Background Pandemic influenza H1N1/09 emerged in April 2009 and spread widely in Australia and New Zealand. Although an unprecedented number of cases required intensive care, comparative community-based studies with seasonal influenza strains have not shown any significant differences in clinical symptoms or severity. Methods The authors performed active surveillance on confirmed influenza-rel...

UNLABELLED We have previously shown that 11 patients became naturally coinfected with seasonal H1N1 (A/H1N1) and pandemic H1N1 (pdm/H1N1) during the Southern hemisphere winter of 2009 in New Zealand. Reassortment of influenza A viruses is readily observed during coinfection of host animals and in vitro; however, reports of reassortment occurring naturally in humans are rare. Using clinical spec...

BACKGROUND Influenza A viruses are medically important viral pathogens that cause significant mortality and morbidity throughout the world. The recent emergence of a novel human influenza A virus (H1N1) poses a serious health threat. Molecular tests for rapid detection of this virus are urgently needed. METHODS We developed a conventional 1-step RT-PCR assay and a 1-step quantitative real-tim...

OBJECTIVE We sought to understand pandemic 2009 influenza A (H1N1) vaccine acceptance in a minority community including correlates of vaccine hesitancy and refusal. We identified intervention points to increase H1N1 vaccine coverage. PATIENTS AND METHODS Minority parents and caregivers of children ≤ 18 years participated in a cross-sectional survey. Statistical analyses included bivariate cor...

Background. During the 2009 spring epidemic outbreak in Mexico, an important research and policy question faced was related to the differences in clinical profile and population characteristics of those affected by the new H1N1 virus compared with the seasonal virus. Methods and Findings. Data from clinical files from all influenza A deaths in Mexico between April 10 and July 13, 2009 were anal...

Two influenza A subtypes (H1N1 and H3N2) co-circulate pose a serious disease burden globally. It is unclear about the extent of cross-protection between these two as well impact on dynamics. Based an evolution-driven mathematical transmission model, interaction H1N1 H3N2 was explored based monthly incidence data in USA from years 2012 to 2019. The results showed that significant exists. Besides...

The His274→Tyr (H274Y) oseltamivir (Tamiflu) resistance mutation causes a substantial decrease in the total levels of surface-expressed neuraminidase protein and activity in early isolates of human seasonal H1N1 influenza, and in the swine-origin pandemic H1N1. In seasonal H1N1, H274Y only became widespread after the occurrence of secondary mutations that counteracted this decrease. H274Y is cu...

BACKGROUND An age bias toward children and young adults has been reported for infection and hospitalizations with pandemic H1N1 influenza (A[H1N1]pdm) in the 2009 and 2010 influenza seasons in the Southern and Northern Hemispheres. Serological analysis of prepandemic samples has shown a higher incidence of cross-reactive antibodies to A(H1N1)pdm virus in older populations; conserved T cell epit...

BACKGROUND Presentation of pandemic H1N1 influenza (H1N1) is widely evolving as it continues to involve different geographic locations and populations. This study was conducted to improve the precision of clinical diagnosis of H1N1 (2009) influenza infection in an outpatient setting. MATERIALS AND METHODS A prospective cross-sectional study was conducted among adult patients (age >15 years) w...

BACKGROUND The main objective of this study was to describe the patients who were hospitalised at Oslo University Hospital Aker during the first wave of pandemic Influenza A (H1N1) in Norway. METHODS Clinical data on all patients hospitalised with influenza-like illness from July to the end of November 2009 were collected prospectively. Patients with confirmed H1N1 Influenza A were compared t...