Zika Virus Seroprevalence in Two Districts of Chincha, Ica, Peru: A Cross-Sectional Study.

In 2017, a major outbreak of Zika virus (ZIKV) infection took place in Chincha Province, Peru, where arboviral circulation had never been reported before. We conducted a cross-sectional survey (March-May 2019) in two districts of Chincha Province: Pueblo Nuevo and Chincha Baja. We included residents who were 20 to 40 years old and who had lived in these districts for at least 1 year. Serological testing combined screening with a commercial NS1 protein-based Zika IgG ELISA, and confirmation by a cytopathic effect-based virus neutralization test (VNT). Prevalence ratios (PRs) were calculated using Poisson regression with robust error variance. Four hundred participants, divided equally among districts, were enrolled. Anti-ZIKV IgG ELISA was positive for 42 participants (10.5%) and borderline for 12 (3%). Fifty-two of these 54 samples were confirmed positive by ZIKV VNT (13% of the total population). The Pueblo Nuevo district exhibited a greater ZIKV seroprevalence based on VNT results than the Chincha Baja district (23.5% versus 2.5%), with participants from the Pueblo Nuevo district being 9.4 times more likely to have a positive ZIKV VNT result. Average monthly income greater than the minimum wage and adequate water storage were found to be protective factors (PR, 0.29 and 0.24, respectively). In multivariate analysis, living in the Pueblo Nuevo district and a personal history of fever and rash were strong predictors of ZIKV positivity by VNT. The low ZIKV seroprevalence should prompt health authorities to stimulate interventions to prevent potential future outbreaks. In the Pueblo Nuevo district, the seroprevalence was greater but presumably not sufficient to ensure protective herd immunity.

High frequency of the exoU+/exoS+ genotype associated with multidrug-resistant "high-risk clones" of Pseudomonas aeruginosa clinical isolates from Peruvian hospitals.

The type III secretion system of Pseudomonas aeruginosa is an important virulence factor contributing to the cytotoxicity and the invasion process of this microorganism. The current study aimed to determine the presence of the exoU+/exoS+ genotype in P. aeruginosa clinical isolates. The presence of exoS, exoT, exoU and exoY was determined in 189 P. aeruginosa by PCR, and the presence/absence of exoU was analysed according to source infection, clonal relationships, biofilm formation, motility and antimicrobial susceptibility. The gyrA, parC, oprD, efflux pump regulators and ß-lactamases genes were also analysed by PCR/sequencing. The exoS, exoT and exoY genes were found in 100% of the isolates. Meanwhile, exoU was present in 43/189 (22.8%) of the isolates, being significantly associated with multidrug resistance, extensively drug resistance as well as with higher level quinolone resistance. However, the presence of ß-lactamases, mutations in gyrA and parC, and relevant modifications in efflux pumps and OprD were not significantly associated with exoU+ isolates. MLST analysis of a subset of 25 isolates showed 8 different STs displaying the exoU+/exoS+ genotype. The MDR basis of the exoU+ isolates remain to be elucidated. Furthermore, the clinical implications and spread of exoU+/exoS+ P. aeruginosa isolates need to be established.

Carrion's disease: more than a neglected disease.

Infections with Bartonella bacilliformis result in Carrion's disease in humans. In the first phase of infection, the pathogen causes a hemolytic fever ("Oroya fever") with case-fatality rates as high as ~90% in untreated patients, followed by a chronical phase resulting in angiogenic skin lesions ("verruga peruana"). Bartonella bacilliformis is endemic to South American Andean valleys and is transmitted via sand flies (Lutzomyia spp.). Humans are the only known reservoir for this old disease and therefore no animal infection model is available. In the present review, we provide the current knowledge on B. bacilliformis and its pathogenicity factors, vectors, possible unknown reservoirs, established and potential infection models and immunological aspects of the disease.

