1918 influenza virus: 100 years on, are we prepared against the next influenza pandemic?
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ABSTRACT:
SUBMITTER: Medina RA
PROVIDER: S-EPMC8628252 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The 1918 influenza A virus caused the most devastating pandemic, killing approximately 50 million people worldwide. Immunization with 1918-like and classical swine H1N1 virus vaccines results in cross-protective antibodies against the 2009 H1N1 pandemic influenza, indicating antigenic similarities among these viruses. In this study, we demonstrate that vaccination with the 2009 pandemic H1N1 vaccine elicits 1918 virus cross-protective antibodies in mice and humans, and that vaccination or passive transfer of human-positive sera reduced morbidity and conferred full protection from lethal challenge with the 1918 virus in mice. The spread of the 2009 H1N1 influenza virus in the population worldwide, in addition to the large number of individuals already vaccinated, suggests that a large proportion of the population now have cross-protective antibodies against the 1918 virus, greatly alleviating concerns and fears regarding the accidental exposure/release of the 1918 virus from the laboratory and the use of the virus as a bioterrorist agent.
| S-EPMC2964451 | biostudies-other
Project description:The nucleoprotein (NP) gene of the 1918 pandemic influenza A virus has been amplified and sequenced from archival material. The NP gene is known to be involved in many aspects of viral function and to interact with host proteins, thereby playing a role in host specificity. The 1918 NP amino acid sequence differs at only six amino acids from avian consensus sequences, consistent with reassortment from an avian source shortly before 1918. However, the nucleotide sequence of the 1918 NP gene has more than 170 differences from avian strain consensus sequences, suggesting substantial evolutionary distance from known avian strain sequences. Both the gene and protein sequences of the 1918 NP fall within the mammalian clade upon phylogenetic analysis. The evolutionary distance of the 1918 NP sequences from avian and mammalian strain sequences is examined, using several different parameters. The results suggest that the 1918 strain did not retain the previously circulating human NP. Nor is it likely to have obtained its NP by reassortment with an avian strain similar to those now characterized. The results are consistent with the existence of a currently unknown host for influenza, with an NP similar to current avian strain NPs at the amino acid level but with many synonymous nucleotide differences, suggesting evolutionary isolation from the currently characterized avian influenza virus gene pool.
| S-EPMC525067 | biostudies-literature
Project description:The 1918 influenza pandemic killed 20-40 million people worldwide, and is seen as a worst-case scenario for pandemic planning. Like other pandemic influenza strains, the 1918 A/H1N1 strain spread extremely rapidly. A measure of transmissibility and of the stringency of control measures required to stop an epidemic is the reproductive number, which is the number of secondary cases produced by each primary case. Here we obtained an estimate of the reproductive number for 1918 influenza by fitting a deterministic SEIR (susceptible-exposed-infectious-recovered) model to pneumonia and influenza death epidemic curves from 45 US cities: the median value is less than three. The estimated proportion of the population with A/H1N1 immunity before September 1918 implies a median basic reproductive number of less than four. These results strongly suggest that the reproductive number for 1918 pandemic influenza is not large relative to many other infectious diseases. In theory, a similar novel influenza subtype could be controlled. But because influenza is frequently transmitted before a specific diagnosis is possible and there is a dearth of global antiviral and vaccine stores, aggressive transmission reducing measures will probably be required.
| S-EPMC7095078 | biostudies-literature
Project description:The 1918 influenza pandemic was the most significant pandemic recorded in human history. Worldwide, an estimated half billion persons were infected and 20 to 100 million people died in three waves during 1918 to 1919. Yet the impact of this pandemic has been poorly documented in many countries especially those in Africa. We used colonial-era records to describe the impact of 1918 influenza pandemic in the Coast Province of Kenya. We gathered quantitative data on facility use and all-cause mortality from 1912 to 1925, and pandemic-specific data from active reporting from September 1918 to March 1919. We also extracted quotes from correspondence to complement the quantitative data and describe the societal impact of the pandemic. We found that crude mortality rates and healthcare utilization increased six- and three-fold, respectively, in 1918, and estimated a pandemic mortality rate of 25.3 deaths/1000 people/year. Impact to society and the health care system was dramatic as evidenced by correspondence. In conclusion, the 1918 pandemic profoundly affected Coastal Kenya. Preparation for the next pandemic requires continued improvement in surveillance, education about influenza vaccines, and efforts to prevent, detect and respond to novel influenza outbreaks.
