Association of an early respiratory syncytial virus infection and atopic allergy.
BACKGROUND
Respiratory syncytial virus (RSV) causes postbronchiolitic wheezing but its role in allergic sensitization is controversial. The purpose of the study was to examine the effect of an early RSV infection on allergic sensitization.


METHODS
Seventy-six subjects were examined 6-10 years after hospitalization for RSV infection during the first year of life. Fifty-one subjects (68%) attended clinical studies and 25 filled in a questionnaire. The study protocol included lung function, skin-prick and blood tests. The controls were matched for birth date and sex.


RESULTS
Eight per cent of the subjects and 37% of the controls had at least one positive skin-prick test (SPT) (difference -35%, 95% CI -50 to -19%, P < 0.0001). Allergic rhinitis, atopic dermatitis and asthma occurred as often in both groups, but asthma had been diagnosed significantly earlier in the subjects than in the controls [mean age 3.0 years (SD 2.6) and 5.6 years (SD 3.0), difference 2.6 years, 95% CI 0.57-4.65, P = 0.014]. In a logistic regression analysis, RSV infection was associated with negative SPTs.


CONCLUSIONS
An early RSV infection results in reduction of SPT positivity but not of occurrence of atopic diseases. This finding might explain why there is less atopic sensitization in countries with a greater probability of acquiring RSV infection at an early age.
Juntti
H
H
Department of Pediatrics, University of Oulu, PO Box 5000, FIN-90014 Oulu, Finland.
Kokkonen
J
J
Dunder
T
T
Renko
M
M
Niinimäki
A
A
Uhari
M
M
D017668:Age of Onset; D001249:Asthma / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D003876:Dermatitis, Atopic / Q000453:epidemiology; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D015994:Incidence; D007223:Infant; D016015:Logistic Models; D008297:Male; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology*; D012220:Rhinitis / Q000453:epidemiology / Q000209:etiology; D012882:Skin Tests; D013997:Time Factors