenicol and amoxicillin/clavulanic acid, whereas in ETEC it was for trimethoprim/sulfamethoxazole, nalidixic acid, ciprofloxacin and amoxicillin/clavulanic acid. Mutations in the gyrA gene were found in all nalidixic acid-resistant isolates, whereas mutation(s) in both gyrA and parC genes were found in the ciprofloxacin-resistant isolates. CONCLUSIONS: The high percentage of resistance to quinolones in ETEC and EAEC isolated from travellers to North Africa and India is a matter for concern. These agents should therefore be used with caution in patients with traveller's diarrhoea returning from these geographical areas.

Enhanced retention strategies and willingness to participate among hard-to-reach female sex workers in Barcelona for HIV prevention and vaccine trials.

The potential for implementation of HIV vaccine trials in hard-to-reach female sex workers in an inner city area of Barcelona, Spain was assessed via a study of HIV risk, willingness to participate and the success of retention strategies. In 130 women, serological HIV status, behavioral risk exposures and willingness to participate in future HIV vaccine trials were recorded every six months using a confidential questionnaire. An enhanced retention (ER) strategy was compared with a control retention (CR) strategy comprising the recording of data on appointment cards. HIV seroincidence and retention rates were estimated. Retention rates after 6 and 12 mo of follow-up in the ER group were 76% and 69% respectively compared with 16% and 13% in the CR group. Among the ER group 97% were willing to participate in HIV vaccine trials at baseline and, after 12 mo of follow-up. Willingness was significantly associated with higher HIV risk exposure, and higher education level. Successfully retaining these cohorts over time in settings with a high HIV seroincidence rate is an ongoing challenge that will need to be addressed to ensure participation in future trials. Furthermore, as we have demonstrated, the fact that retaining hard-to-reach populations is difficult should not exclude this target population for HIV vaccine and prevention trials.

HIV vaccine trial willingness among injection and non-injection drug users in two urban centres, Barcelona and San Francisco.

Being able to recruit high-risk volunteers who are also willing to consider future participation in vaccine trials are critical features of vaccine preparedness studies. We described data from two cohorts of injection- and non-injection drug users in Barcelona, Spain [Red Cross centre] and in San Francisco, USA, [UFO-VAX study] at high risk of HIV/HCV infection to assess behaviour risk exposure and willingness to participate in future preventive HIV vaccine trials. We successfully identified drug-using populations that would be eligible for future HIV vaccine efficacy trials, based on reported levels of risk during screening and high levels of willingness to participate. In both groups, Red Cross and UFO-VAX respectively, HCV infection was highly prevalent at baseline (41% and 34%), HIV baseline seroprevalence was 4.2% and 1.5%, and high levels of willingness were seen (83% and 78%).

Prevalence of different virulence factors and biofilm production in enteroaggregative Escherichia coli isolates causing diarrhea in children in Ifakara (Tanzania).

This study investigated the prevalence of 19 virulence factors and biofilm production in 86 EAEC isolates causing diarrhea in children less than 5 years of age from Ifakara, Tanzania. Virulence factors were detected by PCR, whereas biofilm production was determined using a microtiter plate assay. No virulence factor, with the exception of the aat gene used to identify EAEC, was detected in 11/86 isolates (12.8%). The most frequently detected virulence factor was the aggR gene in 53 (61.6%) EAEC, followed by antigen 43 in 33.7%, dispersin in 26.7%, yersiniabactin in 22.1%; autrotransporter Sat in 20.9%; Shigella enterotoxin-1 in 16.3%, and heat-stable toxin-1 in 15.1%. Biofilm was produced in 66/86 (76%) isolates. AggR was the most prevalent virulence factor in the biofilm-forming group (65% versus 38%, P = 0.032). These results again show the high heterogeneity of virulence factors among EAEC isolates causing diarrhea in children, and that biofilm may be an important virulence factor, strongly associated with the presence of AggR.