Mortalidad por Influenza pA(H1N1) 2009 en el noreste de México / Mortality from pandemic influenza A (H1N1) in northeast of Mexico

Objetivo. Determinar los factores asociados a la mortalidad por influenzapA(H1N1) en los pacientes hospitalizados por infección respiratoria agudagrave (IRAG) confirmada por reacción en cadena de la polimerasa (PCR)en el Instituto Mexicano del Seguro Social (IMSS).Material y métodos. En el IMSS en la delegación de Nuevo León entre el1 de junio de 2009 y 9 de marzo de 2010 se realizó un estudio observacionalretrospectivo de casos y controles, utilizando la base de datos del Sistemade Información en Línea para la Vigilancia Epidemiológica de Influenza(SINOLAVE). Se incluyeron 278 pacientes hospitalizados con IRAG (controles)y 50 pacientes con IRAG que fallecieron (casos) debido a la infecciónpor virus influenza pA(H1N1).Resultados. Los factores asociados a la mortalidad en los pacientes hospitalizadospor IRAG debida a influenza pA(H1N1) fueron la edad (OR: 1,03IC95% 1,01-1,05) y la obesidad (OR: 4,44 IC95% 1,85-1,6), utilizando unmodelo de regresión logística.Conclusión. Podemos concluir que en la delegación de Nuevo León delIMSS, la influenza pA(H1N1) afectó principalmente a adultos jóvenes, sinembargo las muertes se presentaron en mayor número en los pacientes alincrementar la edad y en pacientes con alguna comorbilidad.Palabras clave: Influenza pandémica A(H1N1), mortalidad, infección respiratoriaaguda grave, factores de riesgo, razón de probabilidad.

Objective. To determine factors associated with mortality from pAinfluenzA(H1N1) – confirmed by polymerase chain reaction (PCR) – Inhospitalized patients with severe acute respiratory infection (SARI) in theMexican Social Security Institute (IMSS). Methods. In the IMSS in the Delegation of Nuevo Leon between June 1, 2009 and March9, 2010 a retrospective observational case-control study was conducted using the database ofOnline Information System for Epidemiological Surveillance of Influenza (SINOLAVE). 278inpatients with SARI (controls) and 50 SARI patients who died (cases) due to infection withinfluenza virus pA(H1N1) were included.Results. In the logistic regression model factors associated with mortality in patientshospitalized due to SARI pA influenzA(H1N1) were age (OR: 1.03 95% CI 1.01-1.05) andobesity (OR: 4.44 95 1.85 to 1%, 0.6).Conclusion. We can conclude that the delegation of Nuevo León of the IMSS, pAinfluenzA(H1N1) affects mainly young adults, though the deaths occurred in greater numbersin patients with increasing age and in patients with comorbidities.

Spontaneous reporting of adverse events following pandemic influenza A (H1N1) immunization in a reference center in the State of Sao Paulo, Brazil

Introduction This paper describes adverse events (AEs) temporally associated to the pandemic influenza A (H1N1) vaccine observed in a reference center in São Paulo, Brazil, during a 2010 mass vaccination campaign. Methods A retrospective study involving persons who sought medical care for AEs following influenza vaccination. Data were retrieved from medical records, vaccine AE notification forms, and a computerized system for immunobiological registration. Results Sixty-six vaccinees sought medical care for AEs after immunization. The most frequent AEs were fever, headache, myalgia, and pain at the injection site. No serious AEs were reported. Conclusions Few vaccinees spontaneously reported AEs to influenza A (H1N1) vaccine at this center. .

The characteristics, clinical manifestations and outcomes of pandemic influenza A (H1N1) 2009 in the elderly

Introduction The objetctive of this study was to evaluate the 2009 Pandemic Influenza A (H1N1) in the elderly and identify the clinical characteristics, mortality and prognostic factors of the infection in these patients. Methods This was an observational, retrospective study. Data were collected from the National Notifiable Diseases (SINAN), from the Brazilian Ministry of Health. Only patients 60 years old or more that had laboratory confirmed infections were included. The socio-demographic and clinical variables and outcomes were evaluated to compare mortality rates in the presence or absence of these factors. Results We included 93 patients in the study, 16.1% of whom died. The symptoms of cough and dyspnea, the use of the antiviral oseltamivir, influenza vaccine and comorbidities influenced the outcomes of cure or death. Chest radiography can aid in diagnosis. Conclusions Although relatively few elderly people were infected, this population presented high lethality that can be justified by the sum of clinical, physical and immunological factors in this population. Treatment with oseltamivir and vaccination against seasonal influenza have significantly reduced rates of hospitalization and mortality. .

