Marianne Strohmeyer

Multidrug-resistant commensal Escherichia coli in children, Peru and Bolivia.

Healthy children in urban areas have a high prevalence of fecal carriage of drug-resistant E. coli.

High Prevalence of Acquired Antimicrobial Resistance Unrelated to Heavy Antimicrobial Consumption

In a very remote rural Bolivian community where the use of antimicrobials has been minimal and where exchanges with the exterior are very limited, 67% of subjects were found to be carriers of fecal Escherichia coli with acquired resistance to >/=1 antimicrobial agent(s); the highest rates were observed for tetracycline (64%), ampicillin (58%), trimethoprim-sulfamethoxazole (50%), and chloramphenicol (41%). The most relevant implication of these findings is that, in certain settings, the spread and maintenance of antimicrobial resistance can occur, regardless of whether selective pressure generated by the use of antimicrobials is present.

Antibiotic resistance in a very remote Amazonas community

In a very remote human community of the Peruvian Amazonas with minimal antibiotic exposure, high levels of acquired resistance to the oldest antibiotics (ampicillin, tetracycline, trimethoprim/sulfamethoxazole, streptomycin and chloramphenicol) were detected in commensal Escherichia coli, with remarkable diversity of resistant clones and of resistance genes and plasmids. This pattern was similar overall to that previously observed in a very remote community of Bolivia. It was also similar to that observed in the nearest urban area, except for a lower dominance of resistant isolates and the absolute lack of quinolone resistance in the remote community. Present findings suggest that antibiotic resistance observed in remote communities with minimal antibiotic exposure is a general phenomenon contributed by complex mechanisms and provide new insights into the mechanisms involved in this phenomenon.

Epilepsy and neurocysticercosis in Latin America: a systematic review and meta-analysis.

Background The difference in epilepsy burden existing among populations in tropical regions has been attributed to many factors, including the distribution of infectious diseases with neurologic sequels. To define the burden of epilepsy in Latin American Countries (LAC) and to investigate the strength of association with neurocysticercosis (NCC), considered one of the leading causes of epilepsy, we performed a systematic review and meta-analysis of the literature. Methodology Studies published until 2012 were selected applying predefined inclusion criteria. Lifetime epilepsy (LTE) prevalence, active epilepsy (AE) prevalence, incidence, mortality, treatment gap (TG) and NCC proportion among people with epilepsy (PWE) were extracted. Median values were obtained for each estimate using random effects meta-analysis. The impact of NCC prevalence on epilepsy estimates was determined using meta-regression models. To assess the association between NCC and epilepsy, a further meta-analysis was performed on case-control studies. Principal findings The median LTE prevalence was 15.8/1,000 (95% CI 13.5–18.3), the median AE prevalence was 10.7/1,000 (95% CI 8.4–13.2), the median incidence was 138.2/100,000 (95% CI 83.6–206.4), the overall standardized mortality ratio was 1.4 (95% CI 0.01–6.1) and the overall estimated TG was 60.6% (95% CI 45.3–74.9). The median NCC proportion among PWE was 32.3% (95% CI 26.0–39.0). Higher TG and NCC estimates were associated with higher epilepsy prevalence. The association between NCC and epilepsy was significant (p<0.001) with a common odds ratio of 2.8 (95% CI 1.9–4.0). Significance A high burden of epilepsy and of NCC in LAC and a consistent association between these two diseases were pointed out. Furthermore, NCC prevalence and TG were identified as important factors influencing epilepsy prevalence to be considered in prevention and intervention strategies.

Epidemiology and Management of Cysticercosis and Taenia solium Taeniasis in Europe, Systematic Review 1990–2011

