Relação entre temperatura do ar e incidência de dengue: estudo de séries temporais em Minas Gerais, Brasil (2010-2019) / Relationship between air temperature and dengue incidence: time series study in Minas Gerais, Brazil (2010-2019) / Relación entre la temperatura del aire y la incidencia del dengue: estudio de series temporales en Minas Gerais, Brasil (2010-2019)

Resumo A temperatura do ar é um fator climático que afeta a incidência da dengue, com efeitos variando conforme o tempo e o espaço. Investigamos a relação entre a temperatura mínima do ar e a incidência da doença em Minas Gerais, Brasil, e avaliamos a influência de variáveis socioeconômicas e geográficas nessa relação, calculando-se o risco relativo (RR). Este é um estudo de série temporal com análise conduzida em três etapas distintas: modelagem por uso de distributed lag non-linear model (modelos não-lineares distributivos com defasagem), metanálise dos modelos obtidos e metarregressão com dados geográficos e socioeconômicos. A temperatura mínima foi um fator de proteção quando em temperaturas frias extremas (RR = 0,65; IC95%: 0,56-0,76) e moderadas (RR = 0,71; IC95%: 0,64-0,79) e fator de risco em temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), mas não em extremo (RR = 1,1; IC95%: 0,99-1,22). A heterogeneidade dos modelos foi elevada (I2 = 60%) e essa medida não foi alterada em metarregressão. Temperaturas frias moderadas e extremas causam efeito protetivo, enquanto moderadas quentes aumentam o risco. No entanto, a temperatura mínima do ar não explica nem a variabilidade da região, nem mesmo com as outras variáveis em metarregressão.

Abstract Air temperature is a climatic factor that affects the incidence of dengue, with effects varying according to time and space. We investigated the relationship between minimum air temperature and dengue incidence in Minas Gerais, Brazil, and evaluated the influence of socioeconomic and geographic variables on this relationship. This is a time series study with analysis conducted in three distinct stages: modeling using a distributed lag non-linear model, meta-analysis of models obtained, and meta-regression with geographic and socioeconomic data. Minimum temperature was a protective factor at extreme cold temperatures (RR = 0.65; 95%CI: 0.56-0.76) and moderate cold temperatures (RR = 0.71; 95%CI: 0.64-0.79), and a risk factor at moderate hot temperatures (RR = 1.15; 95%CI: 1.07-1.24), but not at extreme hot temperatures (RR = 1.1; 95%CI: 0.99-1.22). Heterogeneity of the models was high (I2 = 60%), which was also observed in meta-regression. Moderate and extreme cold temperatures have a protective effect, while moderate hot temperatures increase the risk. However, minimum air temperature does not explain the variability in the region, not even with the other variables in meta-regression.

Resumen La temperatura del aire es un factor climático que afecta la incidencia del dengue, con efectos que varían según el tiempo y el territorio. Investigamos la relación entre la temperatura mínima del aire y la incidencia de la enfermedad en Minas Gerais, Brasil, y evaluamos la influencia de variables socioeconómicas y geográficas en esta relación. Se trata de un estudio de serie temporal cuyo análisis se realiza en tres etapas distintas: modelación mediante el uso de distributed lag non-linear model (modelos distributivos no lineales con retraso), metaanálisis de los modelos obtenidos y metarregresión con datos geográficos y socioeconómicos. La temperatura mínima fue un factor de protección ante temperaturas extremadamente frías (RR = 0,65; IC95%: 0,56-0,76) y moderadas (RR = 0,71; IC95%: 0,64-0,79) y factor de riesgo en temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), pero no en extremo (RR = 1,1; IC95%: 0,99-1,22). La heterogeneidad de los modelos fue alta (I2 = 60%), y esta medida no se modificó en la metarregresión. Las temperaturas frías moderadas y extremas tienen un efecto protector, mientras que las temperaturas moderadamente altas aumentan el riesgo. Sin embargo, la temperatura mínima del aire no explica la variabilidad de la región, ni siquiera con las demás variables en metarregresión.

