Showing papers by "Timothy M. Uyeki published in 2009"

Emergence of a novel swine-origin influenza A (H1N1) virus in humans.

Abstract: Enhanced surveillance was implemented in the United States for human infection with influenza A viruses that could not be subtyped. Specimens were sent to the Centers for Disease Control and Prevention for real-time reverse-transcriptase–polymerase-chain-reaction confirmatory testing for S-OIV. RESULTS From April 15 through May 5, a total of 642 confirmed cases of S-OIV infection were identified in 41 states. The ages of patients ranged from 3 months to 81 years; 60% of patients were 18 years of age or younger. Of patients with available data, 18% had recently traveled to Mexico, and 16% were identified from school outbreaks of S-OIV infection. The most common presenting symptoms were fever (94% of patients), cough (92%), and sore throat (66%); 25% of patients had diarrhea, and 25% had vomiting. Of the 399 patients for whom hospitalization status was known, 36 (9%) required hospitalization. Of 22 hospitalized patients with available data, 12 had characteristics that conferred an increased risk of severe seasonal influenza, 11 had pneumonia, 8 required admission to an intensive care unit, 4 had respiratory failure, and 2 died. The S-OIV was determined to have a unique genome composition that had not been identified previously. CONCLUSIONS A novel swine-origin influenza A virus was identified as the cause of outbreaks of febrile respiratory infection ranging from self-limited to severe illness. It is likely that the number of confirmed cases underestimates the number of cases that have occurred.

Antigenic and Genetic Characteristics of Swine-Origin 2009 A(H1N1) Influenza Viruses Circulating in Humans

Abstract: Since its identification in April 2009, an A(H1N1) virus containing a unique combination of gene segments from both North American and Eurasian swine lineages has continued to circulate in humans. The lack of similarity between the 2009 A(H1N1) virus and its nearest relatives indicates that its gene segments have been circulating undetected for an extended period. Its low genetic diversity suggests that the introduction into humans was a single event or multiple events of similar viruses. Molecular markers predictive of adaptation to humans are not currently present in 2009 A(H1N1) viruses, suggesting that previously unrecognized molecular determinants could be responsible for the transmission among humans. Antigenically the viruses are homogeneous and similar to North American swine A(H1N1) viruses but distinct from seasonal human A(H1N1).

Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2009.

Abstract: This report updates the 2009 recommendations by CDC's Advisory Committee on Immunization Practices (ACIP) regarding the use of influenza vaccine for the prevention and control of influenza (CDC. Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices [ACIP]. MMWR 2009;58[No. RR-8] and CDC. Use of influenza A (H1N1) 2009 monovalent vaccine---recommendations of the Advisory Committee on Immunization Practices [ACIP], 2009. MMWR 2009;58:[No. RR-10]). The 2010 influenza recommendations include new and updated information. Highlights of the 2010 recommendations include 1) a recommendation that annual vaccination be administered to all persons aged >or=6 months for the 2010-11 influenza season; 2) a recommendation that children aged 6 months--8 years whose vaccination status is unknown or who have never received seasonal influenza vaccine before (or who received seasonal vaccine for the first time in 2009-10 but received only 1 dose in their first year of vaccination) as well as children who did not receive at least 1 dose of an influenza A (H1N1) 2009 monovalent vaccine regardless of previous influenza vaccine history should receive 2 doses of a 2010-11 seasonal influenza vaccine (minimum interval: 4 weeks) during the 2010--11 season; 3) a recommendation that vaccines containing the 2010-11 trivalent vaccine virus strains A/California/7/2009 (H1N1)-like (the same strain as was used for 2009 H1N1 monovalent vaccines), A/Perth/16/2009 (H3N2)-like, and B/Brisbane/60/2008-like antigens be used; 4) information about Fluzone High-Dose, a newly approved vaccine for persons aged >or=65 years; and 5) information about other standard-dose newly approved influenza vaccines and previously approved vaccines with expanded age indications. Vaccination efforts should begin as soon as the 2010-11 seasonal influenza vaccine is available and continue through the influenza season. These recommendations also include a summary of safety data for U.S.-licensed influenza vaccines. These recommendations and other information are available at CDC's influenza website (http://www.cdc.gov/flu); any updates or supplements that might be required during the 2010-11 influenza season also will be available at this website. Recommendations for influenza diagnosis and antiviral use will be published before the start of the 2010-11 influenza season. Vaccination and health-care providers should be alert to announcements of recommendation updates and should check the CDC influenza website periodically for additional information.

