Probiotics COVID-19 studies. The immune effects of probiotics are strain-specific and studies use different strains.
Recent:Reino-Gelardo.
Probiotics have been officially adopted
in 1 country.
Submit updates/corrections .
Jun 3 |
(Preprint) (meta analysis) | Probiotics for COVID-19: real-time meta analysis of 22 studies |
| Statistically significant improvements are seen for mortality, hospitalization, progression, and recovery. 11 studies from 11 independent teams in 8 different countries show statistically significant improvements in isolation (6 for the.. | ||
Apr 1 |
et al., Nutrients, doi:10.3390/nu15071736 | Effect of an Immune-Boosting, Antioxidant and Anti-Inflammatory Food Supplement in Hospitalized COVID-19 Patients: A Prospective Randomized Pilot Study |
| 61% lower mortality [p=0.05]. RCT 162 late stage (65% on oxygen) patients in Spain, 78 treated with probiotics, prebiotics, vitamin D, zinc, and selenium, showing lower mortality with treatment, statistically significant only within the patients with high severity at .. | ||
Jan 17 |
et al., Nutrients, doi:10.3390/nu15030488 | Ongoing Treatment with a Spore-Based Probiotic Containing Five Strains of Bacillus Improves Outcomes of Mild COVID-19 |
| 40% improved recovery [p=0.008]. Retrospective 60 patients in Romania taking probiotics and 60 matched controls, showing faster symptom resolution with the use of probiotics. Spore-based probiotic containing five strains of Bacillus. | ||
Sep 30 |
et al., Critical Reviews in Food Science and Nutrition, doi:10.1080/10408398.2022.2128713 (meta analysis) | Benefits of probiotic use on COVID-19: A systematic review and meta-analysis |
| 51% improved recovery [p<0.0001]. Systematic review and meta analysis showing significant improvement in symptoms with priobiotic treatment. | ||
Sep 28 |
et al., Microorganisms, doi:10.3390/microorganisms10101926 | Clinical Effects of Streptococcus salivarius K12 in Hospitalized COVID-19 Patients: Results of a Preliminary Study |
| 62% lower mortality [p=0.17] and no change in ICU admission [p=1]. RCT 50 hospitalized patients in Pakistan, 25 treated with S. salivarius K12, showing lower mortality with treatment, without statistical significance. There were more patients with higher oxygen requirements at baseline in the control gro.. | ||
Aug 24 |
et al., Medicine in Microecology, doi:10.1016/j.medmic.2022.100061 | Oral intake of Kluyveromyces marxianus B0399 plus lactobacillus rhamnosus CECT 30579 to mitigate symptoms in COVID-19 patients: A randomized open label clinical trial |
| 33% improved recovery [p=0.08]. RCT with 24 probiotics and 15 control patients in Spain, showing lower overall symptoms and lower digestive symptoms with treatment. Kluyveromyces marxianus B0399 plus lactobacillus rhamnosus CECT 30579. | ||
Aug 3 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2022.962566 | Evaluation of the effect of Loigolactobacillus coryniformis K8 CECT 5711 consumption in health care workers exposed to COVID-19 |
| 9% fewer cases [p=0.92]. Prophylaxis RCT with 127 probiotics and 128 control healthcare workers in Spain, showing no significant difference in cases. There were only 4 cases. Severity information by arm is not provided. L. coryniformis K8 CECT 5711. Treatment may.. | ||
Aug 1 |
et al., Biomedicines, doi:10.3390/biomedicines10081851 | Exploiting Bacteria for Improving Hypoxemia of COVID-19 Patients |
| 78% lower mortality [p=0.28] and 78% improvement [p=0.0001]. Retrospective COVID-19 patients requiring CPAP, 21 treated with SLAB51 probiotics and 15 control patients, showing improved outcomes with treatment, despite significantly lower blood oxygenation at baseline in the treatment group. | ||
