Alterations in the respiratory tract microbiome in COVID-19: current observations and potential significance

Carter Merenstein, Frederic D Bushman, Ronald G Collman, Carter Merenstein, Frederic D Bushman, Ronald G Collman

Abstract

SARS-CoV-2 infection causes COVID-19 disease, which can result in consequences ranging from undetectable to fatal, focusing attention on the modulators of outcomes. The respiratory tract microbiome is thought to modulate the outcomes of infections such as influenza as well as acute lung injury, raising the question to what degree does the airway microbiome influence COVID-19? Here, we review the results of 56 studies examining COVID-19 and the respiratory tract microbiome, summarize the main generalizations, and point to useful avenues for further research. Although the results vary among studies, a few consistent findings stand out. The diversity of bacterial communities in the oropharynx typically declined with increasing disease severity. The relative abundance of Haemophilus and Neisseria also declined with severity. Multiple microbiome measures tracked with measures of systemic immune responses and COVID outcomes. For many of the conclusions drawn in these studies, the direction of causality is unknown-did an alteration in the microbiome result in increased COVID severity, did COVID severity alter the microbiome, or was some third factor the primary driver, such as medication use. Follow-up mechanistic studies can help answer these questions. Video Abstract.

Conflict of interest statement

The authors declare that they have no competing interests.

© 2022. The Author(s).

Figures

Fig. 1
Fig. 1
Associations of oropharyngeal microbiome features with COVID-19 relative to healthy controls. Analytical approaches and statistical methods varied among studies; results tabulated reflect the authors’ conclusions. Only studies that collected both COVID-19 and healthy controls are included; studies employing samples for either group from public data exclusively were not included. The sample size reports the number of COVID-19 patients and healthy controls. The results were filtered to emphasize findings consistent across more than one study
Fig. 2
Fig. 2
Associations between oropharyngeal microbiome features and COVID-19 severity. Analytical approaches and statistical methods varied among studies; results tabulated reflect the authors’ conclusions. Disease severity comparisons varied and included asymptomatic vs symptomatic, moderate vs severe, alive vs dead, and others. The sample size refers to the number of COVID-19 patients only
Fig. 3
Fig. 3
Associations of nasopharyngeal microbiome features with COVID-19, relative to healthy controls. Only studies that collected both COVID-19 and healthy controls are included; studies pulling samples for either group from public data exclusively were left out. The sample size reports the number of COVID-19 patients and healthy controls. The results were filtered to emphasize findings consistent across more than one study
Fig. 4
Fig. 4
Associations between nasopharyngeal microbiome features and COVID-19 severity. Disease severity was defined differently across studies, ranging from asymptomatic vs symptomatic, to recovered vs deceased. Analytical approaches and statistical methods varied among studies; results tabulated reflect the authors’ conclusions. Disease severity comparisons varied, and included asymptomatic vs symptomatic, moderate vs severe, alive vs dead, and others. The sample size includes COVID-19 patients only

