Sole infection by human metapneumovirus among children with radiographically diagnosed community-acquired pneumonia in a tropical region

Background Limited information is available on the role of human metapneumovirus (HMPV) as the unique pathogen among children hospitalized for community-acquired pneumonia (CAP) in a tropical region. Objective We aimed to describe HMPV infection among children with CAP investigating bacterial and viral co-infections. Patients and methods A prospective study was carried out in Salvador, North-East Brazil. Overall, 268 children aged <5 years hospitalized for CAP were enrolled. Human metapneumovirus RNA was detected in nasopharyngeal aspirates (NPA) by reverse transcription polymerase chain reaction. Sixteen other bacterial and viral pathogens were investigated by an expanded panel of laboratory methods. Chest X-ray taken on admission was read by an independent paediatric radiologist unaware of clinical information or the established aetiology. Results Human metapneumovirus RNA was detected in NPAs of 11 (4.1%) children, of which 4 (36%) had sole HMPV infection. The disease was significantly shorter among patients with sole HMPV infection in comparison with patients with mixed infection (4 +/- 1 versus 7 +/- 2 days, P = 0.03). Three of those four patients had alveolar infiltrates. Conclusion Sole HMPV infection was detected in children with CAP in Salvador, North-East Brazil. HMPV may play a role in the childhood CAP burden.

Human respiratory syncytial virus in children hospitalized for acute lower respiratory infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diversity and Adaptation of Human Respiratory Syncytial Virus Genotypes Circulating in Two Distinct Communities: Public Hospital and Day Care Center

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bovine herpesvirus-5 infection in a rabbit experimental model: Immunohistochemical study of the cellular response in the CNS

Since little information is available regarding cellular antigen mapping and the involvement of non-neuronal cells in the pathogenesis of bovine herpesvirus type 5 (BHV-5) infection, it were determined the BHV-5 distribution, the astrocytic reactivity, the involvement of lymphocytes and the presence of matrix metalloproteinase (MMP)-9 in the brain of rabbits experimentally infected with BHV-5. Twelve New Zealand rabbits that were seronegative for BHV-5 were used for virus inoculation, and five rabbits were used as mock-infected controls. The rabbits were kept in separate areas and were inoculated intranasally with 500 μl of virus suspension (EVI 88 Brazilian isolate) into each nostril (virus titer, 107.5 TCID50). Control rabbits were inoculated with the same volume of minimum essential medium. Five days before virus inoculation, the rabbits were submitted to daily administration of dexamethasone. After virus inoculation, the rabbits were monitored clinically on a daily basis. Seven rabbits showed respiratory symptoms and four animals exhibited neurological symptoms. Tissue sections were collected for histological examination and immunohistochemistry to examine BHV-5 antigens, astrocytes, T and B lymphocytes and MMP-9. By means of immunohistochemical and PCR methods, BHV-5 was detected in the entire brain of the animals which presented with neurological symptoms, especially in the trigeminal ganglion and cerebral cortices. Furthermore, BHV-5 antigens were detected in neurons and/or other non-neural cells. In addition to the neurons, most infiltrating CD3 T lymphocytes observed in these areas were positive for MMP-9 and also for BHV-5 antigen. These infected cells might contribute to the spread of the virus to the rabbit brain along the trigeminal ganglia and olfactory nerve pathways. © 2013 Elsevier Ltd.

Caracterização estrutural e das interações entre a Proteína G do hRSV e potenciais inibidores

Pós-graduação em Microbiologia - IBILCE

Prevalência de vírus respiratórios em crianças de creche com sintomas de infecções respiratórias agudas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise epidemiológica e caracterização parcial do gene F dos Metapneumovirus Humano detectados a partir de casos de infecção respiratória aguda na Região Norte do Brasil

As doenças do trato respiratório são as principais queixas nos serviços de atendimento médico, sendo as infecções respiratórias agudas (IRA) as manifestações mais comuns, principalmente em crianças menores de cinco anos de idade. Em países em desenvolvimento, as IRA constituem um sério problema de saúde pública. Em todo mundo estima-se que ocorram cerca de 2 milhões de mortes devido as IRA a cada ano. Dentre os agentes causais de IRA, destaca-se o Metapneumovírus Humano (HMPV), especialmente por causar doença grave em crianças menores de 5 anos. Com o objetivo de gerar dados sobre a epidemiologia molecular deste vírus, foram analisadas amostras colhidas de pacientes com IRA no período de Janeiro de 2009 a Dezembro de 2011 oriundas da Região Norte (Pará, Amazonas, Acre, Amapá e Roraima). Foi utilizado a técnica de RT-PCR em Tempo Real (qRT-PCR) para a detecção do vírus através da amplificação do gene N e RT-PCR para o gene codificador da proteína F, que foi em seguida parcialmente sequenciado. Dentro do período de estudo, foram testadas 2966 amostras, das quais 129 positivas para HMPV. A faixa etária de 0-4 anos foi a que concentrou maior número de casos (n=84; 65,89%) em toda a região Norte. Na identificação viral, constatou-se a co-circulação dos subgrupos A2 e B2 durante os três anos do estudo. Os subgrupos A1 e B1 não circularam na região durante o período estudado. Este estudo representa o primeiro relato sobre dados da epidemiologia molecular do Metapneumovírus Humano na região Norte do Brasil.

