Nosocomial virus infections cause significant morbidity and mortality. Besides influenza viruses, the disease burden of parainfluenza virus type 3 (PIV-3) is comparatively high among hospitalized patients and severe disease courses can occur. PIV-3 showed the highest rates of nosocomial infections of a panel of respiratory viruses. Therefore, a retrospective observational study was conducted among patients with either PIV-3 or influenza viruses, which served as reference pathogen. The aim was to compare the seasonal dynamics and clinical characteristics of nosocomial infections with these highly transmittable viruses. Nosocomial infection occurred in 15.8% (n = 177) of all influenza cases, mainly in the first half of a season. About 24.3% (n = 104) of the PIV-3 cases were nosocomial and occurred mainly in the second half of a season. Both nosocomial rates of influenza and nosocomial rates of PIV-3 varied between the seasons. Community acquired and nosocomial cases differed in underlying medical conditions and immunosuppression. Knowledge of the baseline rates of nosocomial infections could contribute to the implementation of appropriate infection control measures.

The first chapter of this thesis is centered around a simple problem: to do or not to do something. As in life, every decision has an unknown outcome and planning agents try to balance the trade offs of such decision based on some relevant information. After processing the relevant information a decision is reached. In this chapter, the problem is formalized and parameterized in two frameworks: In the first framework discrete decision models known as decision trees are studied, where we design an optimization algorithm to solve the misclassification cost problem in this family of representations; The second framework studies continuously differentiable models (such as logistic regression and Deep Neural Networks) where we propose a two-step optimization procedure of the misclassification cost problem, as well as characterizing the statistical estimation problem relative to the sample size used for training. We illustrate the methodology by developing a computerized scheme to administer (or not) a preventive intervention to patients arriving to the hospital with the objective of minimizing their risk of acquiring a Hospital Acquired Infection (HAI). The second chapter expands on the idea of the first one to a sequential setting. The problem is framed as a Markov Decision Process algorithm using a state aggregation strategy based on Decision Trees. These incremental state aggregations are solved using a Linear Programming (LP) approach to obtain a compact policy that converges to the optimal one asymptotically, as well as showing that the computational complexity of our algorithm depends on the tree structure of the optimal policy rather than the cardinality of the state space. We illustrate the advantages of our approach using the widely known cartpole balancing environment against a Deep Neural Network based approach showing that with a similar computational complexity our algorithm performs better in certain instances of MDP. In the last two chapters we deal with modeling Emergency Medical Service (EMS) optimization such that the demand for medical services is met with the best possible supply allocation in the face of uncertainty of the demand in space and time. In the third chapter we develop a short-term prediction model for call volume at a 911 call center. The rationale of the model is to use the recent call volume to update a historically calibrated model of the call volume that in periods when the call volume distribution drastically changes, can be arbitrarily distant from its expected value. The model is casted as a linear correction of the historical estimation, calculating both the mean and variance of the correction. We justify the formulation using a regime switching doubly stochastic process framework to illustrate the type of distribution changes our model captures. We also propose a staffing model to preemptively staff a call center using our volume prediction as input for the call center demand such that the waiting times of the customers are minimized. This formulation can be casted as a Second Order Cone Program (SOCP) or a Linear Program (LP) with integrality constraints. We illustrate the methodology to predict the call volume during the Covid-19 pandemic to a 911 call center in New York City. In the fourth chapter we modify a well known set covering formulation to perform ambulance scheduling such that the supply of ambulances matches the demand in space and time. We enhance this model using a high resolution simulation model to correct an unknown steady-state service rate of the system (dependent on many exogenous and endogenous factors such as the ambulance dispatch policy and time-varying traffic patterns) as a constraint in the scheduling formulation. We show that this formulation effectively makes the system faster by maximizing the minimum slack between supply and demand during a 24-hour period. We present an algorithm to iteratively solve the scheduling formulation while correcting the implied location and time dependent service rate of the ambulance system using the simulation generated ambulance waiting times of patients in the city. We illustrate our algorithm to schedule municipally managed ambulances in New York City as a case study.