References

    1. Li L, et al. COVID-19 patients’ clinical characteristics, discharge rate, and fatality rate of meta-analysis. J Med Virol. 2020;92:577–583. doi: 10.1002/jmv.25757.
    1. Izcovich A, et al. Prognostic factors for severity and mortality in patients infected with COVID-19: a systematic review. PLoS One. 2020;15:e0241955. doi: 10.1371/journal.pone.0241955.
    1. Gallo Marin B, et al. Predictors of COVID-19 severity: a literature review. Rev Med Virol. 2021;31:e2146. doi: 10.1002/rmv.2146.
    1. Cui L, et al. The microbiome and the lung. Ann Am Thorac Soc. 2014;11:S227–S232. doi: 10.1513/AnnalsATS.201402-052PL.
    1. Whiteside SA, McGinniss JE, Collman RG. The lung microbiome: progress and promise. J Clin Invest. 2021;131(15):e150473. doi: 10.1172/JCI150473.
    1. Charlson ES, et al. Topographical continuity of bacterial populations in the healthy human respiratory tract. Am J Respir Crit Care Med. 2011;184:957–963. doi: 10.1164/rccm.201104-0655OC.
    1. Morris A, et al. Comparison of the respiratory microbiome in healthy nonsmokers and smokers. Am J Respir Crit Care Med. 2013;187:1067–1075. doi: 10.1164/rccm.201210-1913OC.
    1. Charlson ES, et al. Disordered microbial communities in the upper respiratory tract of cigarette smokers. PLoS One. 2010;5:e15216. doi: 10.1371/journal.pone.0015216.
    1. Simon-Soro A, et al. Upper respiratory dysbiosis with a facultative-dominated ecotype in advanced lung disease and dynamic change after lung transplant. Ann Am Thorac Soc. 2019;16:1383–1391. doi: 10.1513/AnnalsATS.201904-299OC.
    1. Beck JM, et al. Multicenter comparison of lung and oral microbiomes of HIV-infected and HIV-uninfected individuals. Am J Respir Crit Care Med. 2015;192:1335–1344. doi: 10.1164/rccm.201501-0128OC.
    1. Rhee RL, et al. Characterisation of the nasal microbiota in granulomatosis with polyangiitis. Ann Rheum Dis. 2018;77:1448–1453. doi: 10.1136/annrheumdis-2018-213645.
    1. Kaul D, et al. Microbiome disturbance and resilience dynamics of the upper respiratory tract during influenza A virus infection. Nat Commun. 2020;11:2537. doi: 10.1038/s41467-020-16429-9.
    1. Huang YJ. The respiratory microbiome and innate immunity in asthma. Curr Opin Pulm Med. 2015;21:27–32. doi: 10.1097/MCP.0000000000000124.
    1. Surette MG. The cystic fibrosis lung microbiome. Ann Am Thorac Soc. 2014;11:S61–S65. doi: 10.1513/AnnalsATS.201306-159MG.
    1. Pragman AA, Kim HB, Reilly CS, Wendt C, Isaacson RE. The lung microbiome in moderate and severe chronic obstructive pulmonary disease. PLoS One. 2012;7:e47305. doi: 10.1371/journal.pone.0047305.
    1. Twigg HL, et al. Effect of advanced HIV infection on the respiratory microbiome. Am J Respir Crit Care Med. 2016;194:226–235. doi: 10.1164/rccm.201509-1875OC.
    1. Fromentin M, Ricard J-D, Roux D. Respiratory microbiome in mechanically ventilated patients: a narrative review. Intensive Care Med. 2021;47:292–306. doi: 10.1007/s00134-020-06338-2.
    1. Lee KH, et al. The respiratory microbiome and susceptibility to influenza virus infection. PLoS One. 2019;14:e0207898. doi: 10.1371/journal.pone.0207898.
    1. Tsang TK, et al. Association between the respiratory microbiome and susceptibility to influenza virus infection. Clin Infect Dis. 2020;71:1195–1203. doi: 10.1093/cid/ciz968.
    1. Huffnagle GB, Dickson RP, Lukacs NW. The respiratory tract microbiome and lung inflammation: a two-way street. Mucosal Immunol. 2017;10:299–306. doi: 10.1038/mi.2016.108.
    1. Invernizzi R, Lloyd CM, Molyneaux PL. Respiratory microbiome and epithelial interactions shape immunity in the lungs. Immunology. 2020;160:171–182. doi: 10.1111/imm.13195.
