A daily oral cavity probiotic with Streptococcus salivarius did not reduce the incidence of acute otitis media (AOM) in children in a placebo-controlled six-month trial,1 despite earlier evidence2 that it reduces the relative abundance of otopathogens in the nasopharyngeal mirobiome.
Suvi Sarlin, MD, Department of Pediatrics and Adolescent Medicine, Oulu University Hospital, Oulu Finland, and colleagues noted that a reduction in AOM has been demonstrated3 with an extemporaneously compounded, investigational α-streptococcal nasal spray, and hoped that the outcome might also be achieved with a commercially available oral cavity probiotic marketed for "ear, nose and throat health."
"Prevention of AOM plays a significant role in reducing the overall use of antibiotics in children," Sarlin and colleagues point out, noting that, except for pneumococcal conjugate and influenza vaccines, "current options for primary prevention of AOM are limited."
The trial was conducted in 50 day care centers in the Oulu region of Finland, with 827 children aged 1 to 6 years randomized in a 1:1 ratio to receive either a daily dose of an S salivarius K12 oral product (chewable tablet for children >3years or oral powder for younger) or placebo every evening after tooth brushing for 6 months.
Demographic characteristics were considered balanced between the two groups, and so any significant findings should be applicable to the larger population.Children were excluded from participation if receiving antimicrobial prophylaxis or for having immunodeficiency.
What You Need to Know
Daily oral cavity probiotics with Streptococcus salivarius did not reduce the incidence of acute otitis media (AOM) in children during a six-month trial.
The prevention of AOM is important for reducing antibiotic use in children, but current options for primary prevention are limited.
The study conducted in Finland involved 827 children aged 1 to 6 years, and the primary outcome was the proportion of children with at least one episode of AOM within 6 months, requiring antimicrobial therapy.
The primary outcome was the proportion of children with at least 1 episode of AOM within 6 months of randomization which required antimicrobial therapy, confirmed from the electronic national medical record and prescription register. Secondary outcomes included time to the first episode of AOM requiring antimicrobial therapy, the proportion of children with recurrent AOM, and the proportion of children receiving any antimicrobial therapy.
Sarlin and colleagues reported that 8.2% in the S salivarius group and 5.8% in the placebo group had at least 1 episode of AOM, which was not statistically significantly different."In the primary prevention of AOM S salivarius K12 oral products appeared to be ineffective," they concluded.
Differences between groups in secondary outcomes were either not statistically significant, or the occurrences were fewer than the study was statistical powered to distinguish.
The investigators speculate that a nasal spray solution might have been more effective than the oral preparations. They also note that the commercial product of S salivarius contained L rhamnosus GG and P shermanii, and the possibility that these might have interfered with the the probiotic effect of S salivarius.
On the other hand, Sarlin and colleagues speculate that S salivarius K12 alone may be insufficient to offsetting significant otopathogens such as Haemophilus influenzae and Moraxella catarrhalis which "may overcome its inhibitory effects by other direct or indirect methods yet unknown."
An additional qualification of the study was that it was conducted during the COVID-19 pandemic, with a corresponding low circulation of several respiratory viruses and a low incidence of AOM. "With a higher incidence of circulating respiratory viruses and therefore a higher incidence of AOM, it is possible that S salivarius K12 might have had a different effect," they suggested.
1. Sarlin S, Koskela U, Honkila M, et al. Streptococcus salivarius Probiotics to Prevent Acute Otitis Media in Children: A Randomized Clinical Trial. JAMA Netw Open. 2023;6(11):e2340608. doi:10.1001/jamanetworkopen.2023.40608
2.Sarlin S, Tejesvi MV, Turunen J, et al. Impact of Streptococcus salivarius K12 on Nasopharyngeal and Saliva Microbiome: A Randomized Controlled Trial. Pediatr Infect Dis J. 2021;40(5):394-402. doi:10.1097/INF.0000000000003016
3. Roos K, Håkansson EG, Holm S. Effect of recolonisation with "interfering" alpha streptococci on recurrences of acute and secretory otitis media in children: randomised placebo controlled trial. BMJ. 2001;322(7280):210-212. doi:10.1136/bmj.322.7280.210