An increase in outbreaks caused by zoonotic agents has brought about intensified efforts to address the transmission of infectious organisms in animal settings. In October 2002, the CDC released recommendations for the use of waterless hand sanitizer (WHS) in human healthcare settings. The question arises whether WHS may be as effective in veterinary and animal agricultural settings given some of the dissimilarities in conditions. To address this question, three studies were conducted. The first was a retrospective analysis of a Samonella agona outbreak which occurred in 2001 at the Large Animal Teaching Hospital of the Virginia-Maryland Regional College of Veterinary Medicine (VMRCVM). The second evaluated the pattern of use and efficacy of hand hygiene products in the VMRCVM Large Animal Hospital. The third study assessed the efficacy of WHS among visitors to a children's petting zoo at the 2002 Virginia State Fair. Regarding the Salmonella outbreak, it is thought that a calf from the university owned dairy herd was the index case. A total of 16 equine patients acquired S. agona while hospitalized. The nosocomial disease incidence risk for in-house patients was estimated to be 33% (16/49). The LAH was closed for 7 months for cleaning, disinfection and renovation. The total cost of the outbreak was estimated to be at least $755,000. Waterless hand sanitizer proved useful in the veterinary hospital setting. When measured immediately after use, WHS reduced bacterial loads on the hands of 20 LAH personnel (P < 0.001). Before WHS use, HBC ranged from less than to 20 to 48,800 CFU/ml with a geometric mean of 6,926 CFU/ml. Counts after WHS use ranged from less than 20 to 23,400 with a geometric mean of 1,152 CFU/ml. Differences in before and after ranged from -4,000 to 48,200 CFU/ml with a median of 9,700 CFU/ml. The logarithmic reduction in bacterial load before and after WHS use was 0.78 (79.7%). In the petting zoo study, bacterial counts on the fingers of the children sampled before use of WHS ranged from 40 to 75,200 CFU/ml with a geometric mean of 8,653 CFU/ml. After WHS use, bacterial growth ranged from 19 to 58,400 CFU/ml with a geometric mean of 1,727 CFU/ml. Differences in before and after ranged from -35,600 to 59,400 CFU/ml with a median of 8,190 CFU/ml. The logarithmic reduction in bacterial load before and after WHS use was 0.70 (82.2%; P< 0.001). These data suggest that WHS may be of benefit in veterinary medicine and animal agriculture as a means to reduce nosocomial and zoonotic infections. / Master of Science

Yes / Recent studies portend a rising global spread and adaptation of human- or healthcare- associated pathogens. Here, we analyse an international collection of the emerging, multi-drug-resistant, opportunistic pathogen Stenotrophomonas maltophilia from 22 countries to infer population structure and clonality at a global level. We show that the S. maltophilia complex is divided into 23 monophyletic lineages, most of which harbour strains of all degrees of human virulence. Lineage Sm6 comprises the highest rate of human-associated strains, linked to key virulence and resistance genes. Transmission analysis identifies potential outbreak events of genetically closely related strains isolated within days or weeks in the same hospitals.

Made available in DSpace on 2016-01-26T12:51:45Z (GMT). No. of bitstreams: 1 marcelospegiorinmoreno_tese.pdf: 1082572 bytes, checksum: d3881298debccf50a2a1f76433f765a4 (MD5) Previous issue date: 2011-02-24 / Resumo:Introdução: Pneumonias adquiridas no hospital (PAH) e pneumonias associadas à ventilação mecânica (PAVM) são complicações frequentes e importantes causas de aumento da morbidade, mortalidade e dos custos. Objetivo: O objetivo do estudo foi avaliar o valor prognóstico da dosagem seriada da PCR nos pacientes com pneumonia nosocomial (PN). Casuística e Método: Estudo prospectivo e observacional, conduzido em uma UTI de 24 leitos em um hospital terciário. Pacientes com PN, incluindo pacientes não ventilados e pacientes com pneumonia associada à ventilação mecânica foram incluídos. Dosagens diárias da PCR e cálculo da Taxa da PCR (TPCR) eram realizadas do dia da prescrição do antibiótico (D0) até o décimo dia. Pacientes foram classificados de acordo com a TPCR em 2 grupos: boa resposta (TPCR < 0,67 no D10) e má resposta (não-resposta ou resposta bifásica - TPCR 0,67 no D10). Resultados: Cento e cinquenta e cinco pacientes com PN foram avaliados e 64 foram incluídos. O grupo má resposta (n= 34) teve uma taxa de mortalidade geral de 53% em comparação a 20% no grupo boa resposta (n= 30) (RR = 2,65; IC 95%, 1,21-5,79, p = 0,01). Diferenças significantes entre os xii dois grupos foram encontradas a partir do Dia 4 (p= 0,01). A adequacidade da antibioticoterapia foi muito menor no grupo má resposta em comparação ao grupo boa resposta, 14,3% vs 66,7% (p = 0,008), respectivamente. Conclusão: Dosagens seriadas de PCR e a análise da cinética da TPCR são úteis no seguimento de pacientes com pneumonia nosocomial.