    1. Segal LN, et al. Enrichment of lung microbiome with supraglottic taxa is associated with increased pulmonary inflammation. Microbiome. 2013;1:19. doi: 10.1186/2049-2618-1-19.
    1. Segal LN, et al. Enrichment of the lung microbiome with oral taxa is associated with lung inflammation of a Th17 phenotype. Nat Microbiol. 2016;1:16031. doi: 10.1038/nmicrobiol.2016.31.
    1. Li K, et al. Dysbiosis of lower respiratory tract microbiome are associated with inflammation and microbial function variety. Respir Res. 2019;20:272. doi: 10.1186/s12931-019-1246-0.
    1. Dickson RP, et al. Enrichment of the lung microbiome with gut bacteria in sepsis and the acute respiratory distress syndrome. Nat Microbiol. 2016;1:1–9. doi: 10.1038/nmicrobiol.2016.113.
    1. Dickson RP, et al. Lung microbiota predict clinical outcomes in critically ill patients. Am J Respir Crit Care Med. 2020;201:555–563. doi: 10.1164/rccm.201907-1487OC.
    1. Panzer AR, et al. Lung microbiota is related to smoking status and to development of acute respiratory distress syndrome in critically ill trauma patients. Am J Respir Crit Care Med. 2018;197:621–631. doi: 10.1164/rccm.201702-0441OC.
    1. García LF. Immune response, inflammation, and the clinical spectrum of COVID-19. Front Immunol. 2020;11:1441. doi: 10.3389/fimmu.2020.01441.
    1. Ramasamy S, Subbian S. Critical determinants of cytokine storm and type I interferon response in COVID-19 pathogenesis. Clin Microbiol Rev. 2021;34:e00299–e00220.
    1. Yamamoto S, et al. The human microbiome and COVID-19: a systematic review. PLoS One. 2021;16:e0253293. doi: 10.1371/journal.pone.0253293.
    1. Segal JP, et al. The gut microbiome: an under-recognised contributor to the COVID-19 pandemic? Ther Adv Gastroenterol. 2020;13:1756284820974914. doi: 10.1177/1756284820974914.
    1. Najmi N, Megantara I, Andriani L, Goenawan H, Lesmana R. Importance of gut microbiome regulation for the prevention and recovery process after SARS-CoV-2 respiratory viral infection (Review) Biomed Rep. 2022;16:25. doi: 10.3892/br.2022.1508.
    1. Vallianou NG, Stratigou T, Tsagarakis S. Microbiome and diabetes: where are we now? Diabetes Res Clin Pract. 2018;146:111–118. doi: 10.1016/j.diabres.2018.10.008.
    1. Singer-Englar T, Barlow G, Mathur R. Obesity, diabetes, and the gut microbiome: an updated review. Expert Rev Gastroenterol Hepatol. 2019;13:3–15. doi: 10.1080/17474124.2019.1543023.
    1. Castaner O, et al. The gut microbiome profile in obesity: a systematic review. Int J Endocrinol. 2018;2018:e4095789.
    1. Dang AT, Marsland BJ. Microbes, metabolites, and the gut–lung axis. Mucosal Immunol. 2019;12:843–850. doi: 10.1038/s41385-019-0160-6.
    1. Dickson RP, et al. The lung microbiota of healthy mice are highly variable, cluster by environment, and reflect variation in baseline lung innate immunity. Am J Respir Crit Care Med. 2018;198:497–508. doi: 10.1164/rccm.201711-2180OC.
    1. Gao M, et al. Characterization of the human oropharyngeal microbiomes in SARS-CoV-2 infection and recovery patients. Adv Sci. 2021;8:2102785. doi: 10.1002/advs.202102785.
    1. Rosas-Salazar C, et al. SARS-CoV-2 infection and viral load are associated with the upper respiratory tract microbiome. J Allergy Clin Immunol. 2021;147:1226–1233.e2. doi: 10.1016/j.jaci.2021.02.001.
    1. de Castilhos J, et al. Severe dysbiosis and specific Haemophilus and Neisseria signatures as hallmarks of the oropharyngeal microbiome in critically ill COVID-19 patients. Clin Infect Dis. 2021;25:ciab902. .
    1. Xu R, et al. Progressive deterioration of the upper respiratory tract and the gut microbiomes in children during the early infection stages of COVID-19. J Genet Genomics. 2021;48:803–814. doi: 10.1016/j.jgg.2021.05.004.