Specific type IV pili groups in clinical isolates of Pseudomonas aeruginosa

The relationships between specific type IV pili (TFP) groups and antibiotic resistance, biofilm formation, and bacterial motility were determined in 190 Pseudomonas aeruginosa clinical isolates. While motility and biofilm formation were determined by phenotypic assays, the presence of TFP was determined by PCR assay and antibiotic susceptibility by disk diffusion. The results showed a high ability to form biofilm (97.4%), multidrug resistance (44.7%), and the presence of a high number of motile isolates. We also found an association between strong biofilm production and multidrug resistance. Furthermore, TFP group III was associated with strong biofilm production. In contrast, the isolates with TFP group II and those without any TFP were associated with non-strong biofilm production. Regarding motility, TFP group II was associated with higher percentages of swarming, swimming, and twitching, while TFP group I showed lower percentages of swarming and twitching, and TFP group III showed lower levels of swarming and swimming. In conclusion, these findings highlight the differences in P. aeruginosa phenotypes related to the presence of specific TFP groups and their potential implications in clinical settings

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Specific type IV pili groups in clinical isolates of Pseudomonas aeruginosa.

The relationships between specific type IV pili (TFP) groups and antibiotic resistance, biofilm formation, and bacterial motility were determined in 190 Pseudomonas aeruginosa clinical isolates. While motility and biofilm formation were determined by phenotypic assays, the presence of TFP was determined by PCR assay and antibiotic susceptibility by disk diffusion. The results showed a high ability to form biofilm (97.4%), multidrug resistance (44.7%), and the presence of a high number of motile isolates. We also found an association between strong biofilm production and multidrug resistance. Furthermore, TFP group III was associated with strong biofilm production. In contrast, the isolates with TFP group II and those without any TFP were associated with non-strong biofilm production. Regarding motility, TFP group II was associated with higher percentages of swarming, swimming, and twitching, while TFP group I showed lower percentages of swarming and twitching, and TFP group III showed lower levels of swarming and swimming. In conclusion, these findings highlight the differences in P. aeruginosa phenotypes related to the presence of specific TFP groups and their potential implications in clinical settings.

Interplay between MexAB-OprM and MexEF-OprN in clinical isolates of Pseudomonas aeruginosa.

MexAB-OprM and MexEF-OprN are Pseudomonas aeruginosa efflux pumps involved in the development of antibiotic resistance. Several studies developed with laboratory strains or using a few clinical isolates have reported that the regulation system of MexEF-OprN is involved in the final levels of MexAB-OprM expression. Therefore, this study was aimed to determine the interplay between MexAB-OprM and MexEF-OprN in 90 out of 190 P. aeruginosa clinical isolates with an efflux pump overexpression phenotype. Regarding oprD, 33% (30/90) of isolates displayed relevant modifications (RM) defined as frameshift or premature stop, both related to carbapenem resistance. On the other hand, 33% of the isolates displayed RM in nalC, nalD or mexR, which were significantly associated with multidrug resistance (MDR), non-susceptibility to carbapenems, OprD alterations and strong biofilm production. Meanwhile, the RM in MexS were associated with presence of pigment (p = 0.004). Otherwise, when all the regulators were analysed together, the association between RM in MexAB-OprM regulators and MDR was only significant (p = 0.039) when mexS was the wild type. These data show the modulatory effect of MexEF-OprN on MexAB-OprM in a clinical population of P. aeruginosa. Further studies may contribute to design of novel molecules acting on this interplay to fight against antimicrobial resistance.

Rapid detection of salmonellosis due to Salmonella enterica serovar Typhimurium in Peruvian commercially bred cavies, using indigenous wild bacteriophages.

