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Probiotics for COVID-19
20 studies from 245 scientists
17,944 patients in 11 countries
Statistically significant improvement for mortality, hospitalization, progression, and recovery.
10 studies from 10 teams in 7 countries show statistically significant improvements.
The immune effects of probiotics are strain-specific.
COVID-19 Probiotics studies. Dec 2022.
0 0.5 1 1.5+ All studies 22% With exclusions 22% Mortality 61% Hospitalization 13% Recovery 16% Cases 31% Viral clearance 4% RCTs 29% RCT mortality 24% Prophylaxis 29% Early 34% Late 17% Favorsprobiotics Favorscontrol
Probiotics COVID-19 studies. The immune effects of probiotics are strain-specific and studies use different strains. Recent:
Neris Almeida Viana
Probiotics have been officially adopted for early treatment in 1 country. Submit updates/corrections.
Dec 2
Covid Analysis (Preprint) (meta analysis) Probiotics for COVID-19: real-time meta analysis of 20 studies
Statistically significant improvements are seen for mortality, hospitalization, progression, and recovery. 10 studies from 10 independent teams in 7 different countries show statistically significant improvements in isolation (5 for the..
Sep 30
Neris Almeida Viana 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.
Aug 24
Navarro-López 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
Rodriguez-Blanque 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
Trinchieri 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
Saviano 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
Zhang 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% lower combined mortality/intubation [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
Santinelli 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
Wischmeyer 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
Wang 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
Bozkurt 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
Leal-Martínez 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
Ivashkin 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
Rathi 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
Ceccarelli 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
Zhang 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
Veterini 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
Wang 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
Meskina 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
Ahanchian 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
Gutiérrez-Castrellón 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
Di Pierro, 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
Holt 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
Haran 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
Kurian 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
Di Pierro 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
Li 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
Singh 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
Shah 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
Ceccarelli 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
Stavropoulou 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
Louca 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
Olaimat 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
d'Ettorre 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
Baud 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.
Hao 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.
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