    1. Hernández-Terán A, et al. Dysbiosis and structural disruption of the respiratory microbiota in COVID-19 patients with severe and fatal outcomes. Sci Rep. 2021;11:21297. doi: 10.1038/s41598-021-00851-0.
    1. Caverly LJ, Huang YJ, Sze MA. Past, present, and future research on the lung microbiome in inflammatory airwaydisease. Chest. 2019;156:376–382. doi: 10.1016/j.chest.2019.05.011.
    1. Ma S, et al. Metagenomic analysis reveals oropharyngeal microbiota alterations in patients with COVID-19. Signal Transduct Target Ther. 2021;6:1–11. doi: 10.1038/s41392-021-00614-3.
    1. Ren L, et al. Dynamics of the upper respiratory tract microbiota and its association with mortality in COVID-19. Am J Respir Crit Care Med. 2021;204:1379–1390. doi: 10.1164/rccm.202103-0814OC.
    1. Li J, et al. Assessment of microbiota in the gut and upper respiratory tract associated with SARS-CoV-2 infection. SSRN (preprint). 2020. Preprint at 10.2139/ssrn.3702488.
    1. Rueca M, et al. Investigation of nasal/oropharyngeal microbial community of COVID-19 patients by 16S rDNA sequencing. Int J Environ Res Public Health. 2021;18:2174. doi: 10.3390/ijerph18042174.
    1. Lloréns-Rico V, et al. Clinical practices underlie COVID-19 patient respiratory microbiome composition and its interactions with the host. medRxiv (preprint). 2021: 2020.12.23.20248425. Preprint at 10.1101/2020.12.23.20248425.
    1. Bradley ES, et al. Oropharyngeal microbiome profiled at admission is predictive of the need for respiratory support among COVID-19 patients. medRxiv (preprint). 2022: 2022.02.28.22271627 Preprint at 10.1101/2022.02.28.22271627.
    1. Braun T, et al. SARS-CoV-2 does not have a strong effect on the nasopharyngeal microbial composition. Sci Rep. 2021;11:8922. doi: 10.1038/s41598-021-88536-6.
    1. Mostafa HH, et al. Metagenomic next-generation sequencing of nasopharyngeal specimens collected from confirmed and suspect COVID-19 patients. mBio. 2020;11:e01969–e01920. doi: 10.1128/mBio.01969-20.
    1. Hurst JH, et al. Age-related changes in the upper respiratory microbiome are associated with SARS-CoV-2 susceptibility and illness severity. medRxiv (preprint). 2021:2021.03.20.21252680 Preprint at 10.1101/2021.03.20.21252680.
    1. Kullberg RFJ, et al. Lung microbiota of critically ill COVID-19 patients are associated with non-resolving acute respiratory distress syndrome. Am J Respir Crit Care Med. 2022. 10.1164/rccm.202202-0274OC.
    1. Gupta A, et al. Nasopharyngeal microbiome reveals the prevalence of opportunistic pathogens in SARS-CoV-2 infected individuals and their association with host types. Microbes Infect. 2022;24:104880. doi: 10.1016/j.micinf.2021.104880.
    1. Shilts MH, et al. Severe COVID-19 is associated with an altered upper respiratory tract microbiome. Front Cell Infect Microbiol. 2022;11:781968. doi: 10.3389/fcimb.2021.781968.
    1. Gupta VK, et al. A predictive index for health status using species-level gut microbiome profiling. Nat Commun. 2020;11:4635. doi: 10.1038/s41467-020-18476-8.
    1. Kolhe R, et al. Alteration in nasopharyngeal microbiota profile in aged patients with COVID-19. Diagnostics. 2021;11:1622. doi: 10.3390/diagnostics11091622.
    1. Feehan AK, et al. Nasopharyngeal microbiome community composition and structure is associated with severity of COVID-19 disease and breathing treatment. Appl Microbiol. 2021;1:177–188. doi: 10.3390/applmicrobiol1020014.
    1. Babenko V, et al. Analysis of the upper respiratory tract microbiota in mild and severe COVID-19 patients. bioRxiv (preprint). 2021: 2021.09.20.461025 Preprint at 10.1101/2021.09.20.461025.