Les infections nosocomiales sont causées par des germes opportunistes souvent résistants aux antibiotiques et persistants sur les surfaces, représentant une source constante de risque d’infection en milieu hospitalier. Dans ce contexte, l’isolement et la caractérisation de bactériophages s’attaquant spécifiquement aux bactéries nosocomiales telles que Staphylococcus aureus résistant (SARM), Enterococcus résistant (ERV), Pseudomonas aeruginosa et Acinetobacter baumanii, pourraient fournir une alternative bactéricide naturelle contre la transmission de ces infections. Des phages isolés des eaux usées, ont été sélectionnés selon leur capacité d’amplification, leur profil génomique et leur potentiel lytique envers différentes souches bactériennes cliniques. Les meilleurs ont été caractérisés en détail pour s’assurer de leur spécificité, sécurité, stabilité et efficacité préalablement à leur utilisation in vivo. Sept phages contre SARM et trois contre Acinetobacter baumanii ont été caractérisés. Quatre phages SARM s’avèrent être de bons candidats potentiels et pourraient être testés en milieu hospitalier comme agents désinfectants dans le but de lutter contre les infections nosocomiales. / Nosocomial infections are directly related to opportunistic germs, which are often resistant to antibiotics and persistent on surfaces, representing a high infectious risk in hospitals. In this context, the isolation and characterization of bacteriophages specifically targeting nosocomial bacteria such as resistant Staphylococcus aureus (MRSA), resistant Enterococcus (VRE), Pseudomonas aeruginosa and Acinetobacter baumanii, could provide a natural bactericidal alternative against the transmission of these infections. Phages, isolated from waste water, were selected according to their capacity of amplification, their genomic profile and lytic potential towards various bacterial clinical strains. The best ones were characterized in detail to primarily ensure their specificity, safety, stability and effectiveness, before studying their in vivo usage. Seven phages against MRSA and three against Acinetobacter baumanii were characterized. Four MRSA phages proved to be good potential candidates and could be tested in hospitals as disinfectant agents with the aim of fighting nosocomial infections.

The graduation theses is about urinary tract infections and the preventive care that we are able to provide within nursing care of patients with urinary catheter. The theoretical part of graduation theses includes the chapters about general introduction to nosocomial infections, as well as epidemiology, pathogenesis, diagnosis and treatment of urinary tract infections. Furthermore, it relates to their antibiotic therapy and resistence to antibiotics. The main task is the prevention of urinary tract infections. Generally I have focused on the methods of urinary catheterization and their correct indications, the materials and design of urinary catheters, as well as on nursing care of urinary catheters. The thesis includes research aimed at providing preventive measures that are implemented in practice, comparing them to each other and comparison with the current studies and recommendations.. This research provides both positive and negative results. Some of the recommendations for preventive care of urinary tract infections are being followed, other are being omitted. There are also differences between respondents from different departments as well as among the departments. Nursing care procedures are not unified despite of presence of guidelines and standard procedures. keywords: nosocomial...

