Antigenic Characterization of H3 Subtypes of Avian Influenza A Viruses from North America.
Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts, including avian, swine, equine, canine, and sea mammal species. These H3 viruses are both antigenically and genetically diverse. Here, we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about four units, and each unit corresponds to a 2 log&thinsp;2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable.
A Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
Elizabeth
E
Bailey
A Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
Li-Ping
LP
Long
A Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
Nan
N
Zhao
B U.S. Geological Survey National Wildlife Health Center, Madison, WI 53711.
Jeffrey S
JS
Hall
C National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO 80521.
John A
JA
Baroch
D Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210.
Jacqueline
J
Nolting
E Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
Lucy
L
Senter
F Mississippi Field Station, National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Mississippi State, MI 39762.
Frederick L
FL
Cunningham
A Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
G Todd
GT
Pharr
A Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
Larry
L
Hanson
D Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210.
Richard
R
Slemons
C National Wildlife Research Center, Wildlife Services, Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO 80521.
Thomas J
TJ
DeLiberto
A Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762.
Xiu-Feng
XF
Wan
D000818:Animals; D000835:Animals, Wild / Q000821:virology; D046090:Anseriformes / Q000145:classification / Q000821:virology; D000940:Antigenic Variation; D002642:Chick Embryo; D002645:Chickens; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D009980:Influenza A virus / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000302:isolation & purification; D005585:Influenza in Birds / Q000821:virology*; D007251:Influenza, Human / Q000821:virology; D009656:North America; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D011201:Poultry Diseases / Q000821:virology; D013552:Swine; D013553:Swine Diseases / Q000821:virology
H3; antigenic cartography; avian influenza virus; influenza A virus; low pathogenic avian influenza virus; migratory flyway; migratory waterfowl