Hospitalized patients with 2009 H1N1 influenza in the United States, April-June 2009.

Abstract: BACKGROUND During the spring of 2009, a pandemic influenza A (H1N1) virus emerged and spread globally. We describe the clinical characteristics of patients who were hospitalized with 2009 H1N1 influenza in the United States from April 2009 to mid-June 2009. METHODS Using medical charts, we collected data on 272 patients who were hospitalized for at least 24 hours for influenza-like illness and who tested positive for the 2009 H1N1 virus with the use of a real-time reverse-transcriptase-polymerase-chain-reaction assay. RESULTS Of the 272 patients we studied, 25% were admitted to an intensive care unit and 7% died. Forty-five percent of the patients were children under the age of 18 years, and 5% were 65 years of age or older. Seventy-three percent of the patients had at least one underlying medical condition; these conditions included asthma; diabetes; heart, lung, and neurologic diseases; and pregnancy. Of the 249 patients who underwent chest radiography on admission, 100 (40%) had findings consistent with pneumonia. Of the 268 patients for whom data were available regarding the use of antiviral drugs, such therapy was initiated in 200 patients (75%) at a median of 3 days after the onset of illness. Data suggest that the use of antiviral drugs was beneficial in hospitalized patients, especially when such therapy was initiated early. CONCLUSIONS During the evaluation period, 2009 H1N1 influenza caused severe illness requiring hospitalization, including pneumonia and death. Nearly three quarters of the patients had one or more underlying medical conditions. Few severe illnesses were reported among persons 65 years of age or older. Patients seemed to benefit from antiviral therapy.

Seasonal Influenza in Adults and Children—Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management: Clinical Practice Guidelines of the Infectious Diseases Society of America

Abstract: Guidelines for the treatment of persons with influenza virus infection were prepared by an Expert Panel of the Infectious Diseases Society of America. The evidence-based guidelines encompass diagnostic issues, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal (interpandemic) influenza. They are intended for use by physicians in all medical specialties with direct patient care, because influenza virus infection is common in communities during influenza season and may be encountered by practitioners caring for a wide variety of patients.

Triple-Reassortant Swine Influenza A (H1) in Humans in the United States, 2005–2009

Abstract: Background Triple-reassortant swine influenza A (H1) viruses — containing genes from avian, human, and swine influenza viruses — emerged and became enzootic among pig herds in North America during the late 1990s. Methods We report the clinical features of the first 11 sporadic cases of infection of humans with triple-reassortant swine influenza A (H1) viruses reported to the Centers for Disease Control and Prevention, occurring from December 2005 through February 2009, until just before the current epidemic of swine-origin influenza A (H1N1) among humans. These data were obtained from routine national influenza surveillance reports and from joint case investigations by public and animal health agencies. Results The median age of the 11 patients was 10 years (range, 16 months to 48 years), and 4 had underlying health conditions. Nine of the patients had had exposure to pigs, five through direct contact and four through visits to a location where pigs were present but without contact. In another patient, hu...

Facemasks and hand hygiene to prevent influenza transmission in households: a cluster randomized trial.