Background Cysticercosis is caused by the invasion of human or pig tissues by the metacestode larval stage of Taenia solium. In Europe, the disease was endemic in the past but the autochthonous natural life cycle of the parasite is currently completed very rarely. Recently, imported cases have increased in parallel to the increased number of migrations and international travels. The lack of specific surveillance systems for cysticercosis leads to underestimation of the epidemiological and clinical impacts. Objectives To review the available data on epidemiology and management of cysticercosis in Europe. Methods A review of literature on human cysticercosis and T. solium taeniasis in Europe published between 1990–2011 was conducted. Results Out of 846 cysticercosis cases described in the literature, 522 cases were autochthonous and 324 cases were imported. The majority (70.1%) of the autochthonous cases were diagnosed in Portugal from 1983 and 1994. Imported cases of which 242 (74.7%) diagnosed in migrants and 57 (17.6%) in European travellers, showed an increasing trend. Most of imported cases were acquired in Latin America (69.8% of migrants and 44.0% of travellers). The majority of imported cases were diagnosed in Spain (47.5%), France (16.7%) and Italy (8.3%). One third of neurosurgical procedures were performed because the suspected diagnosis was cerebral neoplasm. Sixty eight autochthonous and 5 imported T. solium taeniasis cases were reported. Conclusions Cysticercosis remains a challenge for European care providers, since they are often poorly aware of this infection and have little familiarity in managing this disease. Cysticercosis should be included among mandatory reportable diseases, in order to improve the accuracy of epidemiological information. European health care providers might benefit from a transfer of knowledge from colleagues working in endemic areas and the development of shared diagnostic and therapeutic processes would have impact on the quality of the European health systems. Key words: cysticercosis, neurocysticercosis, Taenia solium, taeniasis, Europe, travellers, migrants.

Increasing Resistance in Commensal Escherichia coli, Bolivia and Peru

To the Editor: The global increase of antimicrobial-drug resistance, including resistance to the new and most potent antimicrobial agents, is a major public health concern. In low-resource countries, where bacterial infections are still among the major causes of death, especially for children, it is of particular concern (1). ANTRES (Towards Controlling Antimicrobial Use and Resistance in Low-income Countries—An Intervention Study in Latin America) is a research project on antimicrobial-drug use and resistance in low-resource countries of Latin America (see www.unifi.it/infdis/antres/default.htm). In 2002, the baseline ANTRES study showed a high rate of fecal carriage of Escherichia coli with acquired resistance to several antimicrobial drugs, especially older drugs (e.g., ampicillin, trimethoprim-sulfamethoxazole, tetracycline, streptomycin, and chloramphenicol), in preschool children from 4 urban settings in Bolivia and Peru (2). We report the results of a second cross-sectional study, conducted in 2005, that evaluated the evolution of antimicrobial-drug resistance in the studied areas. We studied healthy children 6–72 months of age from each of 4 urban areas: 2 in Bolivia (Camiri, Santa Cruz Department; Villa Montes, Tarija Department) and 2 in Peru (Yurimaguas, Loreto Department; Moyobamba, San Martin Department). The study design, sampling and inclusion criteria, methods, and ethical issues were the same as those of the baseline study (2). The study was carried out over 4 months (September–December 2005), the same seasonal period as in the previous study. No significant differences in sex ratios were found among children enrolled from the different areas, whereas minor differences were found for age. No statistical differences were found between the 2002 baseline study and the 2005 study results in terms of numbers of children (3,193 vs. 3,174) and sex ratios (0.94 vs. 0.95) (Table). Statistical analyses were performed by using Stata 9.0 (Stata Corp., College Station, TX, USA). Logistic regression models were used to compare the antimicrobial-drug resistance rates in 2002 and 2005, considering the combined influences of age, sex, city, and country. Table Antimicrobial drug–resistance rates of Escherichia coli as part of commensal flora in children, Bolivia and Peru, 2002 and 2005* *Expanded Table available online at www.cdc.gov/EID/content/14/2/338-T.htm. Data from the 2005 survey confirmed high resistance rates for ampicillin, trimethoprim-sulfamethoxazole, tetracycline, streptomycin, and chloramphenicol. The differences in resistance rates observed between 2002 and 2005 for these drugs, although sometimes statistically significant, are probably of limited epidemiologic relevance due to the high rates of antimicrobial-drug resistance found in the E. coli population in both surveys. The most relevant finding of the 2005 survey was the remarkable increase since 2002 in the resistance rates to fluoroquinolones and expanded-spectrum cephalosporins (Table). Molecular analysis showed that the dramatic increase in rates of resistance to expanded spectrum cephalosporins was mostly the result of dissemination of CTX-M-type extended-spectrum β-lactamase determinants (3). Concerning the association between sex and resistance rates, the higher resistance rates observed for some agents and in some settings for boys in the baseline study were not confirmed, except in 1 case (kanamycin in Camiri, p = 0.04) (2). Analysis by age (not performed for amikacin due to low numbers of resistant isolates) confirmed the occurrence of higher resistance rates for the youngest age group and an overall decreasing trend by age for all agents, except ciprofloxacin and gentamicin. For these 2 agents, resistance rates increased, although not significantly (p = 0.95 and p = 0.55, respectively) (2). Although we did not specifically address factors potentially involved in this phenomenon, we will address them in future investigations. Increasing resistance to fluoroquinolones and expanded-spectrum cephalosporins among E. coli clinical isolates has been observed in several parts of the world and complicates the management of infections (4,5). Recently, intestinal colonization with fluoroquinolone-resistant or extended-spectrum β-lactamase–producing E. coli of nonhospitalized persons has been described as an emerging phenomenon (6–9). Although the exact clinical implications of this phenomenon are not clearly established, colonization by these resistant strains is a public health threat at the community and hospital levels (8,9). The reasons for the increased prevalence of fecal carriage of these resistant E. coli strains by children from the studied areas are not clear. Data collected about household use of antimicrobial drugs excluded previous use of fluoroquinolones and expanded-spectrum cephalosporins (C. Kristiansson et al., unpub. data). The increased prevalence of resistant E. coli strains in preschool children most likely reflects increased exposure within a contaminated household setting, in the food chain, or both (6,8,10). Our findings support the need to continue monitoring the evolution of resistance in commensal E. coli, to evaluate the effects of these important reservoirs of resistance genes distributed in the community, to investigate the epidemiologic relationship with clinical isolates, and to define the role of the food supply. Investigation into whether carriage of resistant strains in adults correlates with data on antimicrobial-drug use in hospitals and in the community would also be of interest.

