Haemophilus influenzae oral vaccination against acute bronchitis.
OBJECTIVE
To assess the effects of an oral whole cell nontypeable Haemophilus influenzae (NTHi) vaccine in protecting against recurrent episodes of bronchitis.


METHODS
We searched the Cochrane trials register, MEDLINE, Extramed, ISI Current Contents, Carl Uncover and contacted investigators of the studies.


METHODS
Randomised trials comparing the effects of an oral monobacterial NTHi vaccine on patients with recurrent exacerbations of bronchitis were included when there was overt matching of the vaccine and placebo groups on clinical grounds.


METHODS
Two reviewers extracted data and assessed trial quality independently from original records and publications for incidence and severity of bronchitis episodes and carriage rate of nontypeable Haemophilus influenzae in the upper respiratory tract every three months following vaccination.


RESULTS
Six trials were included in the study with a total of 440 participants. Oral vaccination using a monobacterial whole cell killed nontypeable Haemophilus influenzae significantly reduced the incidence of bronchitic episodes at 3 months (Weighted Mean Difference [WMD] 6.694; 95% confidence interval [CI] 6.963 - -6.424; p < 0.01) and 6 months (WMD 4.496; 95% CI 4.664 - -4.327; p < 0.01) following vaccination. The effect diminished by 9 months. The severity of exacerbations in the treatment group was likewise reduced by 58% at 3 months (Peto OR = 0. 42; 95% CI 0.16 1.13), and 65% at 6 months (Peto OR = 0.35; 95% CI 0. 16 0.75) following vaccination.


CONCLUSIONS
Vaccination, in the autumn, of patients with recurrent exacerbations of bronchitis reduced the number and severity of exacerbations over the winter months. A large clinical trial to assess longer term prognosis needs to be completed.
Foxwell
A R
AR
Division of Science & Design, University of Canberra, ACT 2601, Ausatalia. foxwell@science.canberra.edu.au
Cripps
A W
AW
D000208:Acute Disease; D001991:Bronchitis / Q000517:prevention & control*; D018073:Haemophilus Vaccines; D006801:Humans; D012008:Recurrence
D018073:Haemophilus Vaccines