This thesis examines in detail the nature of postoperative infectious complications in patients who underwent brain tumor surgery. It deals with the incidence of these complications and their severity, depending on various factors and suggests the most appropriate nursing procedures used in the care of a patient in whom these complications occurred. For the structure of the work is divided into two parts - theoretical and empirical. The theoretical part deals with the issues examined in terms of the medical field Neurosurgery (closer diagnoses, conditions, operations and other procedures, and complications to occur after these operations or expected performance), analyzes a nursing practice and patient care on neurosurgical ICU, and finally closely examines infections and nosocomial diseases, including a description of the most common types, their agents, diagnosis and treatment. The second, empirical part focuses on the problems from a practical point of view. With the help of set of case studies it closer which specific complications are most commonly found on the neurosurgical ICU in patients after surgery of brain tumors, what are the most common methods of treatment and nursing procedures which are most used in the care of patients with these complications. In conclusion summarizes the...

Clostridium difficile est responsable de 15 à 25% des cas de diarrhées post-antibiotiques (ATB) et de plus de 95% des cas de colite pseudomembraneuse. Depuis 2003 et suite à l'émergence du clone 027, les ICD sont devenues plus fréquentes et plus sévères. Compte tenu des conséquences, il a été décidé d'explorer en détail et prospectivement cette maladie au Groupement Hospitalier Edouard Herriot L'inclusion des patients a débuté fin février 2011 et devrait s'arrêter fin février 2014. Dans une méta-analyse, nous avons montré que l'ICD communautaire est associée à l'exposition aux mêmes ATB qu'une ICD nosocomiale. Une analyse de la littérature, en utilisant la grille ORION comme outil, nous a permis de synthétiser les connaissances sur la prévention et le contrôle d'ICD en milieu hospitalier. Par la suite sur la base d'une étude rétrospective, le sexe, la CRP et l'exposition aux fluoroquinolones ont été identifiés comme associés à une ICD sévère chez les patients hospitalisés en réanimation. Entre 2011 et 2013, 430 patients ont été inclus dans notre cohorte. L'analyse des données de la prise en charge thérapeutique de 118 cas d'ICD a montré un niveau insuffisant de la connaissance des recommandations actuelles concernant le traitement de cette infection. L'analyse pronostique a montré un taux de mortalité de 19,5% dans les 30 jours qui suivent le diagnostic. L'ICD était indiquée comme une cause principale ou contributive de décès dans quinze cas (65,7% des décédés). Les analyses multivariées ont montré que les facteurs associés au décès sont différents entre les patients avec une ICD et les patients présentant une diarrhée non liée au Clostridium difficile / Clostridium difficile is responsible for almost all cases of pseudomembranous colitis and for 15%-25% of cases of post-antibiotic (ATB) diarrhea. Since 2003 and the emergence of 027 strain, CDI epidemiology is changing, with evidence of rising incidence and severity. In response to the alarming situation we decided to conduct a prospective study at Eduard Herriot Hospital to explore in details this infection. Patient’s inclusion has started in February 2011 and will end in February 2014. In a meta-analysis we found that the risk profiles for antimicrobial classes as risk factors for community-acquired CDI are similar to those described for nosocomial CDI. We used the ORION statement (Outbreak Reports and Intervention Studies Of Nosocomial infection) to synthesize knowledge of interventions to reduce and to control CDI in hospitals. Then in a retrospective study, we found that male gender, rising serum C-reactive protein level, and previous exposure to fluoroquinolones were independently associated with severe CDI in ICU. Between 2011 and 2013, 430 patients were included in our prospective cohort study. Data analysis of 118 cases of CDI showed an inefficient knowledge of current recommendations of CDI treatment. The crude mortality rate within 30 days after CDI diagnosis was 19.5%, with 15 deaths (65.7% of deceased patients) related to CDI. In a multivariate cox regression model, gender, serum albumin, antidiarrheal medications, cephalosporins, peritonitis and septic shock were independently associated with mortality in CDI patients. When diarrhea was not related to C. difficile, mortality was rather associated with cancer and high WBC level