INTRODUCTION: The salmonelloses are among the commonest, most widespread human zoonotic infections. They have generated international networks to attempt their control, since they cause a spectrum of ailments, ranging from inapparent carrier states to full-blown, severe, sometimes deadly diarrheal and systemic disease. Rapid diagnosis is needed for a number of reasons. The aim of this study was to standardize and validate a phage amplification test for the identification of salmonellosis to be applied to infections of Cavia porcellus. METHODS: Native bacteriophages were isolated from infected cavies and environmental residues from commercial cavy-breeding facilities. Salmonella enterica serovar Typhimurium ATCC 14028 was used to detect, isolate and propagate the bacteriophages, and to standardize a phage amplification assay to detect S. Typhimurium from rectal swabs of cavies. The phage amplification assay was tested using 2 antiviral agents, MgSO4·7H2O (MAS) and pomegranate rind extract (PRE) plus ferrous sulfate (PRE-FeSO4). RESULTS: The final assay format chosen used PRE-FeSO4 and allowed detection of S. Typhimurium in 90 min from culture, 5 h from clinical samples, with a limit of detection at 103 pfu; sensitivity was 98.2%, specificity 98%, negative predictive value (NPV) 96.1%, and positive predictive value (PPV) 99.1%. CONCLUSION: Bacteriophage amplification is therefore an appropriate, fast procedure for detection of this pathogen in clinical samples.

Gene Therapy for Lung Cancer.

Gene therapy was originally conceived to treat monogenic diseases. The replacement of a defective gene with a functional gene can theoretically cure the disease. In cancer, multiple genetic defects are present and the molecular profile changes during the course of the disease, making the replacement of all defective genes impossible. To overcome these difficulties, various gene therapy strategies have been adopted, including immune stimulation, transfer of suicide genes, inhibition of driver oncogenes, replacement of tumor-suppressor genes that could mediate apoptosis or anti-angiogenesis, and transfer of genes that enhance conventional treatments such as radiotherapy and chemotherapy. Some of these strategies have been tested successfully in non-small-cell lung cancer patients and the results of laboratory studies and clinical trials are reviewed herein.

A window of opportunity study of potential tumor and soluble biomarkers of response to preoperative erlotinib in early stage non-small cell lung cancer.

BACKGROUND: Erlotinib is highly active in EGFR mutant NSCLC, but may benefit some with wild-type tumors. We examined pre-operative erlotinib in early stage NSCLC to assess response and correlation with potential biomarkers. RESULTS: Twenty-five patients were enrolled; 22 received erlotinib treatment and were evaluable (median follow-up 4.4 years). Histology was predominantly adenocarcinoma although 31% had squamous carcinoma. PET response was observed in 2 patients (9%), both with squamous carcinoma. Most (20/22) had stable disease (RECIST), with frequent minor radiographic regression and histologic findings of fibrosis/necrosis including in squamous histology. Only two had EGFR mutations identified, one with minor radiographic response and the other stable disease after 4 weeks of EGFR TKI. High pre-treatment serum levels of TGF-α correlated with primary resistance to erlotinib (p = 0.02), whereas high post-treatment soluble EGFR levels correlated with response (p = 0.03). EGFR, PTEN, cMET and AXL expression did not correlate with tumor response. METHODS: Clinical stage IA-IIB NSCLC patients received erlotinib 150 mg daily for 4 weeks followed by resection. Tumor response was assessed using CT, PET and pathological response. Tumor genotype was established using Sequenom Mass ARRAY; EGFR, PTEN, cMET and AXL expression was assessed by immunohistochemistry, circulating markers of EGFR activation (TGF-α, amphiregulin, epiregulin, EGFR ECD) by ELISA and EGFR, MET copy number by FISH. CONCLUSIONS: Erlotinib appears to demonstrate activity in EGFR wild-type tumors including squamous carcinoma. Further research is needed to characterize those wild-type patients that may benefit from EGFR TKI and predictive biomarkers including TGF-α, EGFR copy and others.

The right drugs at the right time for the right patient: the MD Anderson precision oncology decision support platform.