| S-EPMC6631354 | biostudies-other
Project description:The source, timing, and geographical origin of the 1918-1920 pandemic influenza A virus have remained tenaciously obscure for nearly a century, as have the reasons for its unusual severity among young adults. Here, we reconstruct the origins of the pandemic virus and the classic swine influenza and (postpandemic) seasonal H1N1 lineages using a host-specific molecular clock approach that is demonstrably more accurate than previous methods. Our results suggest that the 1918 pandemic virus originated shortly before 1918 when a human H1 virus, which we infer emerged before ?1907, acquired avian N1 neuraminidase and internal protein genes. We find that the resulting pandemic virus jumped directly to swine but was likely displaced in humans by ?1922 by a reassortant with an antigenically distinct H1 HA. Hence, although the swine lineage was a direct descendent of the pandemic virus, the post-1918 seasonal H1N1 lineage evidently was not, at least for HA. These findings help resolve several seemingly disparate observations from 20th century influenza epidemiology, seroarcheology, and immunology. The phylogenetic results, combined with these other lines of evidence, suggest that the high mortality in 1918 among adults aged ?20 to ?40 y may have been due primarily to their childhood exposure to a doubly heterosubtypic putative H3N8 virus, which we estimate circulated from ?1889-1900. All other age groups (except immunologically naive infants) were likely partially protected by childhood exposure to N1 and/or H1-related antigens. Similar processes may underlie age-specific mortality differences between seasonal H1N1 vs. H3N2 and human H5N1 vs. H7N9 infections.
| S-EPMC4050607 | biostudies-literature
Project description:The purpose of this experiment was to understand the pathogenic role of individual 1918 genes on the host response to the 1918 pandemic influenza virus. We examined reassortant avian viruses nearly identical to the pandemic 1918 virus (1918-like avian virus) carrying either the 1918 HA or PB2 gene. Both genes enhanced 1918-like avian virus replication, but only the mammalian host adaptation of the 1918-like avian virus through reassortment of the 1918 PB2 led to increased lethality in mice. We demonstrate that 1918 PB2 enhances immune and inflammatory responses concomitant with increased cellular infiltration in the lung. We also show that 1918 PB2 expression results in the repression of both canonical and non-canonical Wnt signaling pathways which are crucial for inflammation mediated lung regeneration and repair.