O gênero Acinetobacter tem sido implicado em grande variedade de infecções hospitalares, principalmente em Unidades de Terapia Intensiva. O tratamento de infecções por Acinetobacter spp. é geralmente realizado com imipenem embora não haja ensaios clínicos randomizados que embasem esta recomendação. No caso de resistência a esta classe, situação cada vez mais freqüente, as opções mais estudadas são as polimixinas e ampicilinasulbactam. Diante da escassez de dados sobre o assunto, estudos que avaliem o tratamento de infecções por Acinetobacter spp resistente a carbapenem são necessários. Realizou-se um estudo de coorte retrospectivo de pacientes com infecção causada por Acinetobacter spp. resistente a carbapenem, internados no Instituto Central do Hospital das Clínicas (HC-FMUSP) e no Hospital do Servidor Público Estadual (HSPE) no período de 1996 a 2004. Foram considerados como casos os pacientes com diagnóstico de infecção hospitalar baseado em critérios estabelecido pelo Centers for Disease Control and Prevention (CDC) somado ao isolamento de Acinetobacter spp. resistente a carbapenem obtidos de materiais estéreis ou lavado bronco-alveolar.Não foram incluídos casos de infecção do trato urinário. Foi realizada a análise dos prontuários dos pacientes e foram coletadas informações clínico-demográficas, tratamento utilizado, sinais, sintomas e exames auxiliares no diagnóstico da infecção e no decorrer do tratamento. Foram avaliados três desfechos: mortalidade até o final do tratamento, mortalidade até o final da internação e evolução clínica. Oitenta e dois pacientes (30%) receberam polimixina B ou E, oitenta e cinco (31%) foram tratados com ampicilina-sulbactam, 99 (36%) não receberam tratamento específico. As características clínico-demográficas dos grupos foram semelhantes. A mortalidade durante a internação foi de 78% e boa resposta clínica foi observada em 50% dos pacientes tratados. Na análise multivariada de fatores associados à má evolução clínica, início do tratamento após 72 horas do isolamento e piora da função renal durante o tratamento foram estatisticamente significativos. Pontuação de Apache II >= 15, início do tratamento após 72 horas do isolamento; piora da função renal durante o tratamento; presença de choque séptico e uso de polimixina foram variáveis associadas com óbito até o final do tratamento. As variáveis independentemente associadas com óbito durante a internação foram: idade >= 58 anos, presença de choque séptico no dia do início do tratamento e pontuação de Apache II >=15. Concluiu-se que para o tratamento de infecções causadas por Acinetobacter spp. resistente a carbapenem, ampicilinasulbactam foi superior a polimixinas considerando mortalidade durante o tratamento. / Acinetobacter spp. is a cause of a number of infections, mainly in the ICU setting. Antimicrobials drugs frequently reported as active against Acinetobacter spp include carbapenems, colistin, ampicillin/sulbactam, amikacin, rifampin and tetracyclines and currently carbapenens are considered the main antimicrobial treatment. Unfortunately, over the past years there has been a worldwide increase in infections caused by carbapenem-resistant Acinetobacter. This poses a therapeutic challenge as few treatment options are avaible. We performed a retrospective review of the case records of patients from 1996 to 2004 who had nosocomial infections caused by carbapenem-resistant Acinetobacter spp. from 2 large teaching hospitals. Diagnosis of infection was based on CDC criteria plus the isolation of Acinetobacter from a usually sterile site or from broncoalvelolar lavage. Urinary tract infections were not included. We collected data on demographic and clinical features, treatment, signs and symptoms from medical records. We evaluate 3 outcomes: mortality until the end of treatment, in-hospital mortality and clinical outcome. Eighty two patients received polymyxins (30%), 85 were treated with ampicilin-sulbactam (31%) and 99 (36%) did not receive any of these antibiotics. The demographic and clinical characteristics of the groups were similar. Multivariate analysis showed that treatment with polymyxins, Apache II score >= 15; septic shock; treatment delay and renal failure were independent predictors of mortality. On multivariate analysis, age >= 58 years, presence of septic shock and Apache II score >=15 were prognosis factors for mortality during hospitalization. Multiple logistic regression analysis revealed that Apache II >=15 and renal failure during treatment were associated with treatment failure. In conclusion, ampicillin-sulbactam was superior to polymyxin considering mortality during treatment.