Perfil clínico-epidemiológico de pacientes com suspeita de síndrome respiratória aguda grave durante um período de cinco anos em um município de grande porte de Minas Gerais / Clinical and epidemiological profile of severe acute respiratory syndrome suspected patients during a period of five years in a large city of Minas Gerais

Introdução: As infecções do trato respiratório representam importante causa de morbidade e mortalidade no mundo. Dentre as apresentações clínicas das infecções virais temos a síndrome respiratória aguda grave (SRAG) que é um quadro de síndrome gripal com sinais de gravidade, representando um agravo de notificação compulsória. Objetivo: Avaliar a ocorrência da síndrome respiratória aguda grave na população de Juiz de Fora, Minas Gerais, durante o período de 5 anos. Material e Métodos: Os dados clínico/epidemiológicos presentes nas fichas de notificação entre os anos de 2016 a 2021 foram fornecidos pela vigilância epidemiológica do município sendo submetidos à análise, perfazendo 20.817 pacientes estudados. Resultados: A média de idade entre 2016 e 2019 foi de 24,36 anos (DP± 25,7) e entre 2020 e 2021 a média foi de 52,17 anos (DP± 24,4). Entre 2016-2019, o acometimento por faixa etária, se concentrou entre pacientes infantis (0-2 anos) 25,41% dos casos, crianças (3-12 anos) 22,31% e adultos jovens (18-39 anos) 23,45% dos casos. Entre 2019 e 2021, houve mudança nesse perfil com maior ocorrência dos casos concentrados em adultos de meia idade e idosos. Em relação à etiologia, o vírus Influenza foi responsável por 6,11 % dos casos, 19,4% foram causados por outros vírus respiratórios e o SARS-CoV-2 em 2 anos foi responsável por 72,59% dos casos. Entre 2019 e 2021, 99,41% dos casos precisaram de internação sendo que 48,01% dos pacientes foram para a unidade de terapia intensiva (UTI). Pacientes com fatores de risco apresentaram Odds Ratio de 3,7 de evoluir para óbito. Conclusão: Em Juiz de Fora, há um predomínio de casos em pacientes de 0-12 anos seguidos por adultos jovens (18-39 anos). A Covid-19 alterou o perfil epidemiológico de acometimento. Outros vírus respiratórios, além do Influenza podem ser etiologia de casos graves. Quase 100% dos casos necessitaram de internação em enfermaria, além disso, quase 50% dos casos necessitam de cuidados em UTI.

Introduction: Respiratory tract infections represent a significant cause of morbidity and mortality worldwide. Among the clinical presentations of viral infections the Severe Acute Respiratory Syndrome (SARS) which is a severe flu-like syndrome with signs of severity, representing a notifiable condition. Objective: To evaluate the occurrence of Severe Acute Respiratory Syndrome in the population of Juiz de Fora, MG, during a 5-year period. Material and Methods: Clinical/epidemiological data from notification forms between the years 2016 and 2021 were provided by the epidemiological surveillance of the municipality and subjected to analysis, comprising 20,817 studied patients.Results: The mean age between 2016 and 2019 was 24.36 years (SD ± 25.7), and between 2020 and 2021, the average age was 52.17 years (SD ± 24.4). Between 2016-2019, the affected age groups were mainly Infants (0-2 years) accounting for 25.41% of cases, Children (3-12 years) with 22.31%, and Young Adults (18-39 years) with 23.45% of cases. Between 2019 and 2021, there was a profile change, with a higher occurrence of cases concentrated among middle-aged adults and the elderly. Regarding etiology, the Influenza virus was responsible for 6.11% of cases, 19.4% were caused by other respiratory viruses, and the SARS-CoV-2 virus accounted for 72.59% of cases in a years period. Between 2019-2021, 99.41% of cases required hospitalization, with 48.01% of patients admitted to the ICU. Patients with risk factors presented an odds ratio of 3.7 to progress to death. Conclusion: In Juiz de Fora city, there is a predominance of cases in patients aged 0-12, followed by young adults (18-39 years). COVID-19 has altered the epidemiological profile of SARS. Besides Influenza, other respiratory viruses can be the etiology of severe cases. Almost 100% of the cases required hospitalization in the ward, and nearly 50% of the cases required ICU care.

Genomic Analyses of Potential Novel Recombinant Human Adenovirus C in Brazil.