Abstract: Background Few data are available about the effectiveness of nonpharmaceutical interventions for preventing influenza virus transmission. Objective To investigate whether hand hygiene and use of facemasks prevents household transmission of influenza. Design Cluster randomized, controlled trial. Randomization was computer generated; allocation was concealed from treating physicians and clinics and implemented by study nurses at the time of the initial household visit. Participants and personnel administering the interventions were not blinded to group assignment. (ClinicalTrials.gov registration number: NCT00425893) Setting Households in Hong Kong. Patients 407 people presenting to outpatient clinics with influenza-like illness who were positive for influenza A or B virus by rapid testing (index patients) and 794 household members (contacts) in 259 households. Intervention Lifestyle education (control) (134 households), hand hygiene (136 households), or surgical facemasks plus hand hygiene (137 households) for all household members. Measurements Influenza virus infection in contacts, as confirmed by reverse-transcription polymerase chain reaction (RT-PCR) or diagnosed clinically after 7 days. Results Sixty (8%) contacts in the 259 households had RT-PCR-confirmed influenza virus infection in the 7 days after intervention. Hand hygiene with or without facemasks seemed to reduce influenza transmission, but the differences compared with the control group were not significant. In 154 households in which interventions were implemented within 36 hours of symptom onset in the index patient, transmission of RT-PCR-confirmed infection seemed reduced, an effect attributable to fewer infections among participants using facemasks plus hand hygiene (adjusted odds ratio, 0.33 [95% CI, 0.13 to 0.87]). Adherence to interventions varied. Limitation The delay from index patient symptom onset to intervention and variable adherence may have mitigated intervention effectiveness. Conclusion Hand hygiene and facemasks seemed to prevent household transmission of influenza virus when implemented within 36 hours of index patient symptom onset. These findings suggest that nonpharmaceutical interventions are important for mitigation of pandemic and interpandemic influenza. Primary funding source Centers for Disease Control and Prevention.

Intensive-care patients with severe novel influenza A (H1N1) virus infection - Michigan, June 2009.

Abstract: In April 2009, CDC reported the first two cases in the United States of human infection with a novel influenza A (H1N1) virus. As of July 6, a total of 122 countries had reported 94,512 cases of novel influenza A (H1N1) virus infection, 429 of which were fatal; in the United States, a total of 33,902 cases were reported, 170 of which were fatal. Cases of novel influenza A (H1N1) virus infection have included rapidly progressive lower respiratory tract disease resulting in respiratory failure, development of acute respiratory distress syndrome (ARDS), and prolonged intensive care unit (ICU) admission. Since April 26, communitywide transmission of novel influenza A (H1N1) virus has occurred in Michigan, with 655 probable and confirmed cases reported as of June 18 (Michigan Department of Community Health [MDCH], unpublished data, 2009). This report summarizes the clinical characteristics of a series of 10 patients with novel influenza A (H1N1) virus infection and ARDS at a tertiary-care ICU in Michigan. Of the 10 patients, nine were obese (body mass index [BMI] >or=30), including seven who were extremely obese (BMI =40); five had pulmonary emboli; and nine had multiorgan dysfunction syndrome (MODS). Three patients died. Clinicians should be aware of the potential for severe complications of novel influenza A (H1N1) virus infection, particularly in extremely obese patients.

Influenza estacional en adultos y niños—Diagnóstico, tratamiento, quimioprofilaxis y control de brotes institucionales: Guías de práctica clínica de la Sociedad de Enfermedades Infecciosas de Estados Unidos de América

Abstract: 14 Universidad de Toronto, Ontario, Canada. Es importante advertir que, en las guo´as, no es posible tener en cuenta siempre las variaciones individuales que se presenten entre pacientes. Las guo´as no intentan reemplazar el criterio del medico respecto de pacientes en particular o cuadros clo´nicos especiales. La Sociedad de Enfermedades Infecciosas de Estados Unidos de America considera que la adhesion a estas guo´as es voluntaria y que la determinacion final sobre su aplicacion corresponde al medico conforme a la situacion individual de cada paciente. Los hallazgos y las conclusiones de este informe pertenecen a los autores y no representan, necesariamente, la postura oficial de los Centros para el Control y Prevencion de Enfermedades.

