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Co-Infection and Antimicrobial Stewardship

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This page undergoes regular review and was last comprehensively reviewed on June 21, 2021. Some sections may reflect more recent updates.


Bacterial secondary infections in patients with active COVID-19 do not appear to be common, according to epidemiologic data from multiple countries. However, early in the pandemic, empiric treatment for bacterial and fungal secondary infections in hospitalized COVID-19 patients was common (Vaughn, August 2020Dierenger, 2020). A meta-analysis found that 71.9% of patients hospitalized with COVID-19 before mid-April 2020 received antibiotics, despite the fact that only 6.9% of these admissions were also associated with bacterial infections (Langford, July 2020). 

Regarding respiratory viruses, early in the course of the pandemic several observational cohorts reported widely varying rates, with the highest being 50% (Yue, June 2020; Hashemi, July 2020), but numerous studies examining influenza rates in other countries in the setting of COVID-19 control measures have shown significantly decreased activity (Fong, May 2020; Kuo, August 2020; Soo, August 2020;Olsen, September 2020). Given enhanced infection control measures due to the pandemic, an overall drop in respiratory viruses during the winter of 2020 has been noted in the literature (Britton, September 2020Yeoh, June 2021Nolen, June 2021). 

In terms of fungal infections, relatively high rates (over a quarter) of coinfection with Aspergillus have been reported in a few observational cohorts and case series of patients with COVID-19 requiring mechanical ventilation, but this has not been consistently reported across studies; currently, the true incidence of COVID-19 associated pulmonary aspergillosis is not known and studies are ongoing (Bartoletti, July 2020). A rise in coinfections with mucormycosis has been reported in India (Hoenigl, June 2021). 

Antimicrobial stewardship programs have been shown to optimize antimicrobial use, improve patient outcomes and reduce harms from excess use, such as antimicrobial resistance (CDC, April 2015). Although antimicrobial stewardship programs have not traditionally been involved in pandemic response efforts, many aspects of the management of the COVID-19 pandemic in the United States, particularly in hospitals, may be augmented by traditional stewardship expertise. Examples include utilizing preexisting ASP communication infrastructure to disseminate COVID-19 related guidelines to frontline providers, assessing compliance with guidelines, incorporating experimental treatments into existing pre-authorization paradigms and ensuring appropriate use of therapies. ASPs have also harnessed existing skillsets of stewardship pharmacists and physicians to attain and allocate experimental agents (e.g., remdesivir and convalescent plasma) through available pathways, such as compassionate use or expanded access from pharmaceutical companies, emergency use authorization from the federal government or through patient enrollment in randomized clinical trials (Stevens, March 2020). 

However, due to diversion of stewardship efforts to pandemic responsibilities and away from core activities, inpatient antibiotic use may have proceeded unchecked for several months, potentially contributing to harms such as antimicrobial resistance (Nori, September 2020). The long-term impact of antibiotic overuse during COVID-19 remains to be seen (Stevens, March 2020). 

Healthcare-associated infections also have been affected by the pandemic due to a number of factors, including adherence to infection prevention measures, PPE availability, burnout, workforce challenges and competing priorities. In the United States, central-line associated bloodstream infections had been on the decline for years but significantly rose in 2020, according to CDC data (Patel, March 2021). 

Here we review select key literature evaluating the incidence of bacterial and fungal coinfections as well as antimicrobial use in patients with COVID-19, focusing on the largest studies and those with the highest level of evidence and most generalizable results.  


Key Literature

In summary: Current data indicate that bacterial coinfections with SARS-CoV-2 infection are relatively infrequent (likely occurring in <10% of hospitalized COVID-19 patients). The literature does not support routine use of empiric antibiotics in the management of confirmed COVID-19 infection. Objective findings that increase the concern for bacterial superinfection include rise in leukocyte counts, lobar consolidation or evidence of necrotizing infection on chest imaging and recrudescence of fever after initial defervescence. Fungal superinfection (with Aspergillus) is also a concern, but the true incidence has not been defined; risk factors for fungal superinfection include steroid use, invasive catheters and prolonged mechanical ventilation. Antimicrobial stewardship programs can help optimize antimicrobial use during the pandemic. Continued investigation into optimal antimicrobial stewardship program interventions to limit antibiotic overuse during the COVID-19 pandemic is warranted. 