Human Adenovirus species C (HAdV-C) is the most common etiologic agent of respiratory disease. In the present study, we characterized the nearly full-length genome of one potential new HAdV-C recombinant strain constituted by Penton and Fiber proteins belonging to type 89 and a chimeric Hexon protein of types 1 and 89. By using viral metagenomics techniques, we screened out, in the states of Tocantins and Pará, Northern and North regions of Brazil, from 2010 to 2016, 251 fecal samples of children between 0.5 to 2.5 years old. These children were presenting acute diarrhea not associated with common pathogens (i.e., rotavirus, norovirus). We identified two HAdV-C strains in two distinct patients. Phylogenetic analysis performed using all complete genomes available at GenBank database indicated that one strain (HAdV-C BR-245) belonged to type 1. The phylogenetic analysis also indicated that the second strain (HAdV-C BR-211) was located at the base of the clade formed by the newly HAdV-C strains type 89. Recombination analysis revealed that strain HAdV-C BR-211 is a chimera in which the variable regions of Hexon gene combined HAdV-C1 and HAdV-C89 sequences. Therefore, HAdV-C BR-211 strain possesses a genomic backbone of type HAdV-C89 and a unique insertion of HAdV-C1 in the Hexon sequence. Recombination may play an important driving force in HAdV-C diversity and evolution. Studies employing complete genomic sequencing on circulating HAdV-C strains in Brazil are needed to understand the clinical significance of the presented data.

The occurrence of polyomaviruses WUPyV and KIPyV among patients with severe respiratory infections.

In 2007, the new polyomaviruses WUPyV and KIPyV were identified in patients with acute respiratory infections. The aim of this study was to investigate these viruses in hospitalized patients with severe acute respiratory infection (SARI). A retrospective study was conducted with 251 patients, from April 2009 to November 2010, using nasopharyngeal aspirates, naso- and oropharyngeal swab samples from hospitalized patients (children < 12 years and adults) who had SARI within 7 days of the onset of symptoms, including fever (> 38.8 °C), dyspnea, and cough. Clinical and epidemiological information was obtained through standardized questionnaire. Enrolled patients were initially suspected to have influenza A(H1N1)pdm09 infections. WUPyV and KIPyV were detected by real-time PCR. Samples were also tested for influenza A and B viruses, human respiratory syncytial virus, rhinovirus, metapneumovirus, coronavirus, adenovirus, and parainfluenza viruses. WUPyV and KIPyV were detected in 6.77% (4.78% and 1.99%, respectively) of hospitalized patients with SARI. All samples from children showed coinfections (rhinovirus was the most commonly detected). Six adults had polyomavirus infection and four (1.6%) had monoinfection. Of them, 3 reported comorbidities including immunosuppression and 1 patient had worse outcome, requiring ICU admission. These preliminary data may suggest a possible role of polyomaviruses in SARI among immunocompromised adult patients.

Detection of herpes simplex-1 and -2 and varicella zoster virus by quantitative real-time polymerase chain reaction in corneas from patients with bacterial keratitis / Detecção de vírus herpes simplex tipo 1 e 2 e varicella zoster por reação em cadeia de polimerase em tempo real em córneas de pacientes com ceratites bacterianas

ABSTRACT Objective: Bacterial keratitis occurs worldwide, and despite recent developments, it remains a potentially blinding condition. This study assesses the presence of herpes simplex virus (HSV-1 and -2) and varicella zoster virus (VZV) by quantitative real-time polymerase chain reaction (qPCR) in corneal scrapings from patients with bacterial keratitis. Methods: A total of 65 patients with clinical diagnoses of infectious corneal ulcers prospectively underwent clinical eye examinations. Corneal scrapings were investigated by Gram staining, Giemsa staining, culture, and qPCR (the study group). Risk factors and epidemiological data were recorded. The control group comprising 25 eyes with typical herpes dendritic keratitis was also analyzed by qPCR. Results: From the study group (n=65), nine patients (13.8%) had negative smears, cultures, and qPCR findings. Fifty-six (86.2%) patients had positive cultures: 51 for bacteria, 4 for fungi, and 1 for amoebae. Of the patients who had positive bacterial cultures, qPCR identified 10 patients who were also positive for virus: one for VZV and nine for HSV-1. Of the 25 patients in the control group, 21 tested positive for HSV-1 by qPCR analysis. Conclusions: Herpes may be present in patients with bacterial corneal ulcers, and qPCR may be useful in its detection.