Evaluation of rapid influenza diagnostic tests for detection of novel influenza A (H1N1) virus - United States, 2009.

Abstract: The recent appearance and worldwide spread of novel influenza A (H1N1) virus has highlighted the need to evaluate commercially available, widely used, rapid influenza diagnostic tests (RIDTs) for their ability to detect these viral antigens in respiratory clinical specimens. As an initial assessment, CDC conducted an evaluation of multiple RIDTs. Sixty-five clinical respiratory specimens collected during April-May 2009 that had previously tested positive either for novel influenza A (H1N1) or for seasonal influenza A (H1N1) or A (H3N2) viruses by real-time reverse transcription--polymerase chain reaction (rRT-PCR) assay were used in the evaluation. The results showed that, although the RIDTs were capable of detecting novel A (H1N1) virus from respiratory specimens containing high levels of virus (as indicated by low cycle threshold [Ct] values), the overall sensitivity was low (40%-69%) among all specimens tested and declined substantially as virus levels decreased (and Ct values increased). These findings indicate that, although a positive RIDT result can be used in making treatment decisions, a negative result does not rule out infection with novel influenza A (H1N1) virus. Patients with illnesses compatible with novel influenza A (H1N1) virus infection but with negative RIDT results should be treated empirically based on the level of clinical suspicion, underlying medical conditions, severity of illness, and risk for complications. If a more definitive determination of infection with influenza virus is required, testing with rRT-PCR or virus isolation should be performed. Additional evaluations of the accuracy of RIDTs in detecting novel influenza A (H1N1) virus should be conducted.

Low Sensitivity of Rapid Diagnostic Test for Influenza

Abstract: The QuickVue Influenza A+B Test (Quidel) was used to test nasal swab specimens obtained from persons with influenzalike illness in 3 different populations. Compared with reverse-transcriptase polymerase chain reaction, the test sensitivity was low for all populations (median, 27%; range, 19%‐32%), whereas the specificity was high (median, 97%; range, 96%‐99.6%).

Neurologic complications associated with novel influenza A (H1N1) Virus infection in children - Dallas, Texas, May 2009.

Abstract: Neurologic complications, including seizures, encephalitis, encephalopathy, Reye syndrome, and other neurologic disorders, have been described previously in association with respiratory tract infection with seasonal influenza A or B viruses, but not with novel influenza A (H1N1) virus. On May 28, 2009, the Dallas County Department of Health and Human Services (DCHHS) notified CDC of four children with neurologic complications associated with novel influenza A (H1N1) virus infection admitted to hospitals in Dallas County, Texas, during May 18-28. This report summarizes the clinical characteristics of those four cases. Patients were aged 7-17 years and were admitted with signs of influenza-like illness (ILI) and seizures or altered mental status. Three of the four patients had abnormal electroencephalograms (EEGs). In all four patients, novel influenza A (H1N1) viral RNA was detected in nasopharyngeal specimens but not in cerebrospinal fluid (CSF). Antiviral therapy included oseltamivir (four patients) and rimantadine (three patients). All four patients recovered fully and had no neurologic sequelae at discharge. These findings indicate that, as with seasonal influenza, neurologic complications can occur after respiratory tract infection with novel influenza A (H1N1) virus. For children who have ILI accompanied by unexplained seizures or mental status changes, clinicians should consider acute seasonal influenza or novel influenza A (H1N1) virus infection in the differential diagnosis, send respiratory specimens for appropriate diagnostic testing, and promptly initiate empirical antiviral treatment, especially in hospitalized patients.

Incidence, seasonality and mortality associated with influenza pneumonia in Thailand: 2005-2008.

