scholarly journals Unseasonal Transmission of H3N2 Influenza A Virus During the Swine-Origin H1N1 Pandemic

2010 ◽  
Vol 84 (11) ◽  
pp. 5715-5718 ◽  
Author(s):  
Elodie Ghedin ◽  
David E. Wentworth ◽  
Rebecca A. Halpin ◽  
Xudong Lin ◽  
Jayati Bera ◽  
...  

ABSTRACT The initial wave of swine-origin influenza A virus (pandemic H1N1/09) in the United States during the spring and summer of 2009 also resulted in an increased vigilance and sampling of seasonal influenza viruses (H1N1 and H3N2), even though they are normally characterized by very low incidence outside of the winter months. To explore the nature of virus evolution during this influenza “off-season,” we conducted a phylogenetic analysis of H1N1 and H3N2 sequences sampled during April to June 2009 in New York State. Our analysis revealed that multiple lineages of both viruses were introduced and cocirculated during this time, as is typical of influenza virus during the winter. Strikingly, however, we also found strong evidence for the presence of a large transmission chain of H3N2 viruses centered on the south-east of New York State and which continued until at least 1 June 2009. These results suggest that the unseasonal transmission of influenza A viruses may be more widespread than is usually supposed.

2021 ◽  
Author(s):  
Erica Lasek-Nesselquist ◽  
Navjot Singh ◽  
Alexis Russell ◽  
Daryl Lamson ◽  
John Kelly ◽  
...  

AbstractNew York State, in particular the New York City metropolitan area, was the early epicenter of the SARS-CoV-2 pandemic in the United States. Similar to initial pandemic dynamics in many metropolitan areas, multiple introductions from various locations appear to have contributed to the swell of positive cases. However, representation and analysis of samples from New York regions outside the greater New York City area were lacking, as were SARS-CoV-2 genomes from the earliest cases associated with the Westchester County outbreak, which represents the first outbreak recorded in New York State. The Wadsworth Center, the public health laboratory of New York State, sought to characterize the transmission dynamics of SARS-CoV-2 across the entire state of New York from March to September with the addition of over 600 genomes from under-sampled and previously unsampled New York counties and to more fully understand the breadth of the initial outbreak in Westchester County. Additional sequencing confirmed the dominance of B.1 and descendant lineages (collectively referred to as B.1.X) in New York State. Community structure, phylogenetic, and phylogeographic analyses suggested that the Westchester outbreak was associated with continued transmission of the virus throughout the state, even after travel restrictions and the on-pause measures of March, contributing to a substantial proportion of the B.1 transmission clusters as of September 30th, 2020.


2018 ◽  
Vol 13 (1) ◽  
pp. 83-90 ◽  
Author(s):  
Marcus J. Bolton ◽  
Eugenio J. Abente ◽  
Divya Venkatesh ◽  
Jered A. Stratton ◽  
Michael Zeller ◽  
...  

2015 ◽  
Vol 129 (2) ◽  
pp. 183
Author(s):  
Daniel F. Brunton

Six populations of Great Plains Ladies’-tresses (Spiranthes magnicamporum Sheviak) have recently been discovered in three locations east of the lower Great Lakes region of Canada and the United States. The possible occurrence of S. cernua × magnicamporum hybrids was detected at one New York site. These discoveries are from both natural alvar and disturbed meadow and shore sites. The new records suggest that S. magnicamporum occurs more widely than was suspected previously, its presence perhaps masked by its similarity to the common S. cernua (L.) Richard. Eastern occurrences may represent a combination of post-glacial relict populations, responses to climate change, and the results of long-distance dispersal events. These range extensions constitute the most easterly known populations of S. magnicamporum in North America. They also represent new records for New York State (including Jefferson and St. Lawrence Counties) and for the City of Ottawa in Ontario.


Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1171
Author(s):  
Yaron Drori ◽  
Jasmine Jacob-Hirsch ◽  
Rakefet Pando ◽  
Aharona Glatman-Freedman ◽  
Nehemya Friedman ◽  
...  