    1. Ventero MP, et al. Nasopharyngeal microbial communities of patients infected with SARS-CoV-2 that developed COVID-19. Front Microbiol. 2021;12:637430. doi: 10.3389/fmicb.2021.637430.
    1. Mahapatra S, et al. Nanopore 16S rRNA sequencing reveals alterations in nasopharyngeal microbiome and enrichment of Mycobacterium and Mycoplasma in patients with COVID 19. medRxiv (preprint). 2021: 2021.11.10.21266147. Preprint at 10.1101/2021.11.10.21266147.
    1. Nagy-Szakal D, et al. Targeted hybridization capture of SARS-CoV-2 and metagenomics enables genetic variant discovery and nasal microbiome insights. Microbiol Spectr. 9:e00197–21.
    1. Rhoades NS, et al. Acute SARS-CoV-2 infection is associated with an increased abundance of bacterial pathogens, including Pseudomonas aeruginosa in the nose. Cell Rep. 2021;36:109637. doi: 10.1016/j.celrep.2021.109637.
    1. Merenstein C, et al. Signatures of COVID-19 severity and immune response in the respiratory tract microbiome. mBio. 2021;12:e0177721. doi: 10.1128/mBio.01777-21.
    1. Chen J, et al. Comparison of the respiratory tractmicrobiome in hospitalized COVID-19 patients with different disease severity. ResearchSquare (preprint). 2022. Preprint at 10.21203/-1237564/v1.
    1. Kelly BJ, et al. Composition and dynamics of the respiratory tract microbiome in intubated patients. Microbiome. 2016;4:7. doi: 10.1186/s40168-016-0151-8.
    1. Zakharkina T, et al. The dynamics of the pulmonary microbiome during mechanical ventilation in the intensive care unit and the association with occurrence of pneumonia. Thorax. 2017;72:803–810. doi: 10.1136/thoraxjnl-2016-209158.
    1. Tsitsiklis A, et al. Impaired immune signaling and changes in the lung microbiome precede secondary bacterial pneumonia in COVID-19. medRxiv (preprint). 2021: 2021.03.23.21253487 Preprint at 10.1101/2021.03.23.21253487.
    1. Sulaiman I, et al. Microbial signatures in the lower airways of mechanically ventilated COVID-19 patients associated with poor clinical outcome. Nat Microbiol. 2021;6:1245–1258. doi: 10.1038/s41564-021-00961-5.
    1. Gaibani P, et al. The lower respiratory tract microbiome of critically ill patients with COVID-19. Sci Rep. 2021;11:10103. doi: 10.1038/s41598-021-89516-6.
    1. Viciani E, et al. Critically ill patients with COVID-19 show lung fungal dysbiosis with reduced microbial diversity in patients colonized with Candida spp. Int J Infect Dis. 2022;117:233–240. doi: 10.1016/j.ijid.2022.02.011.
    1. Zacharias M, et al. Host and microbiome features of secondary infections in lethal covid-19. medRxiv (preprint). 2022: 2022.02.18.22270995. Preprint at 10.1101/2022.02.18.22270995.
    1. Langford BJ, et al. Bacterial co-infection and secondary infection in patients with COVID-19: a living rapid review and meta-analysis. Clin Microbiol Infect. 2020;26:1622–1629. doi: 10.1016/j.cmi.2020.07.016.
    1. Morris DE, Cleary DW, Clarke SC. Secondary bacterial infections associated with influenza pandemics. Front Microbiol. 2017;8:1041. doi: 10.3389/fmicb.2017.01041.
    1. Klein EY, et al. The frequency of influenza and bacterial coinfection: a systematic review and meta-analysis. Influenza Other Respir Viruses. 2016;10:394–403. doi: 10.1111/irv.12398.
    1. Petruk G, et al. SARS-CoV-2 spike protein binds to bacterial lipopolysaccharide and boosts proinflammatory activity. J Mol Cell Biol. 2020;12:916–932. doi: 10.1093/jmcb/mjaa067.
    1. Kruglikov IL, Scherer PE. Preexisting and inducible endotoxemia as crucial contributors to the severity of COVID-19 outcomes. PLoS Pathog. 2021;17:e1009306. doi: 10.1371/journal.ppat.1009306.
