BACKGROUND Prior experience and the persisting threat of influenza pandemic indicate the need for global and local preparedness and public health response capacity. The pandemic of 2009 highlighted the importance of such planning and the value of prior efforts at all levels. Our review of the public health response to this pandemic in Pune, India, considers the challenges of integrating global ...

BACKGROUND The burden of the pandemic (H1N1) 2009 influenza might be underestimated if detection of the virus is mandated to diagnose infection. Using an alternate approach, we propose that a much higher pandemic burden was experienced in our institution. METHODOLOGY/PRINCIPAL FINDINGS Consecutive patients (n = 2588) presenting to our hospital with influenza like illness (ILI) or severe acute...

PURPOSE OF STUDY The demographics, clinical features and outcome of patients with pandemic influenza A (H1N1) 2009 infection were compared with a concurrent cohort of patients with seasonal influenza A infection. STUDY DESIGN The clinical and microbiological data of hospitalised adult patients admitted between 29 June and 28 October 2009, with pandemic A (H1N1) 2009 or seasonal influenza A in...

Pandemic influenza viruses cause significant mortality in humans. In the 20th century, 3 influenza viruses caused major pandemics: the 1918 H1N1 virus, the 1957 H2N2 virus, and the 1968 H3N2 virus. These pandemics were initiated by the introduction and successful adaptation of a novel hemagglutinin subtype to humans from an animal source, resulting in antigenic shift. Despite global concern reg...

BACKGROUND An H1N1 subtype of swine origin caused the first influenza pandemic in this century. This pandemic strain was a reassortant of avian, swine, and human influenza viruses. Many diagnostic laboratories were overwhelmed by the testing demands related to this pandemic. Nevertheless, there remains the threat of other animal influenza viruses, such as highly pathogenic H5N1. As a part of pa...

The World Health Organization's declaration of an imminent swine-origin influenza A pandemic in April 2009 triggered the global launch of national pandemic preparedness plans. An integral component of pandemic preparedness in many countries was the targeted use of antiviral therapy for containment, disease mitigation, and treatment. The 2009 pandemic marked the first pandemic during which influ...

Pandemic influenza remains a serious public health threat and the processes involved in the evolutionary emergence of pandemic influenza strains remain incompletely understood. Here, we develop a stochastic model for the evolutionary emergence of pandemic influenza, and use it to address three main questions. (i) What is the minimum annual number of avian influenza virus infections required in ...

Epidemiologic observations that have been made in the context of the current pandemic influenza virus include a stable virulence phenotype and a lack of propensity to reassort with seasonal strains. In an attempt to determine whether either of these observations could change in the future, we coinfected differentiated human airway cells with seasonal oseltamivir-resistant A/New Jersey/15/07 and...

The current pandemic threat can be best understood within an ecological framework that takes account of the history of past pandemics caused by influenza A, the relationships between pandemic and seasonal spread of influenza viruses, and the importance of immunity and behavioural responses in human populations. Isolated populations without recent exposure to seasonal influenza seem more suscept...

Understanding the origin of infectious diseases provides scientifically based rationales for implementing public health measures that may help to avoid or mitigate future epidemics. The recent ancestors of a pandemic virus provide invaluable information about the set of minimal genomic alterations that transformed a zoonotic agent into a full human pandemic. Since the first confirmed cases of t...