scholarly journals Cluster analysis of the origins of the new influenza A(H1N1) virus

2009 ◽  
Vol 14 (21) ◽  
Author(s):  
A Solovyov ◽  
G Palacios ◽  
T Briese ◽  
W I Lipkin ◽  
R Rabadan

In March and April 2009, a new strain of influenza A(H1N1) virus has been isolated in Mexico and the United States. Since the initial reports more than 10,000 cases have been reported to the World Health Organization, all around the world. Several hundred isolates have already been sequenced and deposited in public databases. We have studied the genetics of the new strain and identified its closest relatives through a cluster analysis approach. We show that the new virus combines genetic information related to different swine influenza viruses. Segments PB2, PB1, PA, HA, NP and NS are related to swine H1N2 and H3N2 influenza viruses isolated in North America. Segments NA and M are related to swine influenza viruses isolated in Eurasia.

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1145
Author(s):  
Hakimeh Baghaei Daemi ◽  
Muhammad Fakhar-e-Alam Kulyar ◽  
Xinlin He ◽  
Chengfei Li ◽  
Morteza Karimpour ◽  
...  

Influenza is a highly known contagious viral infection that has been responsible for the death of many people in history with pandemics. These pandemics have been occurring every 10 to 30 years in the last century. The most recent global pandemic prior to COVID-19 was the 2009 influenza A (H1N1) pandemic. A decade ago, the H1N1 virus caused 12,500 deaths in just 19 months globally. Now, again, the world has been challenged with another pandemic. Since December 2019, the first case of a novel coronavirus (COVID-19) infection was detected in Wuhan. This infection has risen rapidly throughout the world; even the World Health Organization (WHO) announced COVID-19 as a worldwide emergency to ensure human health and public safety. This review article aims to discuss important issues relating to COVID-19, including clinical, epidemiological, and pathological features of COVID-19 and recent progress in diagnosis and treatment approaches for the COVID-19 infection. We also highlight key similarities and differences between COVID-19 and influenza A to ensure the theoretical and practical details of COVID-19.


2012 ◽  
Vol 21 (6) ◽  
pp. 441-450 ◽  
Author(s):  
Zvonimir Majić ◽  
Irena Jukić ◽  
Stanislav Pavlin

In April 2009, the WHO, (World Health Organization) evaluated the available data on the swine influenza A (H1N1), confirmed the outbreak and declared decision on raising the pandemic phase from five to six. IATA, (International Air Transport Association) invited the airlines to support WHO’s reference laboratories around the world in handling specimens should the outbreak expand further. The specimens shall be transported according to the regulations stipulated for acceptance and transportation of dangerous goods by air. The paper analyses the current infrastructural situation at the airports in Croatia, predispositions related to the trained staff and coordination procedures with the relevant institutions. The implementation of activities complying with the international regulations are suggested in order to conduct measures fighting the pandemic in Croatia. KEY WORDS: pandemic outbreak, regulation, recommendation, specimen, responsibilities, transportation and logistic for biological substances


2009 ◽  
Vol 14 (20) ◽  
Author(s):  
A Melidou ◽  
G Gioula ◽  
M Exindari ◽  
D Chatzidimitriou ◽  
E Diza-Mataftsi

Influenza viruses continue to threaten the world with a new pandemic. While currently attention is focused on the newly emerged A(H1N1) virus, the avian influenza A(H5N1) virus is still a cause of concern. Extended research is focused on the genetic evolution of the viruses, as well as their susceptibility to available antiviral drugs. One of the major priorities of the World Health Organization is to develop candidate vaccines, four of which are already licensed for use in the European Union. Since the last influenza pandemic in 1968, our knowledge of the influenza virus and its biology has greatly increased, revealing new avenues in the research for antiviral strategies and the development of effective vaccines.