Abstract: Background Data on the incidence, seasonality and mortality associated with influenza in subtropical low and middle income countries are limited. Prospective data from multiple years are needed to develop vaccine policy and treatment guidelines, and improve pandemic preparedness. Methods During January 2005 through December 2008, we used an active, population-based surveillance system to prospectively identify hospitalized pneumonia cases with influenza confirmed by reverse transcriptase–polymerase chain reaction or cell culture in 20 hospitals in two provinces in Thailand. Age-specific incidence was calculated and extrapolated to estimate national annual influenza pneumonia hospital admissions and in-hospital deaths. Results Influenza was identified in 1,346 (10.4%) of pneumonia patients of all ages, and 10 influenza pneumonia patients died while in the hospital. 702 (52%) influenza pneumonia patients were less than 15 years of age. The average annual incidence of influenza pneumonia was greatest in children less than 5 years of age (236 per 100,000) and in those age 75 or older (375 per 100,000). During 2005, 2006 and 2008 influenza A virus detection among pneumonia cases peaked during June through October. In 2007 a sharp increase was observed during the months of January through April. Influenza B virus infections did not demonstrate a consistent seasonal pattern. Influenza pneumonia incidence was high in 2005, a year when influenza A(H3N2) subtype virus strains predominated, low in 2006 when A(H1N1) viruses were more common, moderate in 2007 when H3N2 and influenza B co-predominated, and high again in 2008 when influenza B viruses were most common. During 2005–2008, influenza pneumonia resulted in an estimated annual average 36,413 hospital admissions and 322 in-hospital pneumonia deaths in Thailand. Conclusion Influenza virus infection is an important cause of hospitalized pneumonia in Thailand. Young children and the elderly are most affected and in-hospital deaths are more common than previously appreciated. Influenza occurs year-round and tends to follow a bimodal seasonal pattern with substantial variability. The disease burden varies significantly from year to year. Our findings support a recent Thailand Ministry of Public Health (MOPH) decision to extend annual influenza vaccination to older adults and suggest that children should also be targeted for routine vaccination.

Human Infection with Highly Pathogenic Avian Influenza A (H5N1) Virus: Review of Clinical Issues

Abstract: This article provides an updated review of the clinical issues related to human infection with highly pathogenic avian influenza A (H5N1) virus. The clinical data available to date are presented, as well as recent findings on the pathogenesis of and antiviral treatment and immunotherapy for H5N1 virus infection in humans and animal models.

Update: novel influenza A (H1N1) virus infection - Mexico, March-May 2009.

Abstract: On April 12, 2009, Mexico responded to a request for verification by the World Health Organization (WHO) of an outbreak of acute respiratory illness in the small community of La Gloria, Veracruz. During April 15-17, the Mexico Ministry of Health received informal notification of clusters of rapidly progressive severe pneumonia occurring mostly in Distrito Federal (metropolitan Mexico City) and San Luis Potosi. In response, on April 17, Mexico intensified national surveillance for acute respiratory illness and pneumonia. During April 22-24, novel influenza A (H1N1) virus infection, previously identified in two children in the United States, was confirmed in several patients. This report updates a previous report on the outbreak in Mexico and summarizes public health actions taken to date by Mexico to monitor and control the outbreak. During March 1-May 29, national surveillance identified 41,998 persons with acute respiratory illness; specimens from 25,127 (59.8%) patients were tested, of which 5,337 (21.2%) were positive for novel influenza A (H1N1) virus infection by real-time reverse transcription--polymerase chain reaction (rRT-PCR). As of May 29, 97 patients with laboratory-confirmed infection had died. Epidemiologic evidence to date suggests that the outbreak likely peaked nationally in late April, although localized cases continue to be identified.

Novel influenza A (H1N1) virus infections in three pregnant women - United States, April-May 2009.