Antibiotic prescribing in patients with COVID-19: rapid review and meta-analysis (Langford, January 2021). 

Overall, in this literature review of 154 studies, three-quarters of patients with COVID-19 received antibiotics, with prescribing rates significantly higher than the estimated prevalence of bacterial co-infection. Inappropriate antibiotic use is high in patients with COVID-19 and antimicrobial stewardship interventions are recommended. 

Study population: 

  • 154 publications conducted between December 8, 2019 and May 21, 2020 of patients with COVID-19 who were prescribed an antibiotic during the course of their illness. 
    • Publications were sourced from MEDLINE, COVID Epub and EMBASE. 
  • Inclusion criteria were:  
    • Humans with laboratory-confirmed SARS-CoV-2 infection across all health care settings (i.e. hospital, community, long-term care) and age groups (pediatric and adult patients) 
    • Randomized controlled trials;  
    • Cohort studies;  
    • Case series with >10 patients;  
    • Experimental or observational design that evaluated antibiotic prescribing.  
  • Study designs were primarily retrospective in nature (n=135), followed by prospective cohort (n=11), randomized controlled (n=6) and mixed prospective and retrospective design (n=1).  
  • Most studies took place in China (n=115 studies; 21,852 patients), followed by the United States (n=12 studies, 2,302 patients); Italy (n=11 studies, 3,785 patients); and South Korea (n=4 studies, 5,321 patients). 
  • The median patient age was 53 years (IQR 44 to 61, range 3-72).  
  • The majority of studies evaluated exclusively adults (n=91) whereas a smaller number of studies (n=10) included only children.  
  • Commonly reported comorbidities included diabetes (median 12%, IQR 8-21%); cardiovascular disease (median 12%, IQR 6-18%); COPD (median 4%, IQR 2-7%); and malignancy (median 3%, IQR 1-6%). A history of smoking was reported in a median of 10% of patients (IQR 6-19%). 
  • Most studies evaluated hospitalized patients (n=133 studies, 30,212 patients) including a mix of both general ward and critically ill patients.  
  • The median proportion of patients requiring mechanical ventilation support was 16% (IQR 5-27%), based on 114 studies that reported this variable. 

Primary endpoint: 

  • To determine the prevalence of antibiotic use and identify the predictors of antibiotic use in patients with COVID-19. 

Key findings: 

  • Out of a total of 35,263 patients, 30,623 were assessed for antibiotic prescribing, of whom 19,102 (62.4%) received at least one antibiotic agent.  
  • The prevalence of antibiotic prescribing was 74.6% (95% CI 68.3-80.0%), with significant heterogeneity (I2=99%). 
  • Of all included studies, 28 (18.2%) provided data on antibiotic classes prescribed. 
    • In these studies, 4,721 patients were evaluated and 2,482 patients received 3,058 antibiotic agents.  
    • Of 10 classes of antibiotics studied, the most common antibiotic classes prescribed were fluoroquinolones (n=612, 20.0%), macrolides (n=579, 18.9%), beta-lactam/beta-lactamase inhibitors (n=459, 15.0%) and cephalosporins (n=459, 15.0%). 
  • The prevalence of antibiotic use across regions had high heterogeneity with I2= 99%.  
    • Antibiotic prescribing in Europe was 63.1% (95% CI 41.7 to 80.4%); in North America (USA) was 64.8% (95%CI 54.0 to 74.2%); in China was 76.2% (66.8 to 82.3%); in the Middle East was 86.0% (95%CI 77.4 to 91.7%); and in East/Southeast Asia (excluding China) was 87.5% (47.8 to 98.2%). 
  • There was a trend towards reduced antibiotic prescribing as the pandemic continued. Studies ending enrollment and/or follow up in January 2020 showed the highest prescribing prevalence (85.8%, 95% CI 67.9-94.6%) and studies ending in April 2020 showed the lowest (62.6%, 95% CI: 50.7-73.1%). 
  • On univariable meta-regression, antibiotic prescribing was lower in children (prescribing prevalence odds ratio (OR) 0.10, 95% CI 0.03-0.33) compared to adults.  
  • Antibiotic prescribing was higher with increasing patient age (OR 1.45/ 10-year increase, 95% CI 1.18-1.77) and higher with increasing proportion of patients requiring mechanical ventilation (OR 1.33/10% increase, 95% CI 1.15-1.54).  
  • Estimated bacterial co-infection was 8.6% (95% CI 4.7-15.2%) from 31 studies, heterogeneity between studies I2=96%. 


