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J Clin Virol. 2015 Nov 5;73:108-111. doi: 10.1016/j.jcv.2015.11.008. [Epub ahead of print]
Natural co-infection of influenza A/H3N2 and A/H1N1pdm09 viruses resulting in a reassortant A/H3N2 virus.
Rith S1, Chin S2, Sar B3, Y P1, Horm SV1, Ly S4, Buchy P1, Dussart P1, Horwood PF5.
Author information
Abstract
BACKGROUND:
Despite annual co-circulation of different subtypes of seasonal influenza, co-infections between different viruses are rarely detected. These co-infections can result in the emergence of reassortant progeny.
STUDY DESIGN:
We document the detection of an influenza co-infection, between influenza A/H3N2 with A/H1N1pdm09 viruses, which occurred in a 3 year old male in Cambodia during April 2014. Both viruses were detected in the patient at relatively high viral loads (as determined by real-time RT-PCR CT values), which is unusual for influenza co-infections. As reassortment can occur between co-infected influenza A strains we isolated plaque purified clonal viral populations from the clinical material of the patient infected with A/H3N2 and A/H1N1pdm09.
RESULTS:
Complete genome sequences were completed for 7 clonal viruses to determine if any reassorted viruses were generated during the influenza virus co-infection. Although most of the viral sequences were consistent with wild-type A/H3N2 or A/H1N1pdm09, one reassortant A/H3N2 virus was isolated which contained an A/H1N1pdm09 NS1 gene fragment. The reassortant virus was viable and able to infect cells, as judged by successful passage in MDCK cells, achieving a TCID50 of 104/ml at passage number two. There is no evidence that the reassortant virus was transmitted further. The co-infection occurred during a period when co-circulation of A/H3N2 and A/H1N1pdm09 was detected in Cambodia.
CONCLUSIONS:
It is unclear how often influenza co-infections occur, but laboratories should consider influenza co-infections during routine surveillance activities.
Copyright ? 2015 Z. Published by Elsevier B.V. All rights reserved.
KEYWORDS:
A/H1N1pdm09; A/H3N2; Co-infection; Influenza; Reassortant; Reassortment; Seasonal
PMID: 26590689 [PubMed - as supplied by publisher] Free full text
Natural co-infection of influenza A/H3N2 and A/H1N1pdm09 viruses resulting in a reassortant A/H3N2 virus.
Rith S1, Chin S2, Sar B3, Y P1, Horm SV1, Ly S4, Buchy P1, Dussart P1, Horwood PF5.
Author information
Abstract
BACKGROUND:
Despite annual co-circulation of different subtypes of seasonal influenza, co-infections between different viruses are rarely detected. These co-infections can result in the emergence of reassortant progeny.
STUDY DESIGN:
We document the detection of an influenza co-infection, between influenza A/H3N2 with A/H1N1pdm09 viruses, which occurred in a 3 year old male in Cambodia during April 2014. Both viruses were detected in the patient at relatively high viral loads (as determined by real-time RT-PCR CT values), which is unusual for influenza co-infections. As reassortment can occur between co-infected influenza A strains we isolated plaque purified clonal viral populations from the clinical material of the patient infected with A/H3N2 and A/H1N1pdm09.
RESULTS:
Complete genome sequences were completed for 7 clonal viruses to determine if any reassorted viruses were generated during the influenza virus co-infection. Although most of the viral sequences were consistent with wild-type A/H3N2 or A/H1N1pdm09, one reassortant A/H3N2 virus was isolated which contained an A/H1N1pdm09 NS1 gene fragment. The reassortant virus was viable and able to infect cells, as judged by successful passage in MDCK cells, achieving a TCID50 of 104/ml at passage number two. There is no evidence that the reassortant virus was transmitted further. The co-infection occurred during a period when co-circulation of A/H3N2 and A/H1N1pdm09 was detected in Cambodia.
CONCLUSIONS:
It is unclear how often influenza co-infections occur, but laboratories should consider influenza co-infections during routine surveillance activities.
Copyright ? 2015 Z. Published by Elsevier B.V. All rights reserved.
KEYWORDS:
A/H1N1pdm09; A/H3N2; Co-infection; Influenza; Reassortant; Reassortment; Seasonal
PMID: 26590689 [PubMed - as supplied by publisher] Free full text