The remarkable infectivity and virulence of the 1918 influenza virus resulted in an unprecedented pandemic, raising the question of whether it is possible to develop protective immunity to this virus and whether immune evasion may have contributed to its spread. Here, we report that the highly lethal 1918 virus is susceptible to immune protection by a preventive vaccine, and we define its mecha...

In 1918 an influenza pandemic killed 40 million people. It is now possible to study the genetic features of the 1918 virus. Such analyses will try to answer questions about the origin and the unusual virulence of this pandemic virus.

The 1918 influenza pandemic caused more than 40 million deaths and likely resulted from the introduction and adaptation of a novel avian-like virus. Influenza A virus hemagglutinins are important in host switching and virulence. Avian-adapted influenza virus hemagglutinins bind sialic acid receptors linked via alpha2-3 glycosidic bonds, while human-adapted hemagglutinins bind alpha2-6 receptors...

The Spanish influenza pandemic in the years 1918-1920 was the largest and most tragic pandemic of infectious disease in human history. Deciphering the structure of the virus (including the determination of complete genome sequence) of this pandemic and the phylogenetic analysis and explanation of its virulence became possible thanks to molecular genetic analysis of the virus isolated from the f...

BACKGROUND Although the mortality burden of the devastating 1918 influenza pandemic has been carefully quantified in the United States, Japan, and European countries, little is known about the pandemic experience elsewhere. Here, we compiled extensive archival records to quantify the pandemic mortality patterns in 2 Mexican cities, Mexico City and Toluca. METHODS We applied seasonal excess mo...

UNLABELLED Zoonotic avian influenza virus infections may lead to epidemics or pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its H1 hemagglutinin was identified as a key mammalian virulence factor. A chimeric 1918 virus expressing a contemporary avian H1 hemagglutinin, however, displayed murine pathogenicity indistinguishable from that of the 1918 vir...

To the editor: The 1918 Spanish flu pandemic is estimated to have infected one-third of the world’s population and caused mortality ranging from 20 millions to 100 millions. The geographical origin of the 1918 influenza remains debatable. During an approximately 12-month period in 1918– 1919, the pandemic spread more or less simultaneously in Asia, Europe, and North America in three waves. In t...

The enormous toll on human life during the 1918-1919 Spanish influenza pandemic is a constant reminder of the potential lethality of influenza viruses. With the declaration by the World Health Organization of a new H1N1 influenza virus pandemic, and with continued human cases of highly pathogenic H5N1 avian influenza virus infection, a better understanding of the host response to highly pathoge...

To quantify age-specific excess-mortality rates and transmissibility patterns for the 1918-20 influenza pandemic in Boyacá, Colombia, we reviewed archival mortality records. We identified a severe pandemic wave during October 1918-January1919 associated with 40 excess deaths per 10,000 population. The age profile for excess deaths was W shaped; highest mortality rates were among infants (<5 y o...

The proapoptotic PB1-F2 protein of influenza A viruses has been shown to contribute to pathogenesis in the mouse model. Expression of full-length PB1-F2 increases the pathogenesis of the influenza A virus, causing weight loss, slower viral clearance, and increased viral titers in the lungs. After comparing viruses from the Hong Kong 1997 H5N1 outbreak, one amino acid change (N66S) was found in ...