The development of resources for clinical interpretation of cancer-associated genetic alterations has significantly lagged behind the technical developments enabling their detection in a time- and cost-efficient manner. The lack of scientific and informatics decision support for oncologists can lead to no action being taken or suboptimal therapeutic choices being made, which could affect the clinical outcome of a patient as well as convoluting research findings from clinical trials. In this article, we describe the precision oncology decision support (PODS) platform developed within The Sheikh Khalifa Bin Zayed Al Nahyan Institute for Personalized Cancer Therapy (IPCT) at MD Anderson Cancer Center; the platform aims to bridge the gap between molecular alteration detection and identification of appropriate treatments.

Exogenous Restoration of TUSC2 Expression Induces Responsiveness to Erlotinib in Wildtype Epidermal Growth Factor Receptor (EGFR) Lung Cancer Cells through Context Specific Pathways Resulting in Enhanced Therapeutic Efficacy.

Expression of the tumor suppressor gene TUSC2 is reduced or absent in most lung cancers and is associated with worse overall survival. In this study, we restored TUSC2 gene expression in several wild type EGFR non-small cell lung cancer (NSCLC) cell lines resistant to the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib and analyzed their sensitivity to erlotinib in vitro and in vivo. A significant inhibition of cell growth and colony formation was observed with TUSC2 transient and stable expression. TUSC2-erlotinib cooperativity in vitro could be reproduced in vivo in subcutaneous tumor growth and lung metastasis formation lung cancer xenograft mouse models. Combination treatment with intravenous TUSC2 nanovesicles and erlotinib synergistically inhibited tumor growth and metastasis, and increased apoptotic activity. High-throughput qRT-PCR array analysis enabling multi-parallel expression profile analysis of eighty six receptor and non-receptor tyrosine kinase genes revealed a significant decrease of FGFR2 expression level, suggesting a potential role of FGFR2 in TUSC2-enhanced sensitivity to erlotinib. Western blots showed inhibition of FGFR2 by TUSC2 transient transfection, and marked increase of PARP, an apoptotic marker, cleavage level after TUSC2-erlotinb combined treatment. Suppression of FGFR2 by AZD4547 or gene knockdown enhanced sensitivity to erlotinib in some but not all tested cell lines. TUSC2 inhibits mTOR activation and the latter cell lines were responsive to the mTOR inhibitor rapamycin combined with erlotinib. These results suggest that TUSC2 restoration in wild type EGFR NSCLC may overcome erlotinib resistance, and identify FGFR2 and mTOR as critical regulators of this activity in varying cellular contexts. The therapeutic activity of TUSC2 could extend the use of erlotinib to lung cancer patients with wildtype EGFR.

Using Ontology Fingerprints to disambiguate gene name entities in the biomedical literature.

Ambiguous gene names in the biomedical literature are a barrier to accurate information extraction. To overcome this hurdle, we generated Ontology Fingerprints for selected genes that are relevant for personalized cancer therapy. These Ontology Fingerprints were used to evaluate the association between genes and biomedical literature to disambiguate gene names. We obtained 93.6% precision for the test gene set and 80.4% for the area under a receiver-operating characteristics curve for gene and article association. The core algorithm was implemented using a graphics processing unit-based MapReduce framework to handle big data and to improve performance. We conclude that Ontology Fingerprints can help disambiguate gene names mentioned in text and analyse the association between genes and articles. Database URL: http://www.ontologyfingerprint.org

Lung adenocarcinoma with concurrent KRAS mutation and ALK rearrangement responding to crizotinib: case report.

Chromosomal translocation resulting in the fusion between the echinoderm microtubule-associated protein-like 4 (EML4) gene and the anaplastic lymphoma kinase (ALK) gene was recently identified as a novel genetic alteration in a subset of non-small cell lung cancer (NSCLC). EML4-ALK translocations are rare events associated with specific clinicopathological features, such as never or light smoking history, young age and adenocarcinoma with signet ring or acinar histology. Reports suggest ALK gene arrangements are mutually exclusive with EGFR and KRAS mutations. To the best of to our knowledge, this is the first case report of a patient with concurrent KRAS mutation and ALK translocation. This patient had an excellent response to crizotinib, suggesting that the ALK translocation was the oncogenic driver.