Abstract: CDC first identified cases of respiratory infection with a novel influenza A (H1N1) virus in the United States on April 15 and 17, 2009. During seasonal influenza epidemics and previous pandemics, pregnant women have been at increased risk for complications related to influenza infection. In addition, maternal influenza virus infection and accompanying hyperthermia place fetuses at risk for complications such as birth defects and preterm birth. As part of surveillance for infection with the novel influenza A (H1N1) virus, CDC initiated surveillance for pregnant women who were infected with the novel virus. As of May 10, a total of 20 cases of novel influenza A (H1N1) virus infection had been reported among pregnant women in the United States, including 15 confirmed cases and five probable cases. Among the 13 women from seven states for whom data are available, the median age was 26 years (range: 15-39 years); three women were hospitalized, one of whom died. This report provides preliminary details of three cases of novel influenza A (H1N1) virus infection in pregnant women. Pregnant women with confirmed, probable, or suspected novel influenza A (H1N1) virus infection should receive antiviral treatment for 5 days. Oseltamivir is the preferred treatment for pregnant women, and the drug regimen should be initiated within 48 hours of symptom onset, if possible. Pregnant women who are in close contact with a person with confirmed, probable, or suspected novel influenza A (H1N1) infection should receive a 10-day course of chemoprophylaxis with zanamivir or oseltamivir.

Risk Factors for Human Illness with Avian Influenza A (H5N1) Virus infection in China

Abstract: Background. InChina,30humancasesofavianinfluenzaA(H5N1)virusinfectionwereidentifiedthroughJuly 2008. We conducted a retrospective case-control study to identify risk factors for influenza H5N1 disease in China. Methods. A questionnaire about potential influenza H5N1 exposures was administered to 28 patients with influenza H5N1 and to 134 randomly selected control subjects matched by age, sex, and location or to proxies. Conditional logistic regression analyses were performed. Results. Before their illness, patients living in urban areas had visited wet poultry markets, and patients living in rural areas had exposure to sick or dead backyard poultry. In multivariable analyses, independent risk factors for influenza H5N1 were direct contact with sick or dead poultry (odds ratio [OR], 506.6 [95% confidence interval {CI}, 15.7‐16319.6]; P .001),indirect exposure to sick or dead poultry (OR, 56.9 [95% CI, 4.3‐745.6]; P .002), and visiting a wet poultry market (OR, 15.4 [95% CI, 3.0‐80.2]; P .001). Conclusions. To prevent human influenza H5N1 in China, the level of education about avoiding direct or close exposures to sick or dead poultry should be increased, and interventions to prevent the spread of influenza H5N1 at live poultry markets should be implemented. In parallel with the unprecedented epizootic of highly pathogenicavianinfluenzaA(H5N1)virusesamongpoultryandmigratorybirds[1],418confirmedhumancasesof

Risk Factors Associated with Subclinical Human Infection with Avian Influenza A (H5N1) Virus―Cambodia, 2006

Abstract: BACKGROUND: We conducted investigations in 2 villages in Cambodia where outbreaks of influenza H5N1 occurred among humans and poultry to determine the frequency of and risk factors for H5N1 virus transmission. METHODS: During May 2006, approximately 7 weeks after outbreaks of influenza H5N1 among poultry occurred, villagers living near households of 2 patients with influenza H5N1 were interviewed about potential H5N1 exposures and had blood samples obtained for H5N1 serological testing by microneutralization assay. A seropositive result was defined as an influenza H5N1 neutralizing antibody titer of 1:80, with confirmation by Western blot assay. A case-control study was conducted to identify risk factors for influenza H5N1 virus infection. Control subjects, who had seronegative results of tests, were matched with H5N1-seropositive persons by village residence, households with an influenza H5N1-infected poultry flock, sex, and age. RESULTS: Seven (1.0%) of 674 villagers tested seropositive for influenza H5N1 antibodies and did not report severe illness; 6 (85.7%) were male. The 7 H5N1-seropositive persons, all of whom were aged

Pandemic H1N1 and the 2009 Hajj

Abstract: The annual Hajj pilgrimage of more than 2.5 million pilgrims from more than 160 countries is held in the Kingdom of Saudi Arabia (KSA) ( 1 ) (see the figure). Hajj is a deeply spiritual journey undertaken by Muslims at least once in their lifetimes. Hajj-related infectious disease outbreaks in recent decades have focused attention on Hajj as a global public health security challenge of extraordinary dimensions ( 1 – 5 ). This past summer, a KSA–World Health Organization (WHO) consultation process developed the Jeddah recommendations on mitigation for the effects of the current pandemic influenza A (H1N1) virus during the 2009 Hajj, which is the last week of November ( 6 ). Here, we outline some of the realities associated with meeting those recommendations and the most recent plans to help mitigate the transmission burden.