Epidemiology of healthcare-associated infections among patients from a hemodialysis unit in southeastern Brazil

Patients submitted to hemodialysis are at a high risk for healthcare-associated infections (HAI). Presently there are scarce data to allow benchmarking of HAI rates in developing countries. Also, most studies focus only on bloodstream infections (BSI) or local access infections (LAI). Our study aimed to provide a wide overview of HAT epidemiology in a hemodialysis unit in southeastern Brazil. We present data from prospective surveillance carried out from March 2010 through May 2012. Rates were compared (mid-p exact test) and temporally analyzed in Shewhart control charts for Poisson distributions. The overall incidence of BSI was 1.12 per 1000 access-days. The rate was higher for patients performing dialysis through central venous catheters (CVC), either temporary (RR = 13.35, 95% CI = 6.68-26.95) or permanent (RR = 2.10,95% CI = 1.09-4.13), as compared to those with arteriovenous fistula. Control charts identified a BSI outbreak caused by Pseudomonas aeruginosa in April 2010. LAI incidence was 3.80 per 1000 access-days. Incidence rates for other HAI (per 1000 patients-day) were as follows: upper respiratory infections, 1.72; pneumonia, 1.35; urinary tract infections, 1.25; skin/soft tissues infections, 0.93. The data point out to the usefulness of applying methods commonly used in hospital-based surveillance for hemodialysis units. (C) 2013 Elsevier Editora Ltda. All rights reserved.

Estudo das interações entre proteína NS1 do hRSV e flavonóides utilizando métodos biofísicos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ineraction Model Between HRSV G-Protein and Flavonoids

Background: Acute respiratory infections (ARI) are the leading cause of infant mortality in the world, and human respiratory syncytial virus (HRSV) is one of the main agents of ARI. One of the key targets of the adaptive host immune response is the RSV G-protein, which is responsible for attachment to the host cell. There is evidence that compounds such as flavonoids can inhibit viral infection in vitro. With this in mind, the main purpose of this study was to determine, using computational tools, the potential sites for interactions between G-protein and flavonoids. Results: Our study allowed the recognition of an hRSV G-protein model, as well as a model of the interaction with flavonoids. These models were composed, mainly, of -helix and random coil proteins. The docking process showed that molecular interactions are likely to occur. The flavonoid kaempferol-3-O-α-L-arabinopyranosil-(2 → 1)-α-L-apiofuranoside-7-O-α-L-rhamnopyranoside was selected as a candidate inhibitor. The main forces of the interaction were hydrophobic, hydrogen and electrostatic. Conclusions: The model of G-protein is consistent with literature expectations, since it was mostly composed of random coils (highly glycosylated sites) and -helices (lipid regions), which are common in transmembrane proteins. The docking analysis showed that flavonoids interact with G-protein in an important ectodomain region, addressing experimental studies to these sites. The determination of the G-protein structure is of great importance to elucidate the mechanism of viral infectivity, and the results obtained in this study will allow us to propose mechanisms of cellular recognition and to coordinate further experimental studies in order to discover effective inhibitors of attachment proteins.

Analysis of Climatic Factors Impact on RSV Infection Distribution in Children Attending Childcare at Northwest Region of São Paulo, Brazil

Respiratory syncytial virus (RSV) was detected in samples collected from children from 0 to 6 years of age with acute respiratory infection, attending public childcare on Northwest region of São Paulo, Brazil. RSV distribution was associated to seasonal climatic variables as temperature, rainfall and relative air humidity. We utilized samples of nasopharyngeal aspirate collected during the period of July 2003 to September 2005. RT-PCR was the chosen method for viral identification. Results showed that from the 817 samples (collected from 179 children), 7.7% (63/817) were RSV positive. In 2003, RSV was detected from July until October. In 2004, RSV infections occurred in March, May, June, July, October, November, and December. In 2005, RSV was detected in March, April, May, August, and September. RSV circulation patterns in childcare children showed seasonal distribution associated to decreases in temperature and relative air humidity. RSV was detected in childcare children as an important viral agent causing respiratory infections, with varying patterns of circulation into the cohort during the study period. Moreover, RSV distribution showed to be associated with the dry season on Northwest region of São Paulo, Brazil.

