Immunization against influenza during the 2005/2006 epidemic season and the humoral response in children with diagnosed inflammatory bowel disease (IBD).
BACKGROUND
Patients with inflammatory bowel disease (IBD) who are treated long-term with immunosuppressive drugs can experience a decrease in their overall resistance to infections, including influenza. The purpose of this study was to evaluate the humoral response in children with IBD after being vaccinated against influenza.


METHODS
Children with IBD were vaccinated with split inactivated vaccine. They were divided into 2 groups: children treated with anti-inflammatory medications and children treated with 5-acetylsalicylic acid along with immunomodulatory therapy. Antihemagglutinin (anti-HA) and antineuraminidase (anti-NA) antibodies were assessed before vaccination and 1 and 6 months after vaccination.


RESULTS
Anti-HA and anti-NA antibodies 1 and 6 months after vaccination were higher than before vaccination. In the patients treated with anti-inflammatory medications, the protection rate (PR) attained the highest level for antigens A/H1N1 and B 6 months after vaccination. However, for A/H3N2 the result was 88.9% at 1 and 6 months after vaccination. In the patients who received immunomodulatory medications, the highest PR was noted 6 months after vaccination (47.6-90.5%). The response rate (RR) in patients who were treated with the anti-inflammatory medications alone remained the same 1 and 6 months after vaccination. In patients who received the immunomodulatory regimen, the highest RR was recorded 6 months after vaccination (47.6-76.2%).


CONCLUSIONS
Response to vaccination was satisfactory, although not for all vaccine antigens, especially in patients treated with immunomodulatory medications. The higher levels of RP and RR 6 months after vaccination compared with 1 month after vaccination lends support to the argument that IBD patients should be vaccinated as soon as vaccine is available in a season.
Romanowska
Magdalena
M
Department of Influenza Research, National Influenza Center, National Institute of Public Health-National Institute of Hygiene, Warsaw, Poland. nic@pzh.gov.pl
Banaszkiewicz
Aleksandra
A
Nowak
Iwona
I
Radzikowski
Andrzej
A
Brydak
Lidia B
LB
D000293:Adolescent; D000914:Antibodies, Viral / Q000276:immunology; D002648:Child; D058872:Epidemics / Q000517:prevention & control*; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000276:immunology; D006801:Humans; D056724:Immunity, Humoral / Q000276:immunology*; D007114:Immunization; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis* / Q000276:immunology* / Q000821:virology; D009980:Influenza A virus / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology; D007251:Influenza, Human / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control*; D009439:Neuraminidase / Q000276:immunology; D011044:Poland / Q000453:epidemiology; D012621:Seasons
D000914:Antibodies, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; D009439:Neuraminidase