Antiviral Treatment for Patients Hospitalized with 2009 Pandemic Influenza A (H1N1)

Abstract: With the 2009 H1N1 pandemic well under way, many clinicians are providing care to patients with influenza. Previously, although antiviral treatment was recommended,1,2 clinicians may not always have prescribed it to patients hospitalized with seasonal influenza, perhaps because of a perception that antiviral treatment had limited benefit. Controlled trials conducted among outpatients with uncomplicated seasonal influenza reported a reduction of approximately 1 day in the duration of illness and reduced severity when antiviral treatment was initiated within 48 hours of illness onset, as compared with placebo. However, evidence from observational studies supports the benefit of neuraminidase inhibitors (oseltamivir or . . .

Systematic Review: Safety and Efficacy of Extended-Duration Antiviral Chemoprophylaxis Against Pandemic and Seasonal Influenza

Abstract: events. Data Extraction: 2 reviewers independently assessed study quality and abstracted information from eligible studies. Data Synthesis: Of 1876 potentially relevant citations, 7 trials involving 7021 unique participants met inclusion criteria. Data were pooled by using random-effects models. Chemoprophylaxis with NAIs decreased the frequency of symptomatic influenza (relative risk [RR], 0.26 [95% CI, 0.18 to 0.37]; risk difference [RD], 3.9 percentage points [CI, 5.8 to 1.9 percentage points]) but not asymptomatic influenza (RR, 1.03 [CI, 0.81 to 1.30]; RD, 0.4 percentage point [CI, 1.6 to 0.9 percentage point]). Adverse effects were not increased overall among NAI recipients (RR, 1.01 [CI, 0.94 to 1.08]; RD, 0.1 percentage point [CI, 0.2 to 0.4 percentage point]), but nausea and vomiting were more common among those who took oseltamivir (RR, 1.48 [CI, 1.86 to 2.33]; RD, 1.7 percentage points [CI, 0.6 to 2.9 percentage points]). Prevention of influenza did not statistically significantly differ between zanamivir and oseltamivir. Limitations: All trials were industry-sponsored. No study was powered to detect rare adverse events, and none included diverse racial groups, children, immunocompromised patients, or individuals who received live attenuated influenza virus vaccine. Conclusion: Extended-duration zanamivir and oseltamivir chemoprophylaxis seems to be highly efficacious for preventing symptomatic influenza among immunocompetent white and Japanese adults. Extended-duration oseltamivir is associated with increased nausea and vomiting. Safety and efficacy in several subpopulations that might receive extended-duration influenza chemoprophylaxis are unknown.

Avian influenza virus A (H5N1), detected through routine surveillance, in child, Bangladesh.

Abstract: We identified avian influenza virus A (H5N1) infection in a child in Bangladesh in 2008 by routine influenza surveillance. The virus was of the same clade and phylogenetic subgroup as that circulating among poultry during the period. This case illustrates the value of routine surveillance for detection of novel influenza virus.

Seroprevalence of Antibodies to Avian Influenza Virus A (H5N1) among Residents of Villages with Human Cases, Thailand, 2005

Abstract: In 2005, we assessed the seroprevalence of neutralizing antibodies to avian influenza virus A (H5N1) among 901 residents of 4 villages in Thailand where at least 1 confirmed human case of influenza (H5N1) had occurred during 2004. Although 68.1% of survey participants (median age 40 years) were exposed to backyard poultry and 25.7% were exposed to sick or dead chickens, all participants were seronegative for influenza virus (H5N1).