Influenza viruses and respiratory syncytial virus (RSV) are respiratory viruses that primarily circulate worldwide during the autumn and winter seasons. Seasonal surveillance has shown that RSV infection generally precedes influenza. However, in the last four winter seasons (2016–2020) an overlap of the morbidity peaks of both viruses was observed in Israel, and was paralleled by significantly lower RSV infection rates. To investigate whether the influenza A virus inhibits RSV, human cervical carcinoma (HEp2) cells or mice were co-infected with influenza A and RSV. Influenza A inhibited RSV growth, both in vitro and in vivo. Mass spectrometry analysis of mouse lungs infected with influenza A identified a two-wave pattern of protein expression upregulation, which included members of the interferon-induced protein with the tetratricopeptide (IFITs) family. Interestingly, in the second wave, influenza A viruses were no longer detectable in mouse lungs. In addition, knockdown and overexpression of IFITs in HEp2 cells affected RSV multiplicity. In conclusion, influenza A infection inhibits RSV infectivity via upregulation of IFIT proteins in a two-wave modality. Understanding the immune system involvement in the interaction between influenza A and RSV viruses will contribute to the development of future treatment strategies against these viruses.


2020 ◽  
Vol 13 (626) ◽  
pp. eaaz3381 ◽  
Author(s):  
Yongquan He ◽  
Weihui Fu ◽  
Kangli Cao ◽  
Qian He ◽  
Xiangqing Ding ◽  
...  

Type I interferons (IFNs) are the first line of defense against viral infection. Using a mouse model of influenza A virus infection, we found that IFN-κ was one of the earliest responding type I IFNs after infection with H9N2, a low-pathogenic avian influenza A virus, whereas this early induction did not occur upon infection with the epidemic-causing H7N9 virus. IFN-κ efficiently suppressed the replication of various influenza viruses in cultured human lung cells, and chromodomain helicase DNA binding protein 6 (CHD6) was the major effector for the antiviral activity of IFN-κ, but not for that of IFN-α or IFN-β. The induction of CHD6 required both of the type I IFN receptor subunits IFNAR1 and IFNAR2, the mitogen-activated protein kinase (MAPK) p38, and the transcription factor c-Fos but was independent of signal transducer and activator of transcription 1 (STAT1) activity. In addition, we showed that pretreatment with IFN-κ protected mice from lethal influenza viral challenge. Together, our findings identify an IFN-κ–specific pathway that constrains influenza A virus and provide evidence that IFN-κ may have potential as a preventative and therapeutic agent against influenza A virus.


2018 ◽  
Vol 92 (22) ◽  
Author(s):  
Eugenio J. Abente ◽  
Daniela S. Rajao ◽  
Jefferson Santos ◽  
Bryan S. Kaplan ◽  
Tracy L. Nicholson ◽  
...  

ABSTRACTInfluenza A viruses in swine (IAV-S) circulating in the United States of America are phylogenetically and antigenically distinct. A human H3 hemagglutinin (HA) was introduced into the IAV-S gene pool in the late 1990s, sustained continued circulation, and evolved into five monophyletic genetic clades, H3 clades IV-A to -E, after 2009. Across these phylogenetic clades, distinct antigenic clusters were identified, with three clusters (cyan, red, and green antigenic cluster) among the most frequently detected antigenic phenotypes (Abente EJ, Santos J, Lewis NS, Gauger PC, Stratton J, et al. J Virol 90:8266–8280, 2016,https://doi.org/10.1128/JVI.01002-16). Although it was demonstrated that antigenic diversity of H3N2 IAV-S was associated with changes at a few amino acid positions in the head of the HA, the implications of this diversity for vaccine efficacy were not tested. Using antigenically representative H3N2 viruses, we compared whole inactivated virus (WIV) and live-attenuated influenza virus (LAIV) vaccines for protection against challenge with antigenically distinct H3N2 viruses in pigs. WIV provided partial protection against antigenically distinct viruses but did not prevent virus replication in the upper respiratory tract. In contrast, LAIV provided complete protection from disease and virus was not detected after challenge with antigenically distinct viruses.IMPORTANCEDue to the rapid evolution of the influenza A virus, vaccines require continuous strain updates. Additionally, the platform used to deliver the vaccine can have an impact on the breadth of protection. Currently, there are various vaccine platforms available to prevent influenza A virus infection in swine, and we experimentally tested two: adjuvanted-whole inactivated virus and live-attenuated virus. When challenged with an antigenically distinct virus, adjuvanted-whole inactivated virus provided partial protection, while live-attenuated virus provided effective protection. Additional strategies are required to broaden the protective properties of inactivated virus vaccines, given the dynamic antigenic landscape of cocirculating strains in North America, whereas live-attenuated vaccines may require less frequent strain updates, based on demonstrated cross-protection. Enhancing vaccine efficacy to control influenza infections in swine will help reduce the impact they have on swine production and reduce the risk of swine-to-human transmission.


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