Antigenic drift of H1N1 influenza A virus in pigs with and without passive immunity
Article first published online: 14 NOV 2013
© 2013 Blackwell Publishing Ltd
Influenza and Other Respiratory Viruses
Special Issue: Proceedings of the 2nd International Symposium on Neglected Influenza Viruses, Dublin, Ireland, 7-8 March 2013. Edited by: Thomas Chambers and Ariel Pereda. Publication of this supplement was supported by isirv.
Volume 7, Issue Supplement s4, pages 52–60, December 2013
How to Cite
2013) Antigenic drift of H1N1 influenza A virus in pigs with and without passive immunity. Influenza and Other Respiratory Viruses 7 (Suppl. 4), 52–60.et al. (
- Issue published online: 14 NOV 2013
- Article first published online: 14 NOV 2013
- National Institute of Allergy and Infectious Diseases and Department of Health and Human Services. Grant Number: HHSN266200700007C
- USDA Discretionary GAR. Grant Number: AES0060014
- College of Veterinary Medicine, University of Minnesota
- Antigenic drift;
- passive immunity;
- Swine influenza
The genetic and antigenic characteristics of influenza A viruses (IAV) within and between species change over time due to antigenic shift and drift. Although pigs are known to play a key role in the epidemiology of IAV between species, little is known about the molecular evolution of IAV hemagglutinin (HA) in pigs.
The aim of this study was to evaluate the HA drift of an H1N1 IAV after infecting weaned pigs with or without maternally derived passive immunity.
Three- to four-week-old piglets born either to vaccinated or unvaccinated sows were contact-infected upon exposure with an IAV-infected pig. Nasal swabs were collected daily from each pig and tested for IAV by RRT-PCR. Full-length HA sequences were obtained directly from positive nasal swabs and compared between groups.
Synonymous and non-synonymous mutations were detected in pigs with and without passive immunity. Most of the non-synonymous mutations occurred within the HA1 region of the HA. Changes within HA1 region were only identified in antigenic site B in pigs without passive immunity and in antigenic sites A, B, and D in pigs with passive immunity. However, there was no association between the immune status of the pig and the amino acid substitutions observed.
Overall, we demonstrated that amino acid substitutions within antigenic sites can happen in weaned pigs with or without passive immunity shortly after infection.