Volume 16, Number 1—January 2010
Dispatch
Serologic Cross-Reactivity with Pandemic (H1N1) 2009 Virus in Pigs, Europe
Table
Serologic cross-reactivity between North American H1 SIVs and pandemic (H1N1) 2009 virus after experimental infection and/or immunization of pigs by various methods with European SIVs*
| Group | No. pigs | Range of antibody titers of positive animals (no. pigs with HI antibody titers ≥10) |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| European SIVs |
North American H1 SIVs |
Pandemic (H1N1) 2009 cH1† | |||||||
| Swine/ Belgium/ 98 (H1N1) avH1† | Swine/ Gent/99 (H1N2) huH1† | Swine/ Flanders/98 (H3N2) huH3† | Swine/ Iowa/2004 (H1N1) cH1† | Swine/ Ontario/ 2004 (H1N1) cH1† | Swine/ Indiana/99 (H1N2) cH1† | ||||
| Infection‡ | |||||||||
| H1N1 (avH1†) | 6 | 40–160 (6) | –§ | – | – | – | – | 10 (1) | |
| H1N2 (huH1†) | 6 | – | 40–160 (6) | – | – | – | – | – | |
| H1N1 (avH1†)- 4w - H1N2 (huH1†) | 5 | 80–160 (5) | 20–40 (5) | – | 20 (4) | 10–20 (5) | 10–20 (5) | 20–40 (5) | |
| H1N2 (huH1†)- 4w - H1N1 (avH1†) | 4 | 80–160 (4) | 160–320 (4) | 10 (3) | 10–40 (4) | 20–80 (4) | 20–40 (4) | 20–160 (4) | |
| H1N1 (avH1†)- 4w -
H3N2 (huH3†) |
6 |
40–160 (6) |
– |
20–80 (6) |
– |
10–40 (3) |
10–20 (4) |
10–40 (6) |
|
| Double vaccination¶ | |||||||||
| New Jersey/8/76 (H1N1, cH1†) | 6 | 10–40 (6) | 10 (1) | 10–80 (5) | 80–160 (6) | 20–80 (6) | 80–320 (6) | 10–20 (5) | |
| Swine/Netherlands/25/ 80 (H1N1, avH1†) | 6 | 10–40 (6) | 10 (1) | 10–160 (6) | 20–40 (5) | 10–80 (6) | 10–40 (6) | 10 (3) | |
| Swine/Belgium/230/92 (H1N1, avH1†) | 6 | 20–640 (6) | 10–20 (2) | 20–320 (6) | 10–320 (5) | 10–320 (6) | 10–160 (5) | 10–640 (5) | |
| Swine/Haselunne/2617/
2003 (H1N1, avH1†) |
6 |
10–40 (6) |
40–160 (6) |
20 (6) |
– |
20 (1) |
10–20 (5) |
10 (1) |
|
| Infection# followed by single vaccination | |||||||||
| H1N1 (avH1†)- 4w -
New Jersey/8/76 |
6 |
640–2,560 (6) |
10 (3) |
10 (1) |
40–80 (6) |
40–80 (6) |
80–320 (6) |
40–80 (6) |
|
| Hyperimmunization** | |||||||||
| H1N1 (avH1†) | 3 | 320–1,280 (3) | 10–20 (2) | – | 40–160 (3) | 40–160 (3) | 40–80 (3) | 40–160 (3) | |
| H1N2 (huH1†) | 3 | 40 (1) | 320–1,280 (3) | – | 20 (1) | 10–80 (2) | 40 (1) | 80 (1) | |
| H3N2 (huH3†) | 3 | – | – | 160–640 (3) | – | – | – | – | |
*SIV, swine influenza virus.
†Phylogenetic lineage of the hemagglutinin gene: c, classical swine; hu, human; av, avian.
‡Infection with swine/Belgium/1/98 (H1N1), swine/Gent/7625/99 (H1N2), or swine/Flanders/1/98 (H3N2).
§Antibody titers <10 in all pigs.
¶Only the influenza (H1N1) vaccine component is shown. The first 3 vaccines are bivalent (subtypes H1N1, H3N2); the fourth is trivalent (subtypes H1N1, H3N2, H1N2).
#Infection with swine/Belgium/1/98 (H1N1).
**Each individual pig was hyperimmunized with a different European SIV isolate: subtype H1N1 viruses were swine/Finistère/2899/82, swine/Belgium/1/98, and swine/Gent/132/2005; subtype H1N2 viruses were swine/Scotland/410440/94, swine/Gent/7625/99, and swine/Gent/177/2002; subtype H3N2 viruses were swine/Gent/1/84, swine/Flanders/1/98, and swine/Gent/131/2005.