What is the optimal therapy for patients with H5N1 influenza

Abstract: Background to the debate In a 2007 article in PLoS Medicine [10], Holger J. Schunemann and colleagues described a new process used by the World Health Organization for rapidly developing clinical management guidelines in emergency situations. These situations include outbreaks of emerging infectious diseases. The authors discussed how they developed such a “rapid advice” guideline for the pharmacological management of avian influenza A (H5N1) virus infection. The guideline recommends giving the antiviral drug oseltamivir at a dose of 75 mg twice daily for five days. In this Debate, Nicholas White argues that such dosing is inadequate, Robert Webster and Elena Govorkova say that combination antiviral therapy should be used, and Tim Uyeki reminds us that clinical care of patients with H5N1 entails much more than antiviral treatment. These issues may also apply to therapy of patients hospitalized with severe disease due to novel swine-origin influenza A (H1N1) virus infection.

Genetic analysis of avian influenza A viruses isolated from domestic waterfowl in live-bird markets of Hanoi, Vietnam, preceding fatal H5N1 human infections in 2004.

Abstract: The first known cases of human infection with highly pathogenic avian influenza (HPAI) H5N1 viruses in Vietnam occurred in late 2003 However, HPAI H5N1 and low-pathogenic avian influenza (LPAI) H5N2 and H9N3 viruses were isolated from domestic waterfowl during live-bird market (LBM) surveillance in Vietnam in 2001 and 2003 To understand the possible role of these early viruses in the genesis of H5N1 strains infecting people, we performed sequencing and molecular characterization Phylogenetic analysis revealed that the hemagglutinin (HA) genes of two geese HPAI H5N1 strains belonged to clade 3, and their surface glycoprotein and replication complex genes were most closely related (985-997% homologous) to A/duck/Guangxi/22/01 (H5N1) virus, detected contemporarily in southern China, whilst the M and NS genes were derived from an A/duck/Hong Kong/29861/00 (H5N1)-like virus The H5 HA gene of the duck HPAI H5N1 strain belonged to clade 5 and acquired a gene constellation from A/quail/Shantou/3846/02 (H5N1), A/teal/China/29781/02 (H5N1) and A/partridge/Shantou/2286/03 (H5N1)-like viruses The phylogenetic analysis further indicated that all eight gene segments of goose and duck HPAI H5N1 and LPAI H5N2 viruses were distinct from those of H5N1 clade-1 viruses known to have caused fatal human infections in Vietnam since late 2003 The duck H9N3 isolates derived genes from aquatic-bird influenza viruses, and their H9 HA belonged to the Korean lineage The PB2 gene of A/duck/Vietnam/340/01 (H9N3) virus had lysine at position 627 Based on the molecular characterization of specific amino acid residues in the surface and relevant internal protein-coding genes, the Vietnamese H5N1 and H9N3 virus isolates indicated specificity to avian cell surface receptor and susceptibility for currently licensed anti-influenza A virus chemotherapeutics Our findings suggest that the H5N1 and H5N2 viruses that circulated among geese and ducks in LBMs in Hanoi, Vietnam, during 2001 and 2003 were not the immediate ancestors of the clade-1 viruses associated with fatal human infections in Vietnam The clade-1 HPAI H5N1 viruses were independently introduced into Vietnam

Diagnostic testing for 2009 pandemic influenza A (H1N1) virus infection in hospitalized patients.

Abstract: Establishing a diagnosis of 2009 pandemic influenza A (H1N1) virus infection in hospitalized patients can be challenging, especially in patients presenting late in their clinical course. Although real-time reverse-transcriptase polymerase chain reaction (RT-PCR) is the most sensitive testing method to detect 2009 H1N1 virus in respiratory specimens,1 results are not accessible right away. Influenza antigen–detection tests produce quick results, but reported sensitivities of rapid influenza diagnostic tests (RIDTs) to detect 2009 H1N1 virus infection in upper respiratory specimens as compared with real-time RT-PCR range from 10 to 70%; therefore, false negative RIDT results are common2 and also occur with direct . . .