Clinical and Laboratory Characteristics of Pandemic Influenza A/H1N1 2009 Infection among Patients with Malignancy in Korea / 감염과화학요법

BACKGROUND: Patients with malignancy are considered to be at high risk of severe pandemic influenza A/H1N1 2009. This study was conducted to identify the severity of pandemic influenza A/H1N1 2009 among patients with malignancy. MATERIALS AND METHODS: Between August 2009 and December 2009, we reviewed clinical data and medical records of 31 patients with malignancy and 63 hospitalized patients without malignancy. RESULTS: Eighty-three patients with laboratory-confirmed pandemic influenza A/H1N1 2009 were admitted. The rate of ICU admission was higher among patients with malignancy (without malignancy 13% vs with malignancy 35%, P=0.024). The mortality rate was higher among patients with malignancy (without malignancy 6% vs with malignancy 25%, P=0.033). Patients using immunosuppressants showed a higher rate of lower respiratory tract infection (83% vs 24%, P=0.013). CONCLUSIONS: Pandemic influenza A/H1N1 2009 in patients with malignancy was more severe than in patients without malignancy.

Characteristics of Hospitalized Children with 2009 Pandemic Influenza A (H1N1): A Multicenter Study in Korea

The majority of Korean patients with pandemic influenza A (H1N1) during the 2009 epidemic were under 20 yr of age. The limited data on the clinical characteristics of these children led us to conduct a case note-based investigation of children admitted to 6 university hospitals with 2009 H1N1 influenza. A total of 804 children was enrolled. The median age was 5 yr; 63.8% were males; and 22.4% had at least one chronic underlying disease. Ninety-five of the patients (11.8%) were critically ill and they suffered more from shortness of breath, dyspnea and lymphopenia than the other patients. Among all the patients, 98.8% were treated with antivirals and 73% received treatment within 48 hr of illness onset. All the enrolled patients are alive and appear to have had good outcomes, probably due to the early intervention and antiviral treatment. This study deals with hospitalized children whose diagnoses of influenza A (H1N1) were confirmed, and therefore provides important new information about the clinical patterns of children with influenza A (H1N1) in Korea.

2009 Pandemic Influenza A(H1N1) Infections in the Pediatric Cancer Patients and Comparative Analysis with Seasonal Influenza / 소아감염

PURPOSE: This study was performed to compare the clinical characteristics of 2009 pandemic influenza A(H1N1) [A(H1N1) pdm09] and seasonal influenza A infection in the pediatric cancer patients. METHODS: A retrospective review was performed in the pediatric cancer patients who had confirmed A(H1N1)pdm09 infection at Samsung Medical Center from August 2009 to February 2010. For the comparison, the medical records of pediatric cancer patients with seasonal influenza A from January 2000 to May 2009 were reviewed retrospectively. RESULTS: Eighty-two A(H1N1)pdm09 infections were confirmed in the pediatric cancer patients. Ten patients (12.2%) developed complicated clinical course by lower respiratory infections or extrapulmonary infections; 4 pneumonia, 1 bronchitis, 1 pericarditis with pneumonia, 1 encephalitis with pneumonia, 2 meningitis and 1 pericarditis. Three patients received mechanical ventilator and ICU care. Three pediatric cancer patients (3.7%) died. The risk factors related to complicated A(H1N1)pdm09 infections were date of infection (44-45th week 2009) and nosocomial infection. When comparing with previous seasonal influenza A infections, more prompt and aggressive antiviral therapy was given in A(H1N1)pdm09 infections. CONCLUSION: The A(H1N1)pdm09 infections caused a various clinical manifestations including fatal cases in pediatric cancer patient during pandemic season. There was no significant difference in clinical course between influenza A(H1N1)pdm09 and seasonal influenza A infections except the antiviral treatment strategy.

Epidemiological Characteristics of Imported Influenza A (H1N1) Cases during the 2009 Pandemic in Korea / 한국역학회지

OBJECTIVES: Quarantine measure for prevention of epidemic disease and further evaluations of their efficiency are possible only by elaborating analyses of imported cases. The purpose of this study was to analyze descriptive epidemiological characteristics of pandemic influenza A (H1N1) cases imported to Korea. METHODS: We collected two sets of data. The first set, comprised daily reported cases of H1N1 obtained from local cities in accordance with government policy about mandatory reporting of all H1N1 cases during May 1 to August 19, 2009. The second set, including 372 confirmed imported H1N1 cases, identified from 13 National Quarantine Stations in the Korea Centers for Disease Control and Prevention from May 24 to December 31, 2009. However, given the lack of information on the nature of the imported H1N1 cases from the two data sets during the over lapping period from May 24 to August 19, we express the number of imported cases as a range for this period. RESULTS: We estimated that the number of imported H1N1 cases from May 1 to August 19, 2009, was between 1,098 and 1,291 and the total number of cases was 2,409 to 2,580. We found the number of imported cases was beginning to diminish as of August. A analysis of the second data set showed that the distribution of sex was similar (males 50.7%, females 49.3%) and the age distribution from 20 to 59 was 61.5% and that of 60 and over was 0.8% of the 372 cases. We identified 25 countries where people infected with H1N1 traveled and 67.5% were in Asia. But the proportion of cases (/1,000) by region shows Oceania (0.199), South America (0.118), Southeast Asia (0.071), North America (0.049), Europe (0.035), and Northeast Asia (0.016) in that order. The order of H1N1 peaking was the Southern Hemisphere, Tropics, and the Nothern Hemisphere. CONCLUSIONS: This study provided information that could make possible the evaluation of the government quarantine measure for stopping imported disease from causing community-acquired spread in the future.