RESUMO Objetivo: Ceratites bacterianas ocorrem mundialmente e apesar dos novos desenvolvimentos permanece como uma condição que pode levar à cegueira. Avaliar a presença de herpes simples (-1 e -2) e vírus varicella zoster (VZV) por reação em cadeia quantitativa de polimerase em tempo real (qPCR) em raspados corneanos de pacientes com ceratite bacteriana. Métodos: Sessenta e cinco pacientes com ceratite infecciosa foram submetidos a raspados corneanos estudados para gram, Giemsa, cultura e qPCR (grupo de estudo). Foram avaliados fatores de risco e epidemiológicos. O grupo controle foi composto por 25 casos de úlcera dendrítica típica por herpes analisados por qPCR. Resultados: Do grupo de estudo (n=65), nove pacientes (13,8%) apresentaram cultura, qPCR e raspado negativos. Cinquenta e seis (86,2%) pacientes apresentaram cultura positiva, 51 para bacteria, 4 para fungo e 1 para ameba. A qPCR identificou 10 pacientes do grupo de cultura positiva para bactéria que também foram positivos para vírus, um VZV e 9 para HSV-1. Dos 25 pacientes que compunham o grupo controle, 21 apresentaram qPCR positivo para HSV-1. Conclusão: Herpes pode estar presente em pacientes com úlceras de córnea bacterianas e a qPCR pode ser útil na sua detecção.

Detección de virus parainfluenza en pacientes inmunocomprometidos e inmunocompetentes atendidos en un hospital terciario de la Ciudad de São Paulo, Brasil / Detection of parainfluenza virus in immunocompromised and immunocompetent patients in a tertiary hospital in Sao Paulo, Brazil

Parainfluenza virus infections (PIV) were evaluated in patients with mild and severe infections through real time PCR. One thousand and sixty-seven samples were collected from subjects as follows: 233 adult renal transplanted outpatients, 129 children with congenital heart disease, 381 with adult hematopoietic stem cell patients and 324 hospitalized patients suspected of influenza A (H1N1) pdm09 infection. PIV was detected in 74 (6.9%) samples. VPI-3 was the most frequent (60.8%) and a higher risk was observed for older adults (p = 0.018) and for those who were hematopoietic stem cell transplanted. Further studies are needed to understand the VPI role in patients' at risk for developing serious illness.

Se evaluó la infección por virus parainfluenza (VPI) en pacientes con infecciones leves y graves mediante RPC en tiempo real. Se analizó un total de 1.067 muestras: 233 provenían de pacientes ambulatorios adultos receptores de trasplantes renales, 129 de niños con cardiopatía congénita, 381 de pacientes receptores de trasplantes de precursores hematopoyéticos adultos y 324 de pacientes hospitalizados con sospecha de influenza A (H1N1) pdm09. Se detectó VPI en 74 muestras (6,9%). Siendo VPI-3 el virus más frecuente (60,8%), se observó un mayor riesgo para los adultos mayores (p = 0,018) y para aquellos que fueron receptores de precursores hematopoyéticos. Son necesarios estudios adicionales para entender el papel del VPI en pacientes de riesgo para desarrollar enfermedad grave.

[Detection of parainfluenza virus in immunocompromised and immunocompetent patients in a tertiary hospital in Sao Paulo, Brazil]. / Detección de virus parainfluenza en pacientes inmunocomprometidos e inmunocompetentes atendidos en un hospital terciario de la Ciudad de São Paulo, Brasil.

Parainfluenza virus infections (PIV) were evaluated in patients with mild and severe infections through real time PCR. One thousand and sixty-seven samples were collected from subjects as follows: 233 adult renal transplanted outpatients, 129 children with congenital heart disease, 381 with adult hematopoietic stem cell patients and 324 hospitalized patients suspected of influenza A (H1N1) pdm09 infection. PIV was detected in 74 (6.9%) samples. VPI-3 was the most frequent (60.8%) and a higher risk was observed for older adults (p = 0.018) and for those who were hematopoietic stem cell transplanted. Further studies are needed to understand the VPI role in patients' at risk for developing serious illness.

Optimisation of a quantitative polymerase chain reaction-based strategy for the detection and quantification of human herpesvirus 6 DNA in patients undergoing allogeneic haematopoietic stem cell transplantation.

Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and early diagnosis of related clinical diseases, constitute essential measures to improve outcomes. A prospective survey on the incidence and clinical features of HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the impact of this infection on HSCT outcome remains unclear. A rapid test based on real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen and quantify clinical samples for HHV-6. The detection step was based on reaction with TaqMan® hydrolysis probes. A set of previously described primers and probes have been tested to evaluate efficiency, sensitivity and reproducibility. The target efficiency range was 91.4% with linearity ranging from 10-106 copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of plasma. The qPCR assay developed in the present study was simple, rapid and sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this test may be useful as a practical tool to help elucidate the clinical relevance of HHV-6 infection and reactivation in different scenarios and to determine the need for surveillance.