The isolation of Balamuthia mandrillaris from environmental sources from Peru.

Balamuthia mandrillaris is an opportunistic free-living amoeba that has been reported to cause skin lesions and the fatal Balamuthia amoebic encephalitis (BAE) in humans and other animals. Currently, around 200 human BAE cases have been reported worldwide, although this number is considered to be underestimated. The highest number of BAE cases has been reported in the American continent, mainly in the southwest of the USA. Peru seems to be another hotspot for BAE with around 55 human cases having been identified, usually involving cutaneous infection, especially lesions in the central face area. The isolation of Balamuthia from environmental sources has been reported on only three prior occasions, twice from Californian soils and once from dust in Iran and so it seems that this amoeba is relatively rarely encountered in samples from the environment. We investigated that possibility of finding the amoebae in soil samples from different regions where clinical cases have been reported in Peru. Twenty-one samples were cultured in non-nutrient agar plates and were checked for the presence of B. mandrillaris-like trophozoites and/or cysts. Those samples that were positive for these amoebae by microscopic criteria were then confirmed by PCR amplification and DNA sequencing of the mitochondrial 16S rDNA gene of B. mandrillaris. We have detected the presence of B. mandrillaris in four samples collected in the regions of Piura (3) and Lima (1) where infection cases have been previously reported. We hypothesize that B. mandrillaris is present in Peru in soil and dust which therefore constitutes a source of the infection for the BAE cases previously reported in this country. Further studies should be carried out in the area to confirm the generality of this finding.

[Phagotherapy faced with Staphylococcus aureus methicilin resistant infections in mice]. / Fagoterapia frente a infecciones por Staphylococcus aureus meticilino resistente en ratones.

OBJECTIVES: To assess the bacteriophage activity in localized and systemic infections caused by Staphylococcus aureus resistant to methicilin (MRSA). MATERIALS AND METHODS: An experimental study was performed in 45 mice of the Balb/c strain divided in nine groups of five individuals. Ten naive bacteriophages were isolated through clinical samples and hospital effluents. Lytic capacity and spectrum activity was evaluated on the basis of which six phages were selected for phagotherapy trials. Additionally, a commercial bacteriophage was used. The phagotherapy was evaluated through prophylaxis, and therapy of localized and systemic infections caused by MRSA by subcutaneous and intravenous inoculation, respectively. The effectiveness of three therapeutic schemes was tested: monotherapy, phage cocktail in multiple doses and phage cocktail in a single dose. The therapeutic activity of the phages was also compared with vancomycin and clindamycin. RESULTS: The phage cocktail and the diverse dose therapy were effective in preventing and controlling MRSA localized infections; its activity was similar to the vancomycin and clindamycin activity. The single dose phage cocktail failed to control localized infection and phagotherapy was not effective in systemic infections. CONCLUSIONS: Phagotherapy could be a viable alternative for infections caused by MRSA. Further studies that assess related aspects to phages and patient safety are required.

Fagoterapia frente a infecciones por Staphylococcus aureus meticilino resistente en ratones / Phagotherapy faced with Staphylococcus aureus methicilin resistant infections in mice