A scoping review of cost-effectiveness of screening and treatment for latent tuberculosis infection in migrants from high-incidence countries

BackgroundIn low-incidence countries, most tuberculosis (TB) cases occur among migrants and are caused by reactivation of latent tuberculosis infection (LTBI) acquired in the country of origin. Diagnosis and treatment of LTBI are rarely implemented to reduce the burden of TB in immigrants, partly because the cost-effectiveness profile of this intervention is uncertain.The objective of this research is to perform a review of the literature to assess the cost-effectiveness of LTBI diagnosis and treatment strategies in migrants.MethodsScoping review of economic evaluations on LTBI screening strategies for migrants was carried out in Medline.ResultsNine studies met the inclusion criteria. LTBI screening was cost-effective according to seven studies. Findings of four studies support interferon gamma release assay as the most cost-effective test for LTBI screening in migrants. Two studies found that LTBI screening is cost-effective only if carried out in immigrants who are contacts of active TB cases.Discussion and ConclusionsOur findings support the cost-effectiveness of LTBI diagnostic and treatment strategies in migrants especially if they are focused on young subjects from high incidence countries. These strategies could represent and adjunctive and synergistic tool to achieve the ambitious aim of TB elimination.

Access to health care in relation to socioeconomic status in the Amazonian area of Peru

BackgroundAccess to affordable health care is limited in many low and middle income countries and health systems are often inequitable, providing less health services to the poor who need it most. The aim of this study was to investigate health seeking behavior and utilization of drugs in relation to household socioeconomic status for children in two small Amazonian urban communities of Peru; Yurimaguas, Department of Loreto and Moyobamba, Department of San Martin, Peru.MethodsCross-sectional study design included household interviews. Caregivers of 780 children aged 6–72 months in Yurimaguas and 793 children of the same age in Moyobamba were included in the study. Caregivers were interviewed on health care seeking strategies (public/private sectors; formal/informal providers), and medication for their children in relation to reported symptoms and socio-economic status. Self-reported symptoms were classified into illnesses based on the IMCI algorithm (Integrated Management of Childhood Ilness). Wealth was used as a proxy indicator for the economic status. Wealth values were generated by Principal Component Analysis using household assets and characteristics.ResultsSignificantly more caregivers from the least poor stratum consulted health professionals for cough/cold (p < 0.05: OR = 4.30) than the poorest stratum. The poorest stratum used fewer antibiotics for cough/cold and for cough/cold + diarrhoea (16%, 38%, respectively) than the least poor stratum (31%, 52%, respectively). For pneumonia and/or dysentery, the poorest used significantly fewer antibiotics (16%) than the least poor (80%).ConclusionThe poorest seek less care from health professionals for non-severe illnesses as well as for severe illnesses; and treatment with antibiotics is lacking for illnesses where it would be indicated. Caregivers frequently paid for health services as well as antibiotics, even though all children in the study qualified for free health care and medicines. The implementation of the Seguro Integral de Salud health insurance must be improved.

