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 (PaO(2)/FiO(2) ≤ 250), bilateral lung infiltration, and old age (≥ 65 yr) were independent risk factors for severe cases (all P < 0.001). The area under the ROC curve (0.834 [95% CI, 0.778-0.890]) of the number of risk factors were not significantly different with that of APACHE II score (0.840 [95% CI, 0.790-0.891]) (P = 0.496). The presence of ≥ 2 risk factors had a higher sensitivity, specificity, positive predictive value and negative predictive value than an APACHE II score of ≥ 13. As a prediction rule, the presence of ≥ 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.

Kinetics, Longevity, and Cross-Reactivity of Antineuraminidase Antibody after Natural Infection with Influenza A Viruses.

The kinetics, longevity, and breadth of antibodies to influenza virus neuraminidase (NA) in archival, sequential serum/plasma samples from influenza A virus (IAV) H5N1 infection survivors and from patients infected with the 2009 pandemic IAV (H1N1) virus were determined using an enzyme-linked lectin-based assay. The reverse-genetics-derived H4N1 viruses harboring a hemagglutinin (HA) segment from A/duck/Shan Tou/461/2000 (H4N9) and an NA segment derived from either IAV H5N1 clade 1, IAV H5N1 clade 2.3.4, the 2009 pandemic IAV (H1N1) (H1N1pdm), or A/Puerto Rico/8/1934 (H1N1) virus were used as the test antigens. These serum/plasma samples were also investigated by microneutralization (MN) and/or hemagglutination inhibition (HI) assays. Neuraminidase-inhibiting (NI) antibodies against N1 NA of both homologous and heterologous viruses were observed in H5N1 survivors and H1N1pdm patients. H5N1 survivors who were never exposed to H1N1pdm virus developed NI antibodies to H1N1pdm NA. Seroconversion of NI antibodies was observed in 65% of the H1N1pdm patients at day 7 after disease onset, but an increase in titer was not observed in serum samples obtained late in infection. On the other hand, an increase in seroconversion rate with the HI assay was observed in the follow-up series of sera obtained on days 7, 14, 28, and 90 after infection. The study also showed that NI antibodies are broadly reactive, while MN and HI antibodies are more strain specific.

Adverse events following pandemic influenza A (H1N1) 2009 monovalent and seasonal influenza vaccinations during the 2009-2010 season in the active component U.S. military and civilians aged 17-44years reported to the Vaccine Adverse Event Reporting System.

BACKGROUND: No comparative review of Vaccine Adverse Event Reporting System (VAERS) submissions following pandemic influenza A (H1N1) 2009 and seasonal influenza vaccinations during the pandemic season among U.S. military personnel has been published. METHODS: We compared military vs. civilian adverse event reporting rates. Adverse events (AEs) following vaccination were identified from VAERS for adults aged 17-44years after pandemic (monovalent influenza [MIV], and seasonal (trivalent inactivated influenza [IIV3], live attenuated influenza [LAIV3]) vaccines. Military vaccination coverage was provided by the Department of Defense's Defense Medical Surveillance System. Civilian vaccination coverage was estimated using data from the National 2009 H1N1 Flu Survey and the Behavioral Risk Factor Surveillance System survey. RESULTS: Vaccination coverage was more than four times higher for MIV and more than twenty times higher for LAIV3 in the military than in the civilian population. The reporting rate of serious AE reports following MIV in service personnel (1.19 per 100,000) was about half that reported by the civilian population (2.45 per 100,000). Conversely, the rate of serious AE reports following LAIV3 among service personnel (1.32 per 100,000) was more than twice that of the civilian population. Although fewer military AEs following MIV were reported overall, the rate of Guillain-Barré Syndrome (GBS) (4.01 per million) was four times greater than that in the civilian population. (1.04 per million). CONCLUSIONS: Despite higher vaccination coverage in service personnel, the rate of serious AEs following MIV was about half that in civilians. The rate of GBS reported following MIV was higher in the military.

Differential proteomic analysis of respiratory samples from patients suffering from influenza.

The exact molecular pathways involved in the pathogenesis of influenza are yet unclear. In the present study we investigated the upper respiratory proteome in influenza patients. 200 nasal and throat swab samples were collected from patients suffering from acute respiratory illness. These samples were confirmed for influenza pandemic A/H1N1/2009 and influenza type B using qRT-PCR. 10 similar swabs were collected from healthy individuals and were used as controls. Proteins were extracted from the cell pellets and were subjected to 2-D gel electrophoresis. The differentially expressed proteins were identified using MALDI-TOF. Identified proteins were classified into different functional groups based on functions reported in the databases. 25 % of these proteins were involved in cytoskeletal formation, whereas 14 % were involved in signal transduction. Proteins involved in anti-viral responses, Ca-signaling, transport, and tumor suppression constituted 10 % each, where as 5 % of proteins each belong to Nicotinic acetylcholine receptor, Protein Synthesis and anti-bacterial proteins. 10 % of the proteins have not been described previously. This is the first report on respiratory proteome profile in Influenza patients. The study emphasizes the role of such profiling studies using multiple platforms for bio-marker discoveries, especially non-invasive diagnostic marker in Influenza and other infectious diseases.

A/H1N1 vaccine intentions in college students: an application of the theory of planned behavior.

OBJECTIVE: To test the applicability of the Theory of Planned Behavior (TPB) in college students who have not previously received the A/H1N1 vaccine. PARTICIPANTS: Undergraduate communication students at a metropolitan southern university. METHODS: In January-March 2010, students from voluntarily participating communication classes completed a hardcopy survey assessing TPB and clinically significant constructs. Hierarchical regression equations predicted variance in vaccine intentions of students who had not received a flu shot (N=198; 70% Caucasian). RESULTS: The TPB model explained 51.7% (p<.001) of variance in vaccine intentions. Controlling for side effects, self-efficacy and perceived comparative susceptibility predicted intentions when entered in the first block, whereas attitudes, subjective norms, and perceived behavioral control significantly contribute when entered in the second block. CONCLUSIONS: For students who have not previously received a flu vaccine, vaccine communication should utilize self-efficacy and perceived comparative susceptibility to employ the TPB to promote vaccine intentions.

Trends of influenza infection in Suriname.

The trends of influenza infection in Suriname were assessed from February 2010 through February 2011. Testing of 393 patients with symptoms of acute respiratory infection (ARI) revealed 15.3% Influenza B and 18.6% could be identified as influenza A positive, consisting of 56% influenza A(H1N1)pdm09 and 44% seasonal A(H3N2). Influenza infection occurred throughout the year, and all three influenza types affected young children as the primary population. The annual incidence of A(H1N1)pdm09 was 6.88 per 100,000 inhabitants [CI] 4.87-9.45. The spread of influenza could neither be linked to tourist flow from the Netherlands nor to contact rates related to school schedules.

Oseltamivir-resistant influenza A pandemic (H1N1) 2009 virus in Northern Greece.

Resistance to oseltamivir was observed to influenza A pandemic (H1N1) 2009 virus strains, isolated from two patients in North Greece. Investigations showed resistant viruses with the neuraminidase (NA) 275Y genotypes. Pandemic A (H1N1) 2009 virus should be closely monitored for emergence of resistant variants.

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.

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.

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.

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.