Jun 28 |
et al., Journal of Clinical Medicine, doi:10.3390/jcm11133758 | COVID-19 Pneumonia and Gut Inflammation: The Role of a Mix of Three Probiotic Strains in Reducing Inflammatory Markers and Need for Oxygen Support |
| 86% lower ICU admission [p=0.24] and 26% shorter hospitalization [p=0.52]. RCT 80 COVID-19 interstitial pneumonia patients in Italy, 40 treated with probiotics, showing significantly reduced gut inflammatory markers with treatment, and lower ICU admission and mortality, without statistical significance. Bifidoba.. | ||
Mar 2 |
et al., Journal of Gastroenterology and Hepatology, doi:10.1111/jgh.15796 | Gut microbiota-derived synbiotic formula (SIM01) as a novel adjuvant therapy for COVID-19: An open-label pilot study |
| 67% improvement [p=0.06]. Pilot study of probiotic SIM01 with 25 consecutive COVID-19 patients in Hong Kong and 30 control patients treated by a different team during the same time period, showing improved antibody formation, reduced viral load and pro-inflammator.. | ||
Jan 12 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2021.756177 | Oral Bacteriotherapy Reduces the Occurrence of Chronic Fatigue in COVID-19 Patients |
| 54% improved recovery [p<0.0001]. Retrospective 58 hospitalized patients, 24 receiving probiotics during hospitalization, showing significantly lower fatigue six months post discharge with treatment. | ||
Jan 5 |
et al., medRxiv, doi:10.1101/2022.01.04.21268275 (Preprint) | Daily Lactobacillus Probiotic versus Placebo in COVID-19-Exposed Household Contacts (PROTECT-EHC): A Randomized Clinical Trial |
| 33% fewer moderate/severe cases [p=0.15], 38% fewer symptomatic cases [p=0.02], 27% faster recovery [p=0.37], and 43% fewer cases [p=0.17]. RCT 182 COVID-19 exposed patients, 91 treated with daily probiotic Lactobacillus rhamnosus GG starting a median of 3 days from exposure, showing lower symptomatic COVID-19 with treatment. There were no hospitalizations or deaths. | ||
Dec 31 2021 |
et al., Annals of Palliative Medicine, doi:10.21037/apm-21-3373 | The efficacy of probiotics in patients with severe COVID-19 |
| Retrospective 156 COVID-19 patients in China, showing that diarrhea was significantly more common in severe/critical cases, and for severe/critical patients experiencing diarrhea, the duration of diarrhea was shorter with probiotic treatm.. | ||
Nov 25 2021 |
et al., International Journal of Immunopathology and Pharmacology, doi:10.1177/20587384211059677 | Oral booster probiotic bifidobacteria in SARS-COV-2 patients |
| Small retrospective 44 hospitalized patients in Turkey, showing improved outcomes with probiotic bifidobacterium, however minimal group details are provided (for example, the age of the control patients is unknown), and no adjustments wer.. | ||
Oct 25 2021 |
et al., International Journal of Environmental Research and Public Health, doi:10.3390/ijerph19031172 (date from earlier preprint) | Effect of a Nutritional Support System to Increase Survival and Reduce Mortality in Patients with COVID-19 in Stage III and Comorbidities: A Blinded Randomized Controlled Clinical Trial |
| 86% lower mortality [p=0.03] and 57% lower ventilation [p=0.31]. 80 patient RCT with 40 patients treated with a comprehensive regimen of nutritional support, showing significantly lower mortality with treatment. Treatment contained cholecalciferol, vitamin C, zinc, spirulina maxima, folic acid, glutami.. | ||
Oct 13 2021 |