Diseño y aplicación de un método molecular para el diagnóstico del virus influenza A (H1N1) pandémico en Cuba / Design and implementation of a molecular method for influenza A virus (H1N1) in Cuba

INTRODUCCIÓN: entre marzo y abril de 2009 se produjeron en México brotes de enfermedad respiratoria, debido a un nuevo virus de influenza proveniente del cerdo, el cual se diseminó rápidamente mediante la transmisión humano-humano. Los métodos moleculares usados en la actualidad eran inadecuados, porque la composición del genoma del nuevo virus era muy diferente del virus influenza A (H1N1) que había circulado hasta el momento. En su composición, estaba formado por segmentos de genes de origen aviar, humano y cerdo. OBJETIVO: teniendo en cuenta las secuencias publicadas, se diseñó un juego de cebadores específicos para el gen de la hemaglutinina, con la finalidad de evaluar un nuevo ensayo de TR-RCP para detectar el nuevo virus pandémico en Cuba. MÉTODOS: se procesó un total de 3 197 muestras clínicas de casos sospechosos de infección por el virus influenza A (H1N1) pandémico (pdm) mediante un ensayo de transcripción reversa-reacción en cadena de la polimerasa. RESULTADOS: el ensayo optimizado permitió obtener una banda de 292 pb, sin reacciones inespecíficas. El nuevo método resultó ser útil en el diagnóstico y subtipado del virus de influenza H1N1 pdm. El producto amplificado fue analizado por secuenciación nucleotídica y se confirmó la identificación del virus. CONCLUSIONES: con la introducción de este nuevo ensayo para la vigilancia de influenza, se fortalece la capacidad diagnóstica del Laboratorio Nacional de Referencia.

INTRODUCTION: from March through April of 2009, Mexico notified outbreaks of respiratory illness, due to a new influenza virus of swine origin, which spread over rapidly via human-to-human transmission. The molecular methods currently in use were not suitable because the genome composition based on gene segments of swine, avian and human origin was quite different from the influenza A virus (H1N1) circulating at that time. OBJECTIVE: based on the published sequences, a set of specific primers for the HA gene was designed to evaluate a new RT-PCR assay. METHODS: the RT-PCR assay processed 3 197 clinical samples from suspected cases of pandemic influenza A (H1N1) infection. RESULTS: the novel optimized method obtained a 262 pb segment, without unspecific reactions. The new method proved to be useful in the diagnosis and subtyping of pandemic HINI influenza virus. The amplified product was verified by nucleotide sequencing, thus confirming the virus. CONCLUSIONS: the introduction of this new assay for the laboratory surveillance of influenza virus strengthens the diagnostic capacity of the National Reference Laboratory.

A Prediction Rule to Identify Severe Cases among Adult Patients Hospitalized with Pandemic Influenza A (H1N1) 2009

The purpose of this study was to establish a prediction rule for severe illness in adult patients hospitalized with pandemic influenza A (H1N1) 2009. At the time of initial presentation, the baseline characteristics of those with severe illness (i.e., admission to intensive care unit, mechanical ventilation, or death) were compared to those of patients with non-severe illnesses. A total of 709 adults hospitalized with pandemic influenza A (H1N1) 2009 were included: 75 severe and 634 non-severe cases. The multivariate analysis demonstrated that altered mental status, hypoxia (PaO2/FiO2 or = 65 yr) were independent risk factors for severe cases (all P or = 2 risk factors had a higher sensitivity, specificity, positive predictive value and negative predictive value than an APACHE II score of > or = 13. As a prediction rule, the presence of > or = 2 these risk factors is a powerful and easy-to-use predictor of the severity in adult patients hospitalized with pandemic influenza A (H1N1) 2009.