Application of molecular assay for adenovirus detection among different pediatric patients / Aplicação de teste molecular para detecção de adenovírus em pacientes pediátricos distintos

OBJECTIVE: Adenoviruses play an important role in the etiology of severe acute lower respiratory infection, especially in young children. The aim of the present study was to evaluate the Human Adenovirus (HAdV) detection by different methods (Direct Fluorescence Assay DFA and Nested Polymerase Chain Reaction nested PCR), among samples collected from different groups of pediatric patients. METHODS: Collection of samples was made in children with congenital heart disease (CHD 123 nasal aspirates collected in the years of 2005, 2007 and 2008) and in community children (CC 165 nasal aspirates collected in 2008). Children were eligible if they presented acute respiratory infection (ARI) of probable viral etiology, within up to 7 days of symptoms' onset. All studied samples were evaluated by DFA and nested PCR assay. RESULTS: Of the 290 samples included during the study period, 43 (14.8%) were positive on at least one test: 17/165 (10.3%) of the CC and 26/125 (20.8%) of the CHD children. The nested PCR detection rates in the community children were 15/165 (9.1%), and for children with CHD, 24/125 (19.2%). Molecular method showed higher detection rates when compared to the DFA test (p<0.001). Univariate analysis showed that children with congenital heart disease presented a significantly higher chance for acquiring the HAdV (Odds Ratio 2.3; 95% CI: 1.18-4.43). CONCLUSIONS: Based on data obtained in the present evaluation, we suggest that a routine surveillance should be performed in high risk patients by molecular methods, thus improving diagnostic flow and efficiency.

OBJETIVO: Os adenovírus desempenham um papel importante na etiologia da infecção aguda grave do trato respiratório inferior, especialmente entre crianças. O objetivo do estudo foi avaliar a detecção do adenovírus humano (HAdV) por diferentes métodos (imunofluorescência direta DFA e reação em cadeia da polimerase nested nested PCR) em amostras coletadas de diferentes populações de pacientes pediátricos. MÉTODOS: O material foi coletado de crianças portadoras de doença cardíaca congênita (DCC 123 aspirados nasais coletados em 2005, 2007 e 2008) e de crianças da comunidade (CC 165 aspirados nasais coletados em 2008). As crianças eram consideradas elegíveis se apresentassem infecção respiratória aguda (IRA) de provável etiologia viral, com até sete dias de início dos sintomas. Todas as amostras coletadas no estudo foram avaliadas por meio de DFA e nested PCR. RESULTADOS: De 209 amostras incluídas, 43 (14,8%) foram positivas em pelo menos um dos testes feitos: 17/165 (10,3%) das crianças da comunidade e 26/125 (20,8%) das crianças cardiopatas. As taxas de detecção por nested PCR foram 15/165 (9,1%) em crianças da comunidade e 24/125 (19,2%) em crianças cardiopatas. O método molecular mostrou maiores taxas de detecção quando comparado com a DFA (p<0,001). A análise univariada mostrou que as crianças portadoras de cardiopatia congênita apresentaram chance significativamente maior de adquirir HAdV (odds ratio 2,3; IC 95%: 1,18-4,43). CONCLUSÕES: Baseado nos resultados obtidos na presente avaliação, recomenda-se a vigilância de rotina em pacientes de risco (DCC) por métodos moleculares, que melhora o fluxo diagnóstico e a eficiência da detecção.

Optimisation of a quantitative polymerase chain reaction-based strategy for the detection and quantification of human herpesvirus 6 DNA in patients undergoing allogeneic haematopoietic stem cell transplantation

Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and early diagnosis of related clinical diseases, constitute essential measures to improve outcomes. A prospective survey on the incidence and clinical features of HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the impact of this infection on HSCT outcome remains unclear. A rapid test based on real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen and quantify clinical samples for HHV-6. The detection step was based on reaction with TaqMan® hydrolysis probes. A set of previously described primers and probes have been tested to evaluate efficiency, sensitivity and reproducibility. The target efficiency range was 91.4% with linearity ranging from 10-106 copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of plasma. The qPCR assay developed in the present study was simple, rapid and sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this test may be useful as a practical tool to help elucidate the clinical relevance of HHV-6 infection and reactivation in different scenarios and to determine the need for surveillance.