et al., Probiotics Antimicrob Proteins, doi:10.1007/s12602-021-09858-5 | Efficacy of a Probiotic Consisting of Lacticaseibacillus rhamnosus PDV 1705, Bifidobacterium bifidum PDV 0903, Bifidobacterium longum subsp. infantis PDV 1911, and Bifidobacterium longum subsp. longum PDV 2301 in the Treatment of Hospitalized Patients with COVID-19: a Randomized Controlled Trial |
| 2% higher mortality [p=1], 18% lower ventilation [p=1], 27% lower ICU admission [p=0.77], and 5% faster recovery [p=0.47]. RCT 200 patients, 99 treated with a probiotic (Lacticaseibacillus rhamnosus PDV 1705, Bifidobacterium bifidum PDV 0903, Bifidobacterium longum subsp. infantis PDV 1911, and Bifidobacterium longum subsp. longum PDV 2301). There was no sign.. | ||
Aug 30 2021 |
et al., Medicines, doi:10.3390/medicines8090047 | A Randomized Controlled Trial of the Efficacy of Systemic Enzymes and Probiotics in the Resolution of Post-COVID Fatigue |
| 89% improved recovery [p<0.0001]. RCT 200 long-COVID patients in India, 100 treated with ImmunoSEB and ProbioSEB CSC3, showing improved recovery of post-COVID-19 fatigue with treatment. CTRI/2021/05/033576. | ||
Aug 23 2021 |
et al., Nutrients, doi:10.3390/nu13082898 | Oxygen Sparing Effect of Bacteriotherapy in COVID-19 |
| 82% lower ICU admission [p=0.15]. Prospective analysis of 69 severe COVID-19 patients requiring non-invasive oxygen therapy, 40 treated with probiotic formulation SLAB51, showing lower oxygen requirements and higher blood levels of pO2, O2Hb and SaO2 with treatment. Autho.. | ||
Aug 4 2021 |
et al., Therapeutic Advances in Gastroenterology, doi:10.1177/17562848211035670 | Probiotics use is associated with improved clinical outcomes among hospitalized patients with COVID-19 |
| 14% shorter hospitalization [p=0.009], 14% faster recovery [p=0.02], and 17% faster viral clearance [p=0.001]. Retrospective 375 patients in China, 179 treated with probiotics (Bifidobacterium, Lactobacillus, and Enterococcus), showing improved clinical outcomes with treatment. | ||
Jun 30 2021 |
et al., Indian Journal of Forensic Medicine & Toxicology, 15:2 | Probiotics Intake as Adjunct Therapy for Infected Health-Care with SARS COV-2 |
| 29% faster viral clearance [p=0.22]. Small case control analysis with 15 probiotics patients and 15 contol patients, showing no significant differences. PCR tests were only done weekly. Dosage is unknown. 115/LOE/301.4.2/IX/2020. | ||
Jun 24 2021 |
et al., Front. Bioeng. Biotechnol., doi:10.3389/fbioe.2021.646184 | Oropharyngeal Probiotic ENT-K12 Prevents Respiratory Tract Infections Among Frontline Medical Staff Fighting Against COVID-19: A Pilot Study |
| Prophylaxis RCT in China with 98 healthcare workes in close contact with COVID-19 patients treated with Bactoblis oropharyngeal probiotic containing S. thermophilus ENT-K12, and 95 control patients, showing lower incidence of respiratory .. | ||
Jun 1 2021 |
et al., Therapeutic Archive, doi:10.26442/00403660.2021.04.200835 | Efficiency of application of sorbed probiotics in complex therapy of pneumonia caused by SARS-CoV-2 |
| RCT 100 pneumonia patients in Russia, showing faster symptom resolution with probiotic treatment (B. bifidum 1). | ||
May 31 2021 |
et al., Open Journal of Nursing, doi:10.4236/ojn.2021.115025 | Synbiotic for Prevention of SARS-Cov2 Infection in High Risk Hospital Staffs: A Randomized Controlled Trial |
| 73% fewer symptomatic cases [p=0.35] and 85% fewer cases [p=0.24]. Small RCT 60 healthcare workers in Iran, showing lower cases with treatment but without statistical significance. Once daily oral synbiotic capsule (Lactocare®) containing 1 billion CFU L. (Lactobacillus) casei, L. rhamnosus, Streptococcu.. | ||
May 24 2021 |
et al., Gut Microbes, doi:10.1080/19490976.2021.2018899 (date from earlier preprint) | Probiotic improves symptomatic and viral clearance in Covid19 outpatients: a randomized, quadruple-blinded, placebo-controlled trial |