The Influence of Atopic Findings on Severity of Pneumonia in Children with 2009 Pandemic Influenza A (H1N1) Infection / 소아감염

PURPOSE: Atopic findings may be associated with severity of pneumonia in 2009 pandemic influenza A (H1N1) infection, which could suggest a possible association between atopic findings and the severity of viral infections. Thus, we studied association between atopic findings and severity of disease in children with H1N1 influenza infection. METHODS: A retrospective study was performed in 74 children admitted in a single tertiary institute and confirmed as H1N1 patients by reverse transcriptase (RT) - polymerase chain reaction (PCR). They were divided into 2 groups according to the severity of pneumonia. We evaluated whether the atopic finding is risk factor between the two groups. RESULTS: Children with severe pneumonia had higher percentages of serum eosinophilia (88% vs 40%, P<0.001), asthma (65% vs 35%, P=0.011), allergic rhinitis (71% vs 40%, P=0.009), and IgE level (P=0.007). We found positive correlations between aeroallergen sensitizations and severity of pneumonia (82% vs 53%, P=0.007). CONCLUSION: Among patients with H1N1 pneumonia, asthma and atopic findings are risk factors for severity of pneumonia.

Management of Healthcare Workers and Patients on Exposure to Pandemic Influenza A (H1N1 2009) Virus in a Hospital / 병원감염관리

BACKGROUND: This study is aimed at describing the outcomes of the management of the patients, caregivers, and healthcare workers (HCWs) who are exposed to the pandemic influenza (H1N1 2009) virus and at evaluating the adequacy in exposure management and infection control. METHODS: From July 2009 to January 2010, for 7 a month period, we managed patients and healthcare workers without any respiratory protective devices, who came within 1 m distance of H1N1-positive individuals for more than 1 h and performed a 1-week follow-up. RESULTS: The total of 157 cases with exposure to pandemic influenza (H1N1 2009) virus and exposed individuals of 907 were reported. Of the exposed individuals who were under management, 15 were confirmed to be infected with the infection rate being 1.7%. The confirmed individuals did not have a secondary infection after the exposure. Rates of infection of the exposed patients and healthcare workers were 1.8% and 1.6%, respectively, and these figures were not statistically significant. CONCLUSION: The exposure management results at the hospital revealed that the infection had spread by contact with individuals who were positive for the infection. The high incidence of early exposure to the virus warrants the need to ensure the use of protective equipment and the adoption of assertive teaching methods that have long lasting effects.

Quantitative evaluation on the effectiveness of prevention and control measures against pandemic influenza A (H1N1) in Beijing, 2009 / 中华流行病学杂志

Objective To quantitatively evaluate the effectiveness of prevention and control measures against pandemic influenza A (H1N1) in Beijing, 2009 and to provide evidence for developing and adjusting strategies for prevention and control of the disease. Methods Considering the seasonality and the number of vaccination on pandemic influenza A (H1N1) , data regarding pandemic influenza A (H1N1) in Beijing were collected and analyzed. Based on the dynamics of infectious disease transmission, a quantitative model for evaluation of prevention and control measures was developed. Results Both latency and infectious periods of pandemic influenza A (H1N1) were estimated to be 1.82 days and 2.08 days, respectively. The effective reproduction numbers of the three periods were 1.13,1.65 and 0.96, respectively. Thanks to the implementation of a series of measures to prevent and control pandemic influenza A (H1N1), the cumulative number of laboratory-confirmed cases of pandemic influenza A (H1N1) was reduced, making it much smaller than what would have been under the natural situation. Specifically, the program on pandemic (H1N1) 2009 vaccination reduced the cumulative number of laboratory-confirmed cases by 24.08% and postponed the peak time. Conclusion Measures that had been taken during this period, had greatly contributed to the successful prevention and control of pandemic influenza A (H1N1). The 2009 Pandemic (H1N1)vaccination was confirmed to have contributed to the decrease of cumulative number of laboratoryconfirmed cases and postponed the peak arrival time.

Serologic survey on pandemic influenza A (H1N1) virus among aged ≥3 years population from Jiangsu province in 2009, China / 中华流行病学杂志

Objective To understand the antibody levels against pandemic influenza A (H1N1) virus (2009 H1N1 ) among aged ≥3 years population in 2009, from Jiangsu province, and to describe the distribution of 2009 H1N1. Methods Serum specimens were collected from natural populations at four different periods in Jiangsu, and tested with hernagglutination-inhibition (HI)assays. Rates of protective antibody against 2009 H1N1 and Geometric mean titers (GMTs)were estimated. Results The rates of protective antibody against 2009 H1N1 rose with the and November, 2009. There were no significant differences on the rates of protective antibody between males and females at four different cross-sectional periods (P＞0.05), and no significant differences on GMTs were observed at different periods except for November 2009. Significant differences on rates of protective antibody and GMTs among various age groups were observed at four different periods (P＜0.05), and similar results were observed among different periods in various age groups (P＜0.05). There were significant differences on rates of protective antibody and GMTs among different areas (P＜0.05). Conclusion The 2009 H1N1 strain had been widely spread out in Jiangsu province since July 2009. People aged 12-17 years became the major victims after August. As of November 2009, the rate of protective antibody against 2009 H1N1 was still low, predicting that the epidemic might continue to exist for a certain period of time.