[Application of molecular assay for adenovirus detection among different pediatric patients]. / Aplicação de teste molecular para detecção de adenovírus em pacientes pediátricos distintos.

OBJECTIVE: Adenoviruses play an important role in the etiology of severe acute lower respiratory infection, especially in young children. The aim of the present study was to evaluate the Human Adenovirus (HAdV) detection by different methods (Direct Fluorescence Assay - DFA and Nested Polymerase Chain Reaction - nested PCR), among samples collected from different groups of pediatric patients. METHODS: Collection of samples was made in children with congenital heart disease (CHD - 123 nasal aspirates collected in the years of 2005, 2007 and 2008) and in community children (CC - 165 nasal aspirates collected in 2008). Children were eligible if they presented acute respiratory infection (ARI) of probable viral etiology, within up to 7 days of symptoms' onset. All studied samples were evaluated by DFA and nested PCR assay. RESULTS: Of the 290 samples included during the study period, 43 (14.8%) were positive on at least one test: 17/165 (10.3%) of the CC and 26/125 (20.8%) of the CHD children. The nested PCR detection rates in the community children were 15/165 (9.1%), and for children with CHD, 24/125 (19.2%). Molecular method showed higher detection rates when compared to the DFA test (p<0.001). Univariate analysis showed that children with congenital heart disease presented a significantly higher chance for acquiring the HAdV (Odds Ratio 2.3; 95% CI: 1.18-4.43). CONCLUSIONS: Based on data obtained in the present evaluation, we suggest that a routine surveillance should be performed in high risk patients by molecular methods, thus improving diagnostic flow and efficiency.

Avaliação situacional de influenza pós pandemia de 2009 - uma breve revisão / Situational assessment of influenza post 2009 Pandemic - a brief review

Os vírus influenza são responsáveis por epidemias anuais com gravidade da doença variável. Causam infecção respiratória aguda com elevada transmissibilidade devido sua alta variabilidade genética, capacidade de adaptação e rápida disseminação. Os vírus influenza apresentam genoma fragmentado,o que ocasiona variações antigênicas frequentes, e consequentemente pode induzir o aparecimento de subtipos mais virulentos, como ocorreu em 2009,quando foi registrada pandemia por um novo vírus Influenza A H1N1. A Organização Mundial de Saúde(OMS) estima que a gripe acometa 5 a 15% da população,ocasionando 3 a 5 milhões de casos graves e 250.000 a 500.000 mortes anualmente. As epidemias anuais de gripe e o risco de novas pandemias tornamo monitoramento epidemiológico do vírus influenza fundamental e, para isto, a OMS coordena a Rede Mundial de Vigilância da Influenza com a finalidade de fornecer informações necessárias para a escolha das variantes virais que farão parte da composição anual da vacina, visto que a vacinação é uma das medidas mais efetivas para prevenção da gripe e suas complicações. Além disso, a rede constitui uma vigilância rápida para identificações de vírus influenza emergentes com potencial epidêmico ou pandêmico.Esta vigilância é viabilizada pelos resultados dos testes laboratoriais que são ferramentas importantes para a Saúde Pública, sendo fundamentais para a contenção e prevenção dos vírus circulantes. O objetivo deste estudo foi apresentar informações relacionadas ao vírus influenza e a doença, como são realizados o diagnóstico e monitoramento pelas redes de vigilâncias mundiais pós-pandemia e, ainda, quais os novos desafios que se apresentam.

Influenza viruses are responsible for annual epidemics with patients presenting variable degrees of diseases everity. These virus can cause acute respiratory infection with a high transmissibility due to its high genetic variability, adaptability and rapid spread. Influenza viruses have fragmented genome which causes frequent antigenic variation, which can result in more virulent subtypes emergence, as occurred in 2009 when it was described a new pandemic influenza virus H1N1. WHO estimates that flu affects 5-15% of the population and it causes 3 to 5 million of severe cases and 250.000 to 500.000 deaths annually. The annual influenza epidemics and the new pandemics risk high lights the importance of Influenza virus epidemiological monitoring. Based in this concern WHO created and coordinates the Global Influenza Surveillance and Response System in order to provide necessary information for viral variants selection that will be part of vaccine annual composition, since that, vaccination is one of the most effective measures for influenza prevention and its complications. In addition, the network is a rapid surveillance of emerging influenza virus identifications with potential to cause epidemic or pandemic situations. The surveillance isenable due to laboratory tests results which are important tools for public health, with essential role for circulating viruses containment and prevention. The aim of this study was to present information related to influenza virus and flu disease, how the diagnosis and monitoring are performed by global surveillance networks at post pandemic time and, also,the new challenges facing.

