Article

Dual infection of novel influenza viruses A/H1N1 and A/H3N2 in a cluster of Cambodian patients.

Naval Health Research Center, San Diego, California, USA.
The American journal of tropical medicine and hygiene (Impact Factor: 2.74). 11/2011; 85(5):961-3. DOI: 10.4269/ajtmh.2011.11-0098
Source: PubMed

ABSTRACT During the early months of 2009, a novel influenza A/H1N1 virus (pH1N1) emerged in Mexico and quickly spread across the globe. In October 2009, a 23-year-old male residing in central Cambodia was diagnosed with pH1N1. Subsequently, a cluster of four influenza-like illness cases developed involving three children who resided in his home and the children's school teacher. Base composition analysis of internal genes using reverse transcriptase polymerase chain reaction and electrospray ionization mass spectrometry revealed that specimens from two of the secondary victims were coinfected with influenza A/H3N2 and pH1N1. Phylogenetic analysis of the hemagglutinin genes from these isolated viruses showed that they were closely related to existing pH1N1 and A/H3N2 viruses circulating in the region. Genetic recombination was not evident within plaque-purified viral isolates on full genome sequencing. This incident confirms dual influenza virus infections and highlights the risk of zoonotic and seasonal influenza viruses to coinfect and possibly, reassort where they cocirculate.

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Available from: Shan Putnam, Aug 10, 2015
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    • "For baseline values of model parameters we assume that among the contacts between co-infected people with the susceptible, 80% generate single infections equally with strain 1 or strain 2, and 20% to dual infections (soˇd = 0.20 × ˇ 1 = 0.075). Because co-infections were rarely reported (Peacey et al., 2010; Myers et al., 2011), data for their epidemiological and dynamics characteristics are lacking. Here we assume that the infectious period of co-infection is longer than either single infection with 1/ d = 6 days and its severity is double that of the single infection. "
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    03/2013; 5(1):20-33. DOI:10.1016/j.epidem.2012.10.003
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    • "For baseline values of model parameters we assume that among the contacts between co-infected people with the susceptible, 80% generate single infections equally with strain 1 or strain 2, and 20% to dual infections (soˇd = 0.20 × ˇ 1 = 0.075). Because co-infections were rarely reported (Peacey et al., 2010; Myers et al., 2011), data for their epidemiological and dynamics characteristics are lacking. Here we assume that the infectious period of co-infection is longer than either single infection with 1/ d = 6 days and its severity is double that of the single infection. "
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