2009 ◽  
Vol 21 (6) ◽  
pp. 987-989 ◽  
Author(s):  
Sandra S. Chan ◽  
Linda C. W. Lam ◽  
Helen F. K. Chiu

The emergence of the novel swine-origin influenza A (H1N1) virus in humans has aroused great concern among medical professionals about the possible evolution of a full-blown influenza pandemic, one on the scale of the “Spanish” influenza pandemic of 1918–19 (Belshe, 2009). It has been speculated that the return of a pandemic virus equivalent in pathogenicity to the virus of 1918 would likely kill more than 100 million people worldwide, including a large number of economically active young people (Taubenberger and Morens, 2006). Health administrations worldwide have stepped up reporting and surveillance of the deaths and illnesses associated with H1N1, and most countries have national strategies to fight the outbreak, though skeptics doubt how such plans could be operationalized, especially in developing countries (Coker, 2009). As of 6 July 2009, the cumulative total of H1N1 cases exceeds 90,000 in over 100 countries, with over 400 deaths directly related to the infection (World Health Organization, 2009a). Optimists might believe this pandemic is not going to match the scale of the historical 1918 pandemic given the relatively low fatality rate observed thus far. However, the World Health Organization has cautioned that we have just entered Phase 6 of the pandemic – i.e. we are in the early days of the 2009 flu pandemic (Chan, 2009). The course of the pandemic is thus unpredictable at this stage but it is evident that international multilateral plans and agreements have enabled much greater coordination of communication and action than ever before. The guidance behind these multilateral international actions, rooted in the World Health Organization's International Health Regulations (IHR) 2005, only came into being five years ago in response to the threat of emerging infectious diseases and particularly by the events related to the emergence of Severe Acute Respiratory Syndrome (SARS) (Katz, 2009). The morbidity and mortality directly resulting from this novel influenza A H1N1 outbreak are in the center of the world media's spotlight, but the potential impact of the pandemic on global mental health has not yet received the attention it deserves.


2014 ◽  
Vol 63 (12) ◽  
pp. 1626-1637 ◽  
Author(s):  
Mara L. Russo ◽  
Andrea V. Pontoriero ◽  
Estefania Benedetti ◽  
Andrea Czech ◽  
Martin Avaro ◽  
...  

This study was conducted as part of the Argentinean Influenza and other Respiratory Viruses Surveillance Network, in the context of the Global Influenza Surveillance carried out by the World Health Organization (WHO). The objective was to study the activity and the antigenic and genomic characteristics of circulating viruses for three consecutive seasons (2010, 2011 and 2012) in order to investigate the emergence of influenza viral variants. During the study period, influenza virus circulation was detected from January to December. Influenza A and B, and all current subtypes of human influenza viruses, were present each year. Throughout the 2010 post-pandemic season, influenza A(H1N1)pdm09, unexpectedly, almost disappeared. The haemagglutinin (HA) of the A(H1N1)pdm09 viruses studied were segregated in a different genetic group to those identified during the 2009 pandemic, although they were still antigenically closely related to the vaccine strain A/California/07/2009. Influenza A(H3N2) viruses were the predominant strains circulating during the 2011 season, accounting for nearly 76 % of influenza viruses identified. That year, all HA sequences of the A(H3N2) viruses tested fell into the A/Victoria/208/2009 genetic clade, but remained antigenically related to A/Perth/16/2009 (reference vaccine recommended for this three-year period). A(H3N2) viruses isolated in 2012 were antigenically closely related to A/Victoria/361/2011, recommended by the WHO as the H3 component for the 2013 Southern Hemisphere formulation. B viruses belonging to the B/Victoria lineage circulated in 2010. A mixed circulation of viral variants of both B/Victoria and B/Yamagata lineages was detected in 2012, with the former being predominant. A(H1N1)pdm09 viruses remained antigenically closely related to the vaccine virus A/California/7/2009; A(H3N2) viruses continually evolved into new antigenic clusters and both B lineages, B/Victoria/2/87-like and B/Yamagata/16/88-like viruses, were observed during the study period. The virological surveillance showed that the majority of the circulating strains during the study period were antigenically related to the corresponding Southern Hemisphere vaccine strains except for the 2012 A(H3N2) viruses.


2014 ◽  
Vol 9 (5) ◽  
pp. 842-847
Author(s):  
Reiko Saito ◽  
◽  
Yadanar Kyaw ◽  
Yi Yi Myint ◽  
Clyde Dapat ◽  
...  

The epidemiological study of influenza in Southeast Asia is limited. We surveyed influenza in Myanmar from 2007 to 2013. Nasopharyngeal swabs were collected from patients in the two cities of Yangon and Nay Pyi Taw. Samples were screened using rapid influenza diagnostic kits and identified by virus isolation. Isolates were characterized by cyclingprobe-based real-time PCR, drug susceptibility assay, and sequencing. Samples collected numbered 5,173, from which 1,686 influenza viruses were isolated during the seven-year study period. Of these, 187 strains were of seasonal influenza A(H1N1), 274 of influenza A(H1N1)pdm09, 791 of influenza A(H3N2), and 434 of influenza B. Interestingly, two zanamivir and amantadine-resistant strains each were detected in 2007 and 2008. These rare dual-resistant strains had a Q136K mutation in the NA protein and S31N substitution in the M2 protein. Our collaboration raised the influenza surveillance laboratory capacity in Myanmar and led Yangon’s National Health Laboratory – one of the nation’s leading research institutes – to being designated a National Influenza Center by the World Health Organization.