Influenza virus surveillance among young children in São Paulo, Brazil: the impact of vaccination

This study assessed the presence of influenza virus among young children and the coverage of vaccination from 2010 to 2012 in São Paulo, Brazil. Our results demonstrated a lower rate of influenza detection and a predominance of influenza B. A decrease of coverage vaccination through the surveillance periods was observed.

Comparison of the direct fluorescence assay and real-time polymerase chain reaction for the detection of influenza virus A and B in immunocompromised patients.

OBJECTIVE: This study evaluated the diagnostic performance of two methods for the detection of influenza virus in immunocompromised transplant patients. METHODS: A total of 475 respiratory samples, 236 from patients in a hematopoietic stem cell transplantation program and 239 from kidney transplant patients, were analyzed by a direct fluorescence assay and the Centers for Disease Control real-time polymerase chain reaction protocol for influenza A and B detection. RESULTS: Influenza detection using either method was 7.6% in the hematopoietic stem cell transplant group and 30.5% in the kidney transplant patient group. Influenza detection by real-time polymerase chain reaction yielded a higher positive rate compared with fluorescence than that reported by other studies, and this difference was more pronounced for influenza A. The fluorescence assay sensitivity, specificity, positive and negative predictive values, and kappa coefficient were 17.6%, 100%, 1, 0.83, and 0.256, respectively, and lower detection rates occurred in the kidney transplant patients. CONCLUSIONS: The real-time polymerase chain reaction performance and the associated turnaround time for a large number of samples support the choice of this method for use in different routine diagnostic settings and influenza surveillance in high-risk patients.

Comparison of the direct fluorescence assay and real-time polymerase chain reaction for the detection of influenza virus A and B in immunocompromised patients

OBJECTIVE: This study evaluated the diagnostic performance of two methods for the detection of influenza virus in immunocompromised transplant patients. METHODS: A total of 475 respiratory samples, 236 from patients in a hematopoietic stem cell transplantation program and 239 from kidney transplant patients, were analyzed by a direct fluorescence assay and the Centers for Disease Control real-time polymerase chain reaction protocol for influenza A and B detection. RESULTS: Influenza detection using either method was 7.6% in the hematopoietic stem cell transplant group and 30.5% in the kidney transplant patient group. Influenza detection by real-time polymerase chain reaction yielded a higher positive rate compared with fluorescence than that reported by other studies, and this difference was more pronounced for influenza A. The fluorescence assay sensitivity, specificity, positive and negative predictive values, and kappa coefficient were 17.6%, 100%, 1, 0.83, and 0.256, respectively, and lower detection rates occurred in the kidney transplant patients. CONCLUSIONS: The real-time polymerase chain reaction performance and the associated turnaround time for a large number of samples support the choice of this method for use in different routine diagnostic settings and influenza surveillance in high-risk patients. .

Human adenovirus detection among immunocompetent and immunocompromised patients presenting acute respiratory infection.

INTRODUCTION: Human adenoviruses (HAdV) play an important role in the aetiology of severe acute lower respiratory infection, especially in immunocompromised individuals. The aim of the present study was to detect HAdV using two different methods, direct fluorescence assay (DFA) and nested polymerase chain reaction (nested PCR), in samples collected from patients with acute groups from 2001 to 2010: 139 adult emergency room patients (ERP); 205 health care workers (HCW); 69 renal transplant outpatients(RTO); and 230 patients in a haematopoietic stem cell transplantation program (HSCT). RESULTS: Adenovirus was detected in 13.2% of the 643 patients tested by DFA and/or PCR: 6/139 (4.3%) adults in the ERP group, 7/205 (3.4%) in the HCW group, 4/69 (5.8%) in the RTO group and 68/230 (29.5%) in the HSCT patient group. Nested PCR had a higher detection rate (10%) compared with the DFA test (3.8%) (p<0.001). HSCT patients exhibited a significantly higher rate of HAdV infection. CONCLUSIONS: The adenovirus detection rate of the nested PCR assay was higher than that of the DFA test. However, the use of molecular methods in routine diagnostic laboratory work should be evaluated based on the specific circumstances of individual health services.