| 35% improved recovery [p<0.0001]. RCT 293 outpatients in Mexico, 147 treated with a probiotic composed of three L. plantarum strains (KABP022, KABP023 and KABP033) and one P. acidilacti strain (KABP021), showing improved recovery with treatment. There were no hospitalizat.. | ||
Apr 7 2021 |
, F., Minerva Medica, doi:10.23736/S0026-4806.20.06570-2 (Review) | A possible probiotic (S. salivarius K12) approach to improve oral and lung microbiotas and raise defenses against SARS-CoV-2 |
| Review of the potential use of S. salivarius K12 for COVID-19. Author notes that strain K12 of streptococcus salivarius may reduce occurrence of viral upper respiratory tract infections, possibly due to its ability to stimulate IFN-γ rele.. | ||
Mar 30 2021 |
et al., Thorax, doi:10.1136/thoraxjnl-2021-217487 | Risk factors for developing COVID-19: a population-based longitudinal study (COVIDENCE UK) |
| 30% fewer cases [p=0.11]. Prospective survey-based study with 15,227 people in the UK, showing lower risk of COVID-19 cases with vitamin A, vitamin D, zinc, selenium, probiotics, and inhaled corticosteroids; and higher risk with metformin and vitamin C. Statistica.. | ||
Mar 29 2021 |
et al., medRxiv, doi:10.1101/2021.03.26.21254422 (Preprint) | Targeting the Microbiome With KB109 in Outpatients with Mild to Moderate COVID-19 Reduced Medically Attended Acute Care Visits and Improved Symptom Duration in Patients With Comorbidities |
| 50% fewer combined hospitalization/ER visits [p=0.13] and 20% faster recovery [p=0.1]. RCT 350 COVID+ outpatients in the USA, 174 treated with prebiotic KB109 (a microbiome metabolic therapy candidate), showing lower combined hospitalization, ER, and urgent care visits with treatment. NCT04414124. | ||
Mar 19 2021 |
et al., Archives of Medical Research, doi:10.1016/j.arcmed.2021.03.002 (Review) | Probiotics in Prevention and Treatment of COVID-19: Current Perspective and Future Prospects |
| Review of probiotics role in regulating the immune system and use in viral infections, and studies on the association of microbiota with COVID-19 patients. Authors suggest that probiotics supplementation could reduce COVID-19 morbidity an.. | ||
Mar 12 2021 |
et al., Minerva Medica, doi:10.23736/S0026-4806.21.07487-5 | The administration of S. salivarius K12 to children may reduce the rate of SARS-CoV-2 infection |
| 98% fewer cases [p<0.0001]. Interim report on an RCT for prophylactic treatment with S. salivarius K12, showing significantly lower cases with treatment. Only patients with symptoms or known positive contacts were tested. Trial identification/registration details ar.. | ||
Mar 5 2021 |
et al., International Immunopharmacology, doi:10.1016/j.intimp.2021.107531 | The role of probiotics in coronavirus disease-19 infection in Wuhan: A retrospective study of 311 severe patients |
| 12% lower hospital discharge [p=0.68] and 35% slower viral clearance [p=0.001]. Retrospective 311 severe condition hospitalized patients in China, 123 treated with probiotics, showing slower viral clearance and recovery with treatment. Authors note that probiotics were able to moderate immunity and decrease the incid.. | ||
Feb 13 2021 |
et al., Nutrition Research, doi:10.1016/j.nutres.2020.12.014 (Review) | Probiotics: A potential immunomodulator in COVID-19 infection management |
| Review of studies supporting the use of probiotics for respiratory infections and identification of microbial strains potentially beneficial for COVID-19. | ||
Feb 2 2021 |