    1. Hoenigl M, et al. The emergence of COVID-19 associated mucormycosis: a review of cases from 18 countries. Lancet Microbe. 2022. 10.1016/S2666-5247(21)00237-8.
    1. Gangneux J-P, et al. Fungal infections in mechanically ventilated patients with COVID-19 during the first wave: the French multicentre MYCOVID study. Lancet Respir Med. 2022;10:180–190. doi: 10.1016/S2213-2600(21)00442-2.
    1. Prattes J, et al. Risk factors and outcome of pulmonary aspergillosis in critically ill coronavirus disease 2019 patients-a multinational observational study by the European Confederation of Medical Mycology. Clin Microbiol Infect Off Publ Eur Soc Clin Microbiol Infect Dis. 2022;28:580–587.
    1. Verweij PE, et al. Taskforce report on the diagnosis and clinical management of COVID-19 associated pulmonary aspergillosis. Intensive Care Med. 2021;47:819–834. doi: 10.1007/s00134-021-06449-4.
    1. Song G, Liang G, Liu W. Fungal co-infections associated with global COVID-19 pandemic: a clinical and diagnostic perspective from China. Mycopathologia. 2020;185:599–606. doi: 10.1007/s11046-020-00462-9.
    1. Musuuza JS, et al. Prevalence and outcomes of co-infection and superinfection with SARS-CoV-2 and other pathogens: a systematic review and meta-analysis. PLoS One. 2021;16:e0251170. doi: 10.1371/journal.pone.0251170.
    1. Hoque MN, et al. Metagenomic analysis reveals the abundance and diversity of opportunistic fungal pathogens in the nasopharyngeal tract of COVID-19 patients. 2022: 2022.02.17.480819 Preprint at 10.1101/2022.02.17.480819.
    1. Danion F, et al. Coronavirus disease 2019-associated mucormycosis in France: a rare but deadly complication. Open Forum Infect Dis. 2022;9:ofab566. doi: 10.1093/ofid/ofab566.
    1. Miao Q, et al. Evaluation of superinfection, antimicrobial usage, and airway microbiome with metagenomic sequencing in COVID-19 patients: a cohort study in Shanghai. J Microbiol Immunol Infect. 2021;54:808–815. doi: 10.1016/j.jmii.2021.03.015.
    1. Temerozo JR, et al. Human endogenous retrovirus K in the respiratory tract is associated with COVID-19 physiopathology. Microbiome. 2022;10:65. doi: 10.1186/s40168-022-01260-9.
    1. Chan AS, Rout A. Use of neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios in COVID-19. J Clin Med Res. 2020;12:448–453. doi: 10.14740/jocmr4240.
    1. Jimeno S, et al. Prognostic implications of neutrophil-lymphocyte ratio in COVID-19. Eur J Clin Invest. 2021;51:e13404. doi: 10.1111/eci.13404.
    1. Hursitoglu M, et al. In-vitro cytokine production and nasopharyngeal microbiota composition in the early stage of COVID-19 infection. Cytokine. 2022;149:155757. doi: 10.1016/j.cyto.2021.155757.
    1. Cuthbertson L, et al. Resilience of the respiratory microbiome in controlled adult RSV challenge study. Eur Respir J. 2022;59(1):2101932. 10.1183/13993003.01932-2021.
    1. Rattanaburi S, et al. Bacterial microbiota in upper respiratory tract of COVID-19 and influenza patients. Exp Biol Med. 2022;247:409–415. doi: 10.1177/15353702211057473.
    1. Zhang H, et al. Metatranscriptomic characterization of coronavirus disease 2019 identified a host transcriptional classifier associated with immune signaling. Clin Infect Dis. 2020. 10.1093/cid/ciaa663.
    1. Whelan FJ, et al. The loss of topography in the microbial communities of the upper respiratory tract in the elderly. Ann Am Thorac Soc. 2014;11:513–521. doi: 10.1513/AnnalsATS.201310-351OC.
    1. Ziegler CGK, et al. SARS-CoV-2 Receptor ACE2 is an interferon-stimulated gene in human airway epithelial cells and is detected in specific cell subsets across tissues. Cell. 2020;181:1016–1035.e19. doi: 10.1016/j.cell.2020.04.035.

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