Human adenovirus detection among immunocompetent and immunocompromised patients presenting acute respiratory infection

INTRODUCTION: Human adenoviruses (HAdV) play an important role in the etiology of severe acute lower respiratory infection, especially in immunocompromised individuals. The aim of the present study was detect the HAdV through different methods: direct fluorescence assay (DFA) and nested-polymerase chain reaction (PCR-nested) from patients with acute respiratory infection (ARI) up to 7 days of symptoms onset. METHODS: Samples (n=643) were collected from different risk groups during from 2001 to 2010: 139 adults attended in an Emergency Room Patients (ERP); 205 health care workers (HCW); 69 from Renal Transplant Outpatients (RTO); 230 patients in hematopoietic stem cell transplantation (HSCT) program. RESULTS: Among all patients (n=643) adenovirus was detected on 13.2% by DFA and/or PCR: 6/139 (4.3%) adults from ERP, 7/205 (3.4%) from HCW samples, 4/69 (5.8%) from RTO and 68/230 (29.5%) from HSCT patients. Nested PCR showed higher detection (10%) compared to DFA test (3.8%) (p < 0.001). HSCT patients presented significantly higher prevalence of HAdV infection. CONCLUSIONS: Adenovirus detection through nested-PCR assay was higher. However the inclusion of molecular method in laboratorial routine diagnostic should be evaluated considering the reality of each specific health service. .

A survey strategy for human respiratory syncytial virus detection among haematopoietic stem cell transplant patients: epidemiological and methodological analysis.

Human respiratory syncytial virus (HRSV) causes severe infections among children and immunocompromised patients. We compared HRSV infections among Haematopoietic Stem Cell Transplant program (HSCT) patients and children using direct immunofluorescence (DFA), point-of-care RSV Bio Easy® and a polymerase chain reaction (PCR) assay. Overall, 102 samples from HSCT patients and 128 from children obtained positivity rate of 18.6% and 14.1% respectively. PCR sensitivity was highest mainly on samples collected after five days of symptoms onset. A combination of both DFA and reverse transcriptase-PCR methods for HSCT high-risk patients is the best diagnostic flow for HRSV diagnosis among these patients.

A survey strategy for human respiratory syncytial virus detection among haematopoietic stem cell transplant patients: epidemiological and methodological analysis

Human respiratory syncytial virus (HRSV) causes severe infections among children and immunocompromised patients. We compared HRSV infections among Haematopoietic Stem Cell Transplant program (HSCT) patients and children using direct immunofluorescence (DFA), point-of-care RSV Bio Easy® and a polymerase chain reaction (PCR) assay. Overall, 102 samples from HSCT patients and 128 from children obtained positivity rate of 18.6% and 14.1% respectively. PCR sensitivity was highest mainly on samples collected after five days of symptoms onset. A combination of both DFA and reverse transcriptase-PCR methods for HSCT high-risk patients is the best diagnostic flow for HRSV diagnosis among these patients.

Severe metapneumovirus infections among immunocompetent and immunocompromised patients admitted to hospital with respiratory infection.

Human metapneumovirus (hMPV) is considered an important cause of acute respiratory infections. hMPV can cause morbidity in hematopoietic stem cell transplant recipients and recent research has demonstrated that it is an important virus in patients admitted to hospital with respiratory infections and suspected of having pandemic 2009 influenza A (H1N1pdm09) virus. The purpose of this study was to investigate infections caused by hMPV in two groups of patients admitted to hospital: Immunocompromized patients with a potential risk of severe outcomes and immunocompetent patients with severe acute respiratory syndrome. A total of 288 samples were tested: 165 samples were collected from patients with suspected influenza A (H1N1) pdm09 infection during the first pandemic wave in 2009; and 123 samples were collected from patients of a hematopoietic stem cell transplantation program in 2008-2009. Amplification of the hMPV genes was performed by polymerase chain reaction. This was followed by sequencing and phylogenetic analysis. hMPV was detected in 14.2% (41/288) of all samples: 17% (28/165) of immunocompetent patients with suspected H1N1 infection and 10.6% (13/123) among hematopoietic stem cell transplant recipients. hMPV accounted for 12.1% (8/66) of immunocompetent adults patients with severe respiratory infections (median age, 55.9 years). Two hMPV subtypes were identified, A2 (26.9%; 7/26) and B2 (73.1%; 19/26) but no difference was observed between the patient groups in terms of age or immunosuppression level. This study highlights the significance of hMPV in immunocompetent adult patients with severe infections and further investigations are recommended for understanding the impact of this virus.