Effect of recolonisation with "interfering" α streptococci on recurrences of acute and secretory otitis media in children:: randomised placebo controlled trial

Objective To study the effect of recolonisation with a streptococci with the ability to inhibit the growth of otopathogens ("interfering" activity) on the recurrence of acute otitis media in susceptible children and the effect on the frequency of secretory otitis media. Design Double blind, randomised, placebo controlled study: Setting Ear, nose, and throat clinic with three doctors. Participants 130 children prone to otitis media aged between 6 months and 6 years, 108 of whom were eligible and followed for 3 months. Main outcome measures Recurrence of otitis media during follow up and a normal tympanic membrane at the last valid visit. Interventions Children with no recurrences during the last month received phenoxymethylpenicillin (n = 22), and those with a recurrence within 1 month received amoxicillin clavulanic acid (n = 86), both twice daily for 10 days. These were followed by a streptococcal or placebo solution sprayed into the nose for a further 10 days. At day 60 the same spray was started for another 10 days. Results At 3 months 22 children (42%) given the streptococcal spray were healthy and had a normal tympanic membrane compared with 12 (22%) of those given placebo. This difference was shown separately for recurrences of both acute otitis media and secretor) otitis media. Conclusions Selected bacteria with the ability to inhibit the growth of common otopathogens can be used to protect against recurrent acute otitis media and secretory otitis media in children.