Objetivos: Evaluar la actividad de los bacteriófagos frente a infecciones localizadas y sistémicas producidas por Staphylococcus aureus resistente a meticilina (MRSA) Materiales y métodos. Se realizó un estudio de tipo experimental en 45 ratones de la cepa Balb/c divididos en nueve grupos de cinco individuos. Se aislaron diez bacteriófagos nativos a partir de muestras clínicas y efluentes hospitalarios, se evaluó su capacidad lítica y su espectro de actividad, en base a lo cual se seleccionaron seis fagos para los ensayos de fagoterapia. Adicionalmente, se empleó un bacteriófago de origen comercial. La fagoterapia fue evaluada mediante profilaxis y terapia de infecciones localizadas y sistémicas causadas por la inoculación de MRSA por vía subcutánea y endovenosa respectivamente. Se probó la efectividad de tres esquemas terapéuticos: monoterapia, cóctel de fagos en múltiples dosis y de cóctel de fagos en una sola dosis. También se comparó la actividad terapéutica de los fagos frente a vancomicina y clindamicina. Resultados. El cóctel de fagos y la terapia a diversas dosis fueron efectivos para prevenir y controlar infecciones localizadas por MRSA, su actividad fue similar a la de vancomicina y clindamicina. La dosis única del cóctel de fagos no logró controlar la infección localizada; asimismo, la fagoterapia no resultó efectiva en infecciones sistémicas. Conclusiones. La fagoterapia se proyecta como una alternativa viable frente a infecciones causadas por MRSA. Se requieren estudios que evalúen aspectos relacionados con la inocuidad de los fagos frente al paciente.

Objectives: To assess the bacteriophage activity in localized and systemic infections caused by Staphylococcus aureus resistant to methicilin (MRSA). Materials and methods. An experimental study was performed in 45 mice of the Balb/c strain divided in nine groups of five individuals. Ten naive bacteriophages were isolated through clinical samples and hospital effluents. Lytic capacity and spectrum activity was evaluated on the basis of which six phages were selected for phagotherapy trials. Additionally, a commercial bacteriophage was used. The phagotherapy was evaluated through prophylaxis, and therapy of localized and systemic infections caused by MRSA by subcutaneous and intravenous inoculation, respectively. The effectiveness of three therapeutic schemes was tested: monotherapy, phage cocktail in multiple doses and phage cocktail in a single dose. The therapeutic activity of the phages was also compared with vancomycin and clindamycin. Results. The phage cocktail and the diverse dose therapy were effective in preventing and controlling MRSA localized infections; its activity was similar to the vancomycin and clindamycin activity. The single dose phage cocktail failed to control localized infection and phagotherapy was not effective in systemic infections. Conclusions. Phagotherapy could be a viable alternative for infections caused by MRSA. Further studies that assess related aspects to phages and patient safety are required.

Genotyping of potentially pathogenic Acanthamoeba strains isolated from nasal swabs of healthy individuals in Peru.

Free Living Amoebae (FLA) of Acanthamoeba genus are widely distributed in the environment and can be found in the air, soil and water; and have also been isolated from air-conditioning units. In humans, they are causative agents of a sight-threating infection of the cornea, Acanthamoeba keratitis (AK) and a fatal infection of the central nervous system known as Granulomatous Amoebic Encephalitis (GAE). In this study, a survey was conducted in order to determine the presence and pathogenic potential of free-living amoebae of Acanthamoeba genus in nasal swabs from individuals in two regions of Peru. Identification of isolates was based on cyst morphology and PCR-sequencing of the Diagnostic Fragment 3 to identify strains at the genotype level. The pathogenic potential of the isolates was also assayed using temperature and osmotolerance assays and extracellular proteases zymograms. The obtained results revealed that all isolated strains exhibited pathogenic potential. After sequencing the highly variable DF3 (Diagnostic Fragment 3) region in the 18S rRNA gene as previously described, genotype T4 was found to be the most common one in the samples included in this study but also genotype T15 was identified. To the best of our knowledge, this is the first study on the characterization of Acanthamoeba strains at the genotype level and the first report of genotype T4 and T15 in Peru.