Methicillin-resistant Staphylococcus aureus in hospitalized patients from the Bolivian Chaco

OBJECTIVES Information is lacking on the methicillin-resistant Staphylococcus aureus (MRSA) clonal lineages circulating in Bolivia. We investigated the prevalence and molecular epidemiology of S. aureus colonization in hospitalized patients from the Bolivian Chaco, and compared their features with those of the few clinical isolates available from that setting. METHODS S. aureus nasal/inguinal colonization was investigated in 280 inpatients from eight hospitals in two point prevalence surveys (2012, n=90; 2013, n=190). Molecular characterization included genotyping (spa typing, multilocus sequence typing, and pulsed-field gel electrophoresis), detection of virulence genes, and SCCmec typing. RESULTS Forty-one inpatients (14.6%) were S. aureus nasal/inguinal carriers, of whom five were colonized by MRSA (1.8%). MRSA isolates mostly belonged to spa-type t701, harboured SCCmec IVc, and were negative for Panton-Valentine leukocidin (PVL) genes. However, a USA300-related isolate was also detected, which showed the characteristics of the USA300 Latin American variant (USA300-LV; i.e., ST8, spa-type t008, SCCmec IVc, presence of PVL genes, absence of arcA). Notably, all the available MRSA clinical isolates (n=5, collected during 2011-2013) were also identified as USA300-LV. CONCLUSIONS Overall, MRSA colonization in inpatients from the Bolivian Chaco was low. However, USA300-LV-related isolates were detected in colonization and infections, emphasizing the importance of implementing control measures to limit their further dissemination in this resource-limited area.

Molecular Alterations of VanA Element in Vancomycin-Resistant Enterococci Isolated During a Survey of Colonized Patients in an Italian Intensive Care Unit

To screen for vancomycin-resistant enterococci (VRE) colonization in hospitalized patients and to study molecular evolution and alterations of Tn1546-like elements in VRE among potentially at-risk patients, a 3-year surveillance protocol in an Intensive Care Unit was performed. A total of 397 patients were screened in the period June, 1997-June, 2000, and VRE were isolated from rectal swabs taken at admission, weekly, and when clinically indicated. The susceptibility of the enterococci was determined by the disk diffusion and broth dilution methods. The presence of vancomycin-resistance genes (vanA, vanB, and vanC) was assessed by polymerase chain reaction (PCR); genetic clonality of isolates was assessed by pulsed-field gel electrophoresis (PFGE); Tn1546 types were obtained by restriction fragment length polymorphism (RFLP) analysis of Tn1546 PCR fragments. Thirty-four strains, 31 identified as Enterococcus faecium and 3 strains as E. faecalis, were isolated from 12 of the 397 patients (3.0%); all strains were VanA as assessed by PCR and were resistant to the other antibiotics tested and showed high-level resistance to aminoglycosides. Enterococci isolated during the study period showed that different genetic backgrounds of strains, determined by PFGE combined with RFLP of Tn1546, are present in all the strains isolated in the study. PFGE type B was predominant in 1998 and 1999, and insertion sequence movements were found to have a role in the evolution of VanA resistance elements found in all strains. This study demonstrates that single patients may be colonized by closely related VRE with several PFGE types containing a wide variety of VanA elements. Moreover, isolates with identical PFGE types may contain different VanA elements reflecting rearrangements mediated by insertion sequences in VRE strains during their stay in the gastrointestinal tract.