Scott Epperson, etc.,al. Human Infections With Influenza A(H3N2) Variant Virus in the United States, 2011–2012. Clin Infect Dis. (2013) 57 (suppl 1): S4-S11 doi:
Background.During August 2011–April 2012, 13 human infections with influenza A(H3N2) variant (H3N2v) virus were identified in the United States; 8 occurred in the prior 2 years. This virus differs from previous variant influenza viruses in that it contains the matrix (M) gene from the Influenza A(H1N1)pdm09 pandemic influenza virus.
Methods.A case was defined as a person with laboratory-confirmed H3N2v virus infection. Cases and contacts were interviewed to determine exposure to swine and other animals and to assess potential person-to-person transmission.
Results.Median age of cases was 4 years, and 12 of 13 (92%) were children. Pig exposure was identified in 7 (54%) cases. Six of 7 cases with swine exposure (86%) touched pigs, and 1 (14%) was close to pigs without known direct contact. Six cases had no swine exposure, including 2 clusters of suspected person-to-person transmission. All cases had fever; 12 (92%) had respiratory symptoms, and 3 (23%) were hospitalized for influenza. All 13 cases recovered.
Conclusions.H3N2v virus infections were identified at a high rate from August 2011 to April 2012, and cases without swine exposure were identified in influenza-like illness outbreaks, indicating that limited person-to-person transmission likely occurred. Variant influenza viruses rarely result in sustained person-to-person transmission; however, the potential for this H3N2v virus to transmit efficiently is of concern. With minimal preexisting immunity in children and the limited cross-protective effect from seasonal influenza vaccine, the majority of children are susceptible to infection with this novel influenza virus.
See Also:
Latest articles in those days:
- [preprint] Potential Pathways of Spread of Highly Pathogenic Avian Influenza A/H5N1 Clade 2.3.4.4b Across Dairy Farms in the United States 19 hours ago
- [preprint] The avian and human influenza A virus receptors sialic acid (SA)-α2,3 and SA-α2,6 are widely expressed in the bovine mammary gland 19 hours ago
- Repeatability and reproducibility of hunter-harvest sampling for avian influenza virus surveillance in Great Britain 19 hours ago
- The RBPome of influenza A virus NP-mRNA reveals a role for TDP-43 in viral replication 19 hours ago
- Novel Genotype of HA Clade 2.3.4.4b H5N8 Subtype High Pathogenicity Avian Influenza Virus Emerged at a Wintering Site of Migratory Birds in Japan, 2021/22 Winter 20 hours ago
[Go Top] [Close Window]