2009 ◽  
Vol 20 (4) ◽  
pp. 334-341
Author(s):  
Nancy Blake ◽  
Kathleen Stevenson ◽  
Dawn England

In March 2009, a child in Mexico was infected with novel influenza A (H1N1), otherwise known as swine flu. Otherwise healthy children in that small town came down with it shortly after, as well as others from other countries who had visited Mexico or been visited by someone from Mexico, as was the case in the United States. The Centers for Disease Control and Prevention confirmed the first 2 cases in April 2009 and has been working together with local health departments to do syndromic surveillance. In June 2009, the World Health Organization raised the pandemic alert to level 6. Pandemic H1N1, as it is now called, has infected otherwise healthy people younger than 25 years. Most patients present with fever, sore throat, and cough. Transmission is via droplets; therefore, appropriate precautions should be taken. Antiviral care is usually recommended for those who are hospitalized, and the virus has been found to be susceptible to oseltamivir (Tamiflu) and zanamivir (Relenza). Hospitals should work with local health departments for confirmation of the flu and implement pandemic plans as necessary.


2010 ◽  
Vol 84 (9) ◽  
pp. 4194-4203 ◽  
Author(s):  
Jessica A. Belser ◽  
Debra A. Wadford ◽  
Claudia Pappas ◽  
Kortney M. Gustin ◽  
Taronna R. Maines ◽  
...  

ABSTRACT The pandemic H1N1 virus of 2009 (2009 H1N1) continues to cause illness worldwide, primarily in younger age groups. To better understand the pathogenesis of these viruses in mammals, we used a mouse model to evaluate the relative virulence of selected 2009 H1N1 viruses and compared them to a representative human triple-reassortant swine influenza virus that has circulated in pigs in the United States for over a decade preceding the current pandemic. Additional comparisons were made with the reconstructed 1918 virus, a 1976 H1N1 swine influenza virus, and a highly pathogenic H5N1 virus. Mice were inoculated intranasally with each virus and monitored for morbidity, mortality, viral replication, hemostatic parameters, cytokine production, and lung histology. All 2009 H1N1 viruses replicated efficiently in the lungs of mice and possessed a high degree of infectivity but did not cause lethal disease or exhibit extrapulmonary virus spread. Transient weight loss, lymphopenia, and proinflammatory cytokine and chemokine production were present following 2009 H1N1 virus infection, but these levels were generally muted compared with a triple-reassortant swine virus and the 1918 virus. 2009 H1N1 viruses isolated from fatal cases did not demonstrate enhanced virulence in this model compared with isolates from mild human cases. Histologically, infection with the 2009 viruses resulted in lesions in the lung varying from mild to moderate bronchiolitis with occasional necrosis of bronchiolar epithelium and mild to moderate peribronchiolar alveolitis. Taken together, these studies demonstrate that the 2009 H1N1 viruses exhibited mild to moderate virulence in mice compared with highly pathogenic viruses.


2010 ◽  
Vol 49 (179) ◽  
Author(s):  
M Khadka

The family Orthomyxoviridae consists of Influenza A virus which is negative sense single stranded virus. The genome of the virus is segmented and possesses a peculiar trait of genetic reassortment. The influenza virus on its envelop consists of the antigenic glycoprotein like haemagglutinin (HA) and neuraminidase (NA). The changes in those glycoprotein components due to antigenic shift and antigenic drift leads to the development of new strain of Influenza A viruses. Now the novel swine influenza A/H1N1 strain has been detected from different parts of the world which is causing pandemic. World Health Organization has declared the pandemic phase six and more than 60 countries have reported the cases of novel influenza A/H1N1 strain including Nepal. As the disease is spreading world wide, it is a major public health concern for all the countries. And especially the developing countries like Nepal should immediately respond to the situation and should be well prepared to combat the disease before the disease spreads to enough population. Keywords: pandemic, public health, reassortment, swine influenza A/H1N1.


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