The three independent studies, gathered in a white paper released by New Zealand-based oral probiotics firm Blis Technologies Ltd., provide evidence that the strain may reduce the frequency and length of respiratory illness.
“We always say that the mouth is the gateway to the body and these studies help validate the role the oral microbiome plays to our overall health and immunity,” said John Hale, PhD, chief technology officer at Blis Technologies.
Little bacterial ‘bullets’
Developed by scientists at the University of Otago, New Zealand, BLIS K12 is a specific patented strain of Streptococcus salivarius (S. salivarius) first isolated from the mouth of a healthy child.
The commensal bacterium secretes powerful antimicrobial molecules, which the company describes as “little bacterial ‘bullets’ that inhibit the bad bacteria”. These are referred to as Bacteriocin-Like-Inhibitory-Substances or simply BLIS.
“Daily consumption of BLIS K12 helps to keep the bad bacteria out, optimizing your body’s natural ability to defend against airborne germs and potential threats,” Hale explained.
Blis Technologies introduced the strain as key ingredient in its ThroatHealth lozenges in 2002, clinically proven to reduce the reoccurrence of throat infections and tonsillitis by up to 90%. The company has since established itself as a leader in oral probiotics health, adding two more patented strains – BLIS M18 for dental health and BLIS Q24 for skin health.
What’s in the white paper
The first study, developed by researchers in Italy, examined the occurrence of Covid-19 in school-aged children. The randomized controlled trial administered a 90-day treatment to 128 participants and found that none of the 64 children consuming BLIS K12 tested positive for Covid-19 compared to the 38% positivity rate in the group not taking the probiotic.
“These results appear to be decidedly consistent with the hypotheses made regarding: 1) the close connection between the oral microbiota and lung microbiota; 2) the possibility that an oral microbiota not dominated by pathogenic or Gram-negative species favors the construction of a lung microbiota less likely to develop inflammatory responses to viruses; and 3) the idea that the administration of orally colonized bacteria belonging to the microbial consortia most frequently found in subjects not affected by Covid-19 is protective against infection,” the study authors wrote.
Meanwhile, a Chinese study in Wuhan used BLIS K12 as supplement in treating recurring recurrent upper respiratory tract infections (RRTi) in children during cold season. The results showed that consumption of BLIS K12 for 30 days, together with conventional treatments, reduced the recurrence rate from 34% to 15%. Children in the treatment group had shorter and more moderate symptoms, reduced absence from school, and less antibiotic and anti-viral treatment.
“Using oropharyngeal probiotics as a complementary treatment to stabilize oropharyngeal microflora, specifically inhibiting respiratory pathogens, could possibly be a promising approach to reduce RRTi burden and combating antibiotic resistance in the long term,” the study authors stated.
In the third study, 193 frontline healthcare workers in China consumed two BLIS K12 lozenges daily for one month to investigate the effect of the probiotic on the prevalence and duration of respiratory infections. Researchers found that it reduced the frequency of respiratory infections by 64.8%, lessened the duration of respiratory tract infections and oral ulcers by 78% and decreased days absent from work by 95.5%.
All three studies invite further research under more controlled conditions.