Cited by 1,619COVID-19 Clinical Research StudiesPneumonia and Respiratory InfectionsRespiratory viral infections research

The DOI matches its Crossref record; 66 of the 72 references it cites were found in a registry or an index; none of the 42 sources its claims cite is checked for support yet.

Co-infections in people with COVID-19: a systematic review and meta-analysis.

Open access

Abstract

Objectives In previous influenza pandemics, bacterial co-infections have been a major cause of mortality. We aimed to evaluate the burden of co-infections in patients with COVID-19. Methods We systematically searched Embase, Medline, Cochrane Library, LILACS and CINAHL for eligible studies published from 1 January 2020 to 17 April 2020. We included patients of all ages, in all settings. The main outcome was the proportion of patients with a bacterial, fungal or viral co-infection. . Results Thirty studies including 3834 patients were included. Overall, 7% of hospitalised COVID-19 patients had a bacterial co-infection (95% CI 3-12%, n=2183, I2=92·2%). A higher proportion of ICU patients had bacterial co-infections than patients in mixed ward/ICU settings (14%, 95% CI 5-26, I2=74·7% versus 4%, 95% CI 1-9, I2= 91·7%). The commonest bacteria were Mycoplasma pneumonia, Pseudomonas aeruginosa and Haemophilus influenzae. The pooled proportion with a viral co-infection was 3% (95% CI 1-6, n=1014, I2=62·3%), with Respiratory Syncytial Virus and influenza A the commonest. Three studies reported fungal co-infections. Conclusions A low proportion of COVID-19 patients have a bacterial co-infection; less than in previous influenza pandemics. These findings do not support the routine use of antibiotics in the management of confirmed COVID-19 infection.

Overview

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Written from the paper’s full text.

TL;DR

This systematic review and meta-analysis found that bacterial co-infections were uncommon in hospitalised COVID-19 patients, with a pooled proportion of 7%, and viral co-infections in 3%. The authors conclude these findings do not support routine empirical antibiotics for confirmed COVID-19.

Key findings

  • Among 30 studies and 3834 patients, the pooled proportion of laboratory-confirmed bacterial co-infection in hospitalised COVID-19 patients was 7% (95% CI 3–12%, n=2183, I²=92.2%).
  • Bacterial co-infections were higher in ICU-only studies than in mixed ward/ICU studies: 14% (95% CI 5–26%, n=204, I²=74.7%) versus 4% (95% CI 1–9%, n=1979, I²=91.7%).
  • The pooled proportion with viral co-infection was 3% (95% CI 1–6%, n=1014, I²=62.3%); RSV and influenza A were the commonest. The commonest bacteria were *Mycoplasma pneumoniae* (42% of 27 confirmed bacterial detections), *Pseudomonas aeruginosa* (12%), and *Haemophilus influenzae* (12%).
  • Co-infected patients were more likely to die than non-co-infected patients (pooled OR 5.82, 95% CI 3.4–9.9, n=733, 4 studies, I²=85.4%).

Methods

  • Systematic review and meta-analysis searching Embase, Medline, Cochrane Library, LILACS, and CINAHL from 1 January 2020 to 17 April 2020, with no language restriction; single case reports and studies with fewer than ten participants were excluded.
  • Included 30 studies (29 observational studies and 1 RCT) with 3834 patients; most data were from adults, with three small paediatric-only studies (n=86), and 23 of 30 studies were from China.
  • Pooled proportions were estimated using a random-effects model (DerSimonian Laird weights) with Freeman-Tukey double arcsine transformation, exact binomial 95% CIs, and heterogeneity assessed by I²; analyses used Stata 16.0.

Limitations

  • Stated: more than three-quarters of included studies were from China early in the pandemic; most were case series with limited co-infection details, few data on timing of co-pathogen detection, and possible under-investigation of secondary infections.
  • Stated: broad-spectrum antibiotic use may have reduced bacterial culture sensitivity and underestimated co-infections; some reported bacteria may have been colonisers rather than causative pathogens; healthcare-system differences may limit global representativeness, and most included patients were hospitalised.
  • Stated: there was significant unexplained heterogeneity, especially for bacterial co-infections; many participants remained hospitalised at censor date, likely underestimating later secondary infections; publication bias was not assessed. Evident from the text: the pooled estimates rely heavily on observational case series with risk-of-bias concerns in selection and outcome ascertainment.

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Integrity signals

Registry

Crossref · 10.1016/j.jinf.2020.05.046

Cites

66 of 66 references verified0 citation errors · 0 not checkable

Statistics

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Claims the paper makes

32 Own result · 28 Not checked yet · 13 Own interpretation · 8 No basis given · 5 Own method

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Show all 48 claims

  • It may state two separate claims as one. 21
  • Probably not a substantial claim. 24
38 of 38
  • The paper relies on this without support.

    This is the first systematic review to evaluate the burden of co-infections in patients with confirmed SARS-CoV-2 infection.

    “To our knowledge, our study is the first systematic review to evaluate the burden of co-infections in patients with confirmed SARS-CoV-2 infection.”
  • The paper relies on this without support.

    The pooled proportion of bacterial co-infection is valid despite significant unexplained heterogeneity.

    “There was significant heterogeneity among studies, particularly in the meta-analyses of bacterial co-infections which was not accounted for by age group or setting.”
  • The paper relies on this without support.

    The previous influenza pandemic co-infection proportions are comparable to COVID-19.

    “we found that the overall proportion of COVID-19 patients who have a bacterial coinfection is lower than in previous influenza pandemics”
3 of 3

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Citations

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Research works printed but not linked: 1

  1. Mo, 2020, Clinical characteristics of refractory COVID-19 pneumonia in Wuhan, China. Clin Infect Dis.

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Metadata

Authors
Lansbury, L., Lim, B., Baskaran, V., & Lim, W. S.
Affiliations
  • University of Nottingham (GB)
  • University of Cambridge (GB)
  • Nottingham University Hospitals NHS Trust (GB)
Corresponding author
  • Lansbury, Louise
  • Lim, Benjamin
  • Baskaran, Vadsala
  • Lim, Wei Shen
Venue
Journal of Infection
Publisher
Elsevier BV
Published
2020-08
Volume
81
Issue
2
Pages
266-275
ISSN
0163-4453 (ISSN-L)
OpenAlex
W3029242200
Cited by
1,619
References
72
Citations by year
2026: 67 · 2025: 88 · 2024: 170 · 2023: 304 · 2022: 393 · 2021: 463 · 2020: 132
FWCI
15.26
Type
journal article
Language
en
Open access
Locations
  • Journal of Infection (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Repository@Nottingham (University of Nottingham) (acceptedVersion, other-oa)
  • Repository@Nottingham (University of Nottingham) (submittedVersion, cc-by-nc-nd)
Funders
National Institute for Health and Care Research
Topics
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
  • Health Sciences › Medicine › Epidemiology › Pneumonia and Respiratory Infections
  • Health Sciences › Medicine › Epidemiology › Respiratory viral infections research
Keywords
COVID-19 pandemic, bacterial co-infection, viral coinfection, fungal co-infection, Mycoplasma pneumoniae pneumonia, Pseudomonas aeruginosa, Haemophilus influenzae, respiratory syncytial virus, influenza A virus, intensive care unit patients, antibiotic use, hospitalized patients
MeSH terms
Betacoronavirus, COVID-19, SARS-CoV-2, Bacterial Infections, Humans, Mycoses, Pneumonia, Viral, Virus Diseases, Coronavirus Infections, Pandemics, Coinfection

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