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Evidence-Based Supplement Research
Evidence-Based Supplement Research

Impact of Streptococcus salivarius K12 on Nasopharyngeal and Saliva Microbiome: A Randomized Controlled Trial.

  • 2020-12-08
  • The Pediatric infectious disease journal 40(5)
    • Suvi Sarlin
    • Mysore V Tejesvi
    • Jenni Turunen
    • Petri Vänni
    • Tytti Pokka
    • Marjo Renko
    • Terhi Tapiainen

Study Design

Type
Randomized Controlled Trial (RCT)
Sample size
n = 121
Population
121 children attending daycare
Methods
Randomized allocation to receive oral K12 product for 1 month or no treatment; saliva and nasopharyngeal samples at entry, 1 and 2 months; 16S sequencing
Blinding
Open-label
Duration
1 month
Funding
Unclear
  • Large Human Trial

Background

Probiotic lactobacilli have been ineffective in preventing acute otitis media. In contrast to lactobacilli, alpha-hemolytic streptococci belong to the core microbiome of nasopharynx.

Methods

We investigated the effects of Streptococcus salivarius K12 probiotic on the saliva and nasopharyngeal microbiome in 121 children attending daycare. Children were randomly allocated to receive oral K12 product for 1 month or no treatment. We obtained saliva and nasopharyngeal samples at study entry, at 1 and 2 months. The next-generation sequencing of the bacterial 16S gene was performed.

Results

After the intervention, the diversity of saliva or nasopharyngeal microbiome did not differ between groups. The proportion of children with any otopathogen did not differ between the groups. At 1 month, the abundance of otopathogens in nasopharynx was lower in K12 group compared with that in control children (34% vs. 55%, P = 0.037). When we compared each otopathogen separately, Moraxella was the only group lower in the treatment group. We could not verify the reduction of Moraxella when an alternative Human Oral Microbiome Database taxonomy database was used. In children receiving K12 product, the mean abundance of S. salivarius was greater in saliva after the intervention (0.9% vs. 2.0%, P = 0.009).

Conclusions

The use of S. salivarius K12 probiotic appeared to be safe because it did not disrupt the normal microbiome in young children. Even though a short-term colonization of S. salivarius was observed in the saliva, the impact of S. salivarius K12 probiotic on the otopathogens in nasopharyngeal microbiome remained uncertain.

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