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Published on: April 28, 2014
Specific probiotics and virological findings in symptomatic conscripts attending military service in Finland
Liisa Lehtoranta1, Kim Kalima2, Liang He3
1Centre for Military Medicine, Research and Development Department, Finnish Defense Forces, FI-00301 Helsinki, Finland; Institute of Biomedicine, Pharmacology, University of Helsinki, FI-00014 Helsinki, Finland.
Insights
Probiotics did not reduce overall respiratory viruses in conscripts. However, they decreased picornaviruses after 3 months, suggesting a potential role against common cold viruses.
Area of Science:
- Microbiology
- Immunology
- Public Health
Background:
- Viral upper respiratory tract infections are common in military conscripts.
- Probiotics have shown efficacy in reducing viral infections in children.
- Limited research exists on probiotics' impact on respiratory viruses in adult populations.
Purpose of the Study:
- To evaluate the effectiveness of probiotics in reducing nasopharyngeal respiratory virus occurrence in Finnish conscripts.
- To investigate the impact of a specific probiotic formulation on viral load.
Main Methods:
- A randomized, double-blind, placebo-controlled study involving 192 symptomatic conscripts.
- Daily administration of a probiotic tablet (Lactobacillus rhamnosus GG and Bifidobacterium animalis ssp. lactis BB-12) or a placebo for 90-150 days.
- Nasopharyngeal swab samples analyzed for respiratory viruses using PCR methods.
Main Results:
- 184 (76.9%) samples tested positive for at least one respiratory virus, with picornaviruses being the most prevalent.
- No significant overall reduction in picornavirus infections was observed between the probiotic and placebo groups (p=0.79).
- A significant decrease in picornavirus detection was noted in the probiotic group after 3 months compared to the control group (p=0.0069).
Conclusions:
- Probiotics did not demonstrate an overall reduction in viral occurrence among symptomatic conscripts.
- A notable decrease in picornaviruses was observed after 3 months of probiotic supplementation.
- Further research is needed to elucidate the mechanisms and target specific probiotics for different respiratory viruses.
Background:
Viral upper respiratory tract infections occur frequently among conscripts. Probiotics have reduced viral infections in children attending day care. Limited data are available on the effects of probiotics on the nasopharyngeal presence of respiratory viruses.
Objectives:
To assess, whether probiotics could decrease nasopharyngeal occurrence of respiratory viruses in Finnish conscripts.
Study Design:
In a randomized, double-blind, placebo-controlled 90- and 150-day intervention study, 239 nasopharyngeal swab samples were collected from 192 symptomatic conscripts receiving daily chewable probiotic tablet containing Lactobacillus rhamnosus GG and Bifidobacterium animalis ssp. lactis BB-12 (46.9%) or control tablet (53.1%) on visits to a garrison's health care center due to symptoms of infection. The presence of respiratory viruses was tested by PCR-methods, and viral findings were compared between the intervention groups.
Results:
184 (76.9%) nasopharyngeal samples were positive for at least one respiratory virus. Picornaviruses were the most common viruses and were detected in 155 (84.2%) of samples. Of these, 143 (92.3%) were rhinovirus-positive and 20 (12.9%) were enterovirus-positive. The control group had 83 (64%) and the probiotic group 72 (66%) picornavirus infections (p=0.79). Monthly distribution of picornaviruses showed that there were less picornavirus findings after 3 months in the probiotic group than in the control group (p=0.0069). However, probiotics did not reduce picornavirus occurrence in other months.
Conclusions:
Overall, probiotics did not reduce viral occurrence in symptomatic conscripts. However, probiotics decreased the presence of picornaviruses after 3 months, which may imply that probiotics play a role against viruses causing common cold. Further investigations are necessary to clarify the mechanisms involved in order to target specific probiotics on specific respiratory viruses.
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