Outbreak of Variant Influenza A(H3N2) Virus in the United States

Details

• Alternative Title:
  Clin Infect Dis
• Personal Author:
  Jhung, Michael A. ; Epperson, Scott ; Biggerstaff, Matthew ; Allen, Donna ; Balish, Amanda ; Barnes, Nathelia ; Beaudoin, Amanda ; Berman, LaShondra ; Bidol, Sally ; Blanton, Lenee ; Blythe, David ; Brammer, Lynnette ; D’Mello, Tiffany ; Danila, Richard ; Davis, William ; de Fijter, Sietske ; DiOrio, Mary ; Durand, Lizette O. ; Emery, Shannon ; Fowler, Brian ; Garten, Rebecca ; Grant, Yoran ; Greenbaum, Adena ; Gubareva, Larisa ; Havers, Fiona ; Haupt, Thomas ; House, Jennifer ; Ibrahim, Sherif ; Jiang, Victoria ; Jain, Seema ; Jernigan, Daniel ; Kazmierczak, James ; Klimov, Alexander ; Lindstrom, Stephen ; Longenberger, Allison ; Lucas, Paul ; Lynfield, Ruth ; McMorrow, Meredith ; Moll, Maria ; Morin, Craig ; Ostroff, Stephen ; Page, Shannon L. ; Park, Sarah Y. ; Peters, Susan ; Quinn, Celia ; Reed, Carrie ; Richards, Shawn ; Scheftel, Joni ; Simwale, Owen ; Shu, Bo ; Soyemi, Kenneth ; Stauffer, Jill ; Steffens, Craig ; Su, Su ; Torso, Lauren ; Uyeki, Timothy M. ; Vetter, Sara ; Villanueva, Julie ; Wong, Karen K. ; Shaw, Michael ; Bresee, Joseph S. ; Cox, Nancy ; Finelli, Lyn
• Description:
  Background
  
  Variant influenza virus infections are rare but may have pandemic potential if person-to-person transmission is efficient. We describe the epidemiology of a multistate outbreak of an influenza A(H3N2) variant virus (H3N2v) first identified in 2011.
  
  Methods
  
  We identified laboratory-confirmed cases of H3N2v and used a standard case report form to characterize illness and exposures. We considered illness to result from person-to-person H3N2v transmission if swine contact was not identified within 4 days prior to illness onset.
  
  Results
  
  From 9 July to 7 September 2012, we identified 306 cases of H3N2v in 10 states. The median age of all patients was 7 years. Commonly reported signs and symptoms included fever (98%), cough (85%), and fatigue (83%). Sixteen patients (5.2%) were hospitalized, and 1 fatal case was identified. The majority of those infected reported agricultural fair attendance (93%) and/or contact with swine (95%) prior to illness. We identified 15 cases of possible person-to-person transmission of H3N2v. Viruses recovered from patients were 93%–100% identical and similar to viruses recovered from previous cases of H3N2v. All H3N2v viruses examined were susceptible to oseltamivir and zanamivir and resistant to adamantane antiviral medications.
  
  Conclusions
  
  In a large outbreak of variant influenza, the majority of infected persons reported exposures, suggesting that swine contact at an agricultural fair was a risk for H3N2v infection. We identified limited person-to-person H3N2v virus transmission, but found no evidence of efficient or sustained person-to-person transmission. Fair managers and attendees should be aware of the risk of swine-to-human transmission of influenza viruses in these settings.
  
  
• Keywords:
  Adolescent Adult Aged Child Child, Preschool Contact Tracing Disease Outbreaks Female Hospitalization Humans Infant Influenza Influenza, Human Influenza A Virus, H3N2 Subtype Male Middle Aged Outbreak Pandemic United States Variant Influenza Young Adult

  More +
• Source:
  Clin Infect Dis. 57(12):1703-1712
• Pubmed ID:
  24065322
• Pubmed Central ID:
  PMC5733625
• Document Type:
  Journal Article
• Funding:
  CC999999/Intramural CDC HHSUnited States/
• Volume:
  57
• Issue:
  12
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:a01408f00a4efab8fd0262451f5ec59e93338ec4a3a24df9a6087cb9609d6617
• Download URL:
  https://stacks.cdc.gov/view/cdc/50566/cdc_50566_DS1.pdf
• File Type:
  [PDF - 740.53 KB ]