Resistencia antibiótica de streptococcus pneumoniae en portadores nasofaríngeos sanos de siete regiones del Perú / Antibiotic resistance of streptococcus pneumoniae among healthy nasopharyngeal carriers in seven regions of Peru

Objetivos. Determinar el patrón de susceptibilidad antibiótica de cepas de Streptococcus pneumoniae aisladas de portadores nasofaríngeos sanos menores de 2 años de siete regiones del Perú. Materiales y métodos. Entre el 2007 y 2009 se tomaron muestras de hisopado nasofaríngeo a 2123 niños sanos entre 2 y 24 meses de edad en los consultorios de crecimiento y desarrollo (CRED) y vacunación de hospitales y centros de salud de Lima, Piura, Cusco, Abancay, Arequipa, Huancayo, e Iquitos. Se determinó la resistencia a diez antibióticos mediante la prueba de disco-difusión de las cepas de neumococo aisladas. Resultados. Se aislaron 572 cepas. Se encontró altas tasas de resistencia a cotrimoxazol (58%); penicilina (52,2% no-sensibles); tetraciclina (29,1%); azitromicina (28,9%), y eritromicina (26,3%). La resistencia a cloranfenicol fue baja (8,8%). Se encontró 29,5% de multirresistencia. La resistencia a la azitromicina y a la penicilina fue diferente en las siete regiones (p<0,05), hallándose el mayor porcentaje de cepas no-sensibles a penicilina en Arequipa (63,6%), mientras que el menor fue en Cusco (23,4%). Conclusiones. Los elevados niveles de resistencia encontrados para penicilina, cotrimoxazol y macrólidos en cepas de neumococo aisladas de portadores sanos en todas las regiones estudiadas, y su asociación con uso previo de antibióticos, representan un importante problema de salud pública en nuestro país. Esto resalta la necesidad de implementar, a nivel nacional, estrategias para disminuir el uso irracional de antibióticos, sobre todo en la población pediátrica. Es necesario complementar los datos de resistencia a penicilina con la determinación de la concentración mínima inhibitoria para hacer las recomendaciones terapéuticas respectivas.

Objectives. To determine the pattern of antibiotic susceptibility of isolated Streptococcus pneumoniae strains of healthy nasopharyngeal carriers younger than 2 years in seven regions of Peru. Materials and methods. Between 2007 and 2009, nasopharyngeal swab samples were collected among 2123 healthy children aged 2-24 months in growth and development medical practices (CRED) and vaccination offices of hospitals and health centers in Lima, Piura, Cusco, Abancay, Arequipa, Huancayo, and Iquitos. The resistance to ten antibiotics through disk diffusion sensitivity testing of isolated pneumococcus strains was determined. Results. 572 strains were isolated. High rates of resistance to co-trimoxazole (58%), penicillin (52.2% non-sensitive); tetracycline (29,1%); azithromycin (28,9%), and erythromycin (26,3%). Resistance to chloramphenicol was low (8.8%). Multiresistance was found at 29.5%. Resistance to azithromycin and penicillin was different in all seven regions (p<0,05), the highest percentage of non-sensitive strains being found in Arequipa (63,6%), whereas the lowest percentage was found in Cusco (23.4%). Conclusions. High levels of resistance found to penicillin, co-trimoxasole and macrolides in isolated pneumococcus strains of healthy carriers in all studied regions, and their association to a previous use of antibiotics, represent a significant public health problem in our country. This emphasizes the need to implement nationwide strategies to reduce the irrational use of antibiotics, especially among children. It is necessary to complement data of resistance to penicillin with the determination of minimal inhibitory concentration to make proper therapeutic recommendations.

A foodborne outbreak of brucellosis at a police station cafeteria, Lima, Peru.

Brucella melitensis is highly infectious for humans and can be transmitted to humans in a number of epidemiological contexts. Within the context of an ongoing brucellosis surveillance project, an outbreak at a Peruvian police officer cafeteria was discovered, which led to active surveillance (serology, blood culture) for additional cases among 49 police officers who had also eaten there. The cohort was followed up to 18 months regardless of treatment or symptoms. Active surveillance estimated the attack rate at 26.5% (13 of 49). Blood cultures from four cases were positive; these isolates were indistinguishable using multiple locus variable number tandem repeat analysis. This investigation indicates the importance of case tracking and active surveillance for brucellosis in the context of potential common source exposure. These results provide rationale for public health investigations of brucellosis index cases including the bioterrorism-related dissemination of Brucella.