Caracterização biofísica da interação entre a proteína M2-1 do Vírus Sincicial Respiratório Humano (HRSV) com quercetina

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diversity and Adaptation of Human Respiratory Syncytial Virus Genotypes Circulating in Two Distinct Communities: Public Hospital and Day Care Center

HRSV is one of the most important pathogens causing acute respiratory tract diseases as bronchiolitis and pneumonia among infants. HRSV was isolated from two distinct communities, a public day care center and a public hospital in Sao Jose do Rio Preto - SP, Brazil. We obtained partial sequences from G gene that were used on phylogenetic and selection pressure analysis. HRSV accounted for 29% of respiratory infections in hospitalized children and 7.7% in day care center children. On phylogenetic analysis of 60 HRSV strains, 48 (80%) clustered within or adjacent to the GA1 genotype; GA5, NA1, NA2, BA-IV and SAB1 were also observed. SJRP GA1 strains presented variations among deduced amino acids composition and lost the potential O-glycosilation site at amino acid position 295, nevertheless this resulted in an insertion of two potential O-glycosilation sites at positions 296 and 297. Furthermore, a potential O-glycosilation site insertion, at position 293, was only observed for hospital strains. Using SLAC and MEME methods, only amino acid 274 was identified to be under positive selection. This is the first report on HRSV circulation and genotypes classification derived from a day care center community in Brazil.

A Randomized Trial of Noninvasive Positive End Expiratory Pressure in Patients With Acquired Immune Deficiency Syndrome and Hypoxemic Respiratory Failure

BACKGROUND: Acquired immunodeficiency syndrome (AIDS) is a pandemic disease commonly associated with respiratory infections, hypoxemia, and death. Noninvasive PEEP has been shown to improve hypoxemia. In this study, we evaluated the physiologic effects of different levels of noninvasive PEEP in hypoxemic AIDS patients. METHODS: Thirty AIDS patients with acute hypoxemic respiratory failure received a randomized sequence of noninvasive PEEP (5, 10, or 15 cm H2O) for 20 min. PEEP was provided through a facial mask with pressure-support ventilation (PSV) of 5 cm H2O and an F-IO2, of 1. Patients were allowed to breathe spontaneously for a 20-min washout period in between each PEEP trial. Arterial blood gases and clinical variables were recorded after each PEEP treatment. RESULTS: The results indicate that oxygenation improves linearly with increasing levels of PEEP. However, oxygenation levels were similar regardless of the first PEEP level administered (5, 10, or 15 cm H2O), and only the subgroup that received an initial treatment of the lowest level of PEEP (ie, 5 cm H2O) showed further improvements in oxygenation when higher PEEP levels were subsequently applied. The P-aCO2, also increased in response to PEEP elevation, especially with the highest level of PEEP (ie, 15 cm H2O). PSV of 5 cm H2O use was associated with significant and consistent improvements in the subjective sensations of dyspnea and respiratory rate reported by patients treated with any level of PEEP (from 0 to 15 cm H2O). CONCLUSIONS: AIDS patients with hypoxemic respiratory failure improve oxygenation in response to a progressive sequential elevation of PEEP (up to 15 cm H2O). However, corresponding elevations in P-aCO2, limit the recommended level of PEEP to 10 cm H2O. At a level of 5 cm H2O, PSV promotes an improvement in the subjective sensation of dyspnea regardless of the PEEP level employed.

Nursing Workload as a Risk Factor for Healthcare Associated Infections in ICU: A Prospective Study

Introduction: Nurse understaffing is frequently hypothesized as a potential risk factor for healthcare-associated infections (HAI). This study aimed to evaluate the role of nursing workload in the occurrence of HAI, using Nursing Activities Score (NAS). Methods: This prospective cohort study enrolled all patients admitted to 3 Medical ICUs and one step-down unit during 3 months (2009). Patients were followed-up until HAI, discharge or death. Information was obtained from direct daily observation of medical and nursing rounds, chart review and monitoring of laboratory system. Nursing workload was determined using NAS. Non-compliance to the nurses' patient care plans (NPC) was identified. Demographic data, clinical severity, invasive procedures, hospital interventions, and the occurrence of other adverse events were also recorded. Patients who developed HAI were compared with those who did not. Results: 195 patients were included and 43 (22%) developed HAI: 16 pneumonia, 12 urinary-tract, 8 bloodstream, 2 surgical site, 2 other respiratory infections and 3 other. Average NAS and average proportion of non compliance with NPC were significantly higher in HAI patients. They were also more likely to suffer other adverse events. Only excessive nursing workload (OR: 11.41; p: 0.019) and severity of patient's clinical condition (OR: 1.13; p: 0.015) remained as risk factors to HAI. Conclusions: Excessive nursing workload was the main risk factor for HAI, when evaluated together with other invasive devices except mechanical ventilation. To our knowledge, this study is the first to evaluate prospectively the nursing workload as a potential risk factor for HAI, using NAS.