et al., Advances in Clinical Toxicology, doi:10.23880/act-16000204 | Potential of the Combination of a Systemic Enzyme Complex and Probiotics administration to Combat COVID-19: A Randomized Open Label Prospective Analysis |
| 11% faster recovery [p=0.19] and 11% shorter hospitalization [p=0.18]. Small RCT 60 patients in India, 30 treated with ImmunoSEB and ProbioSEB CSC3, showing faster recovery with treatment. CTRI/2020/09/027685, CTRI/2020/08/027168. | ||
Jan 11 2021 |
et al., Frontiers in Medicine, doi:10.3389/fnut.2020.613928 | Oral Bacteriotherapy in Patients With COVID-19: A Retrospective Cohort Study |
| 64% lower mortality [p=0.003] and 15% lower ICU admission [p=0.6]. Retrospective 200 severe condition hospitalized patients in Italy, 88 treated with probiotic Sivomixx, showing lower mortality with treatment. | ||
Dec 15 2020 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2020.614986 (Review) | Probiotics as a Weapon in the Fight Against COVID-19 |
| Review of the potential benefits of probiotics for COVID-19. | ||
Nov 30 2020 |
et al., BMJ Nutrition, Prevention & Health, doi:10.1136/bmjnph-2021-000250 (date from earlier preprint) | Modest effects of dietary supplements during the COVID-19 pandemic: insights from 445 850 users of the COVID-19 Symptom Study app |
| 8% fewer cases [p=0.03]. Survey analysis of dietary supplements showing probiotic usage associated with lower incidence of COVID-19. These results are for PCR+ cases only, they do not reflect potential benefits for reducing the severity of cases. A number of bias.. | ||
Oct 5 2020 |
et al., npj Science of Food, doi:10.1038/s41538-020-00078-9 (Review) | The potential application of probiotics and prebiotics for the prevention and treatment of COVID-19 |
| Review of the immune benefits of probiotics and clinical studies for the preventation and treatment of respiratory infections, recommending trials of probiotics for COVID-19. | ||
Jul 7 2020 |
et al., Frontiers in Medicine, doi:10.3389/fmed.2020.00389 | Challenges in the Management of SARS-CoV2 Infection: The Role of Oral Bacteriotherapy as Complementary Therapeutic Strategy to Avoid the Progression of COVID-19 |
| 87% lower mortality [p=0.14] and 88% lower progression [p=0.01]. Retrospective 70 hospitalized patients in Italy, 28 treated with probiotic Sivomixx, showing lower risk of respiratory failure and faster recovery with treatment. | ||
May 8 2020 |
et al., Frontiers in Public Health, doi:10.3389/fpubh.2020.00186 (Review) | Using Probiotics to Flatten the Curve of Coronavirus Disease COVID-2019 Pandemic |
| Review of data supporting the use of probiotics for COVID-19 and mechanisms of action. | ||
Feb 3 2015 |
et al., Cochrane Database of Systematic Reviews, doi:10.1002/14651858.CD006895.pub3 (Preprint) (meta analysis) | Probiotics for preventing acute upper respiratory tract infections |
| Meta analysis of 12 RCTs with 3,720 patients showing probiotics reduced acute upper respiratory tract infections. | ||
Please send us corrections, updates, or comments. Vaccines and
treatments are complementary. All practical, effective, and safe means should
be used based on risk/benefit analysis. No treatment, vaccine, or intervention
is 100% available and effective for all current and future variants. We do not
provide medical advice. Before taking any medication, consult a qualified
physician who can provide personalized advice and details of risks and
benefits based on your medical history and situation. FLCCC and WCH
provide treatment protocols.
Thanks for your feedback! Please search before submitting papers and note
that studies are listed under the date they were first available, which may be
the date of an earlier preprint.