2015-12-31 | GSE70502 | GEO
Project description:BACKGROUND:Increasing our knowledge of past influenza pandemic patterns in different regions of the world is crucial to guide preparedness plans against future influenza pandemics. Here, we undertook extensive archival collection efforts from three representative cities of Peru-Lima in the central coast, Iquitos in the northeastern Amazon region, Ica in the southern coast-to characterize the temporal, age and geographic patterns of the 1918-1920 influenza pandemic in this country. MATERIALS AND METHODS:We analyzed historical documents describing the 1918-1920 influenza pandemic in Peru and retrieved individual mortality records from local provincial archives for quantitative analysis. We applied seasonal excess mortality models to daily and monthly respiratory mortality rates for 1917-1920 and quantified transmissibility estimates based on the daily growth rate in respiratory deaths. RESULTS:A total of 52,739 individual mortality records were inspected from local provincial archives. We found evidence for an initial mild pandemic wave during July-September 1918 in Lima, identified a synchronized severe pandemic wave of respiratory mortality in all three locations during November 1918-February 1919, and a severe pandemic wave during January 1920-March 1920 in Lima and July-October 1920 in Ica. There was no recrudescent pandemic wave in 1920 in Iquitos. Remarkably, Lima experienced the brunt of the 1918-1920 excess mortality impact during the 1920 recrudescent wave, with all age groups experiencing an increase in all cause excess mortality from 1918-1919 to 1920. Middle age groups experienced the highest excess mortality impact, relative to baseline levels, in the 1918-1919 and 1920 pandemic waves. Cumulative excess mortality rates for the 1918-1920 pandemic period were higher in Iquitos (2.9%) than Lima (1.6%). The mean reproduction number for Lima was estimated in the range 1.3-1.5. CONCLUSIONS:We identified synchronized pandemic waves of intense excess respiratory mortality during November 1918-February 1919 in Lima, Iquitos, Ica, followed by asynchronous recrudescent waves in 1920. Cumulative data from quantitative studies of the 1918 influenza pandemic in Latin American settings have confirmed the high mortality impact associated with this pandemic. Further historical studies in lesser studied regions of Latin America, Africa, and Asia are warranted for a full understanding of the global impact of the 1918 pandemic virus.
| S-EPMC3144394 | biostudies-literature
Project description:Influenza viruses are highly transmissible, both within and between host species. The severity of the disease they cause is highly variable, from the mild and inapparent through to the devastating and fatal. The unpredictability of epidemic and pandemic outbreaks is accompanied but the predictability of seasonal disease in wide areas of the Globe, providing an inexorable toll on human health and survival. Although there have been great improvements in understanding influenza viruses and the disease that they cause, our knowledge of the effects they have on the host and the ways that the host immune system responds continues to develop. This review highlights the importance of the mucosa in defence against infection and in understanding the pathogenesis of disease. Although vaccines have been available for many decades, they remain suboptimal in needing constant redesign and in only providing short-term protection. There are real prospects for improvement in treatment and prevention of influenza soon, based on deeper knowledge of how the virus transmits, replicates and triggers immune defences at the mucosal surface.
| S-EPMC7223327 | biostudies-literature
Project description:Wild birds harbor a large gene pool of influenza A viruses that have the potential to cause influenza pandemics. Foreseeing and understanding this potential is important for effective surveillance. Our phylogenetic and geographic analyses revealed the global prevalence of avian influenza virus genes whose proteins differ only a few amino acids from the 1918 pandemic influenza virus, suggesting that 1918-like pandemic viruses may emerge in the future. To assess this risk, we generated and characterized a virus composed of avian influenza viral segments with high homology to the 1918 virus. This virus exhibited pathogenicity in mice and ferrets higher than that in an authentic avian influenza virus. Further, acquisition of seven amino acid substitutions in the viral polymerases and the hemagglutinin surface glycoprotein conferred respiratory droplet transmission to the 1918-like avian virus in ferrets, demonstrating that contemporary avian influenza viruses with 1918 virus-like proteins may have pandemic potential.
| S-EPMC4205238 | biostudies-literature
Project description: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 mechanism of action. Immunization with plasmid expression vectors encoding hemagglutinin (HA) elicited potent CD4 and CD8 cellular responses as well as neutralizing antibodies. Antibody specificity and titer were defined by a microneutralization and a pseudotype assay that could assess antibody specificity without the need for high-level biocontainment. This pseudotype inhibition assay can define evolving serotypes of influenza viruses and facilitate the development of immune sera and neutralizing monoclonal antibodies that may help contain pandemic influenza. Notably, mice vaccinated with 1918 HA plasmid DNAs showed complete protection to lethal challenge. T cell depletion had no effect on immunity, but passive transfer of purified IgG from anti-H1(1918) immunized mice provided protective immunity for naïve mice challenged with infectious 1918 virus. Thus, humoral immunity directed at the viral HA can protect against the 1918 pandemic virus.
| S-EPMC1613227 | biostudies-literature