  • Disproportionate representation from Asia potentially limits the generalizability of the results to other areas affected by COVID-19. 
  • Antibiotic prescribing data are of uncertain quality and there was limited data on antibiotic prescribing details including indication, selection of antibiotic, timing and duration of therapy. 
  • There was high heterogeneity between studies. 

Antibiotic Consumption and Stewardship at a Hospital Outside of an Early Coronavirus Disease 2019 Epicenter (Buehrle, November 2020).

Overall, in this single-center study assessing antibiotic consumption and antimicrobial stewardship practices in a hospital with a small number of COVID-19 patients, there was an association of significant reductions in monthly antibiotic days of therapy and bed days of care compared to prior years; however, overall antibiotic days of therapy per 1,000 bed days of care, primarily non-antipseudomonal penicillin and macrolide (i.e., azithromycin), significantly increased. 

Patient population:

  • Patients admitted to the Pittsburgh VA health system from November 2017 through June 2020 (monthly data) and 16, 2020 through July 4, 2020 (weekly data).

Primary endpoint:

  • Antibiotic utilization and patient bed days of care for November 2017 through June 2020 (monthly data) and 16, 2020 through July 4, 2020 (weekly data).

Key findings:

  • During March to June 2020, there was a monthly adjusted average decrease of 151.5 antibiotic days of therapy per month compared with January 2018 through February 2020 (6.5% monthly reduction; p<0.001).
  • There was an adjusted average decrease of 285 BDOC per month for March to June 2020 (7.8% monthly reduction; p< 0.001).
  • Antibiotic DOT per 1,000 BDOC increased by an adjusted average of 8.1 per month for March to June 2020 (1.3% monthly increase; p<0.001).
  • Significant increases were observed in monthly DOT per 1,000 BDOC of non-antipseudomonal penicillins (monthly increase, 7.0 DOT/1,000 BDOC; p<0.001) and macrolides (monthly increase, 3.6 DOT/1,000 BDOC; p<0.001).
  • During March to June 2020, antibiotic DOT and BDOC decreased by weekly averages of 25.6 (5.1% weekly reduction; p<0.001) and 49.5 (5.8%; p<0.001), respectively, before rebounding thereafter.
  • Bacterial infections were diagnosed in 31% (5/16) of patients with COVID-19; antibiotics were administered to 56% (9/16) patients.
    • Antibiotics were prescribed against infections present upon admission or acquired in-hospital (19% each [3/16]), or as short-term (<=4-days) empirical therapy (31% [5/16]).


  • Retrospective observational study; bias is possible.
  • The changes seen in BDOC and antibiotic prescribing practices may not have been related to COVID-19.
  • Single-center study, which may limit generalizability to other centers.


Changes in Antimicrobial Utilization During the COVID-19 Pandemic After Implementation of a Multispecialty Clinical Guidance Team (Staub, October 2020).

Overall, in this retrospective study conducted evaluating antimicrobial usage pre- and post-pandemic, antibiotic use in patients hospitalized with COVID-19 was common. The implementation of a daily COVID-19 huddle with evidence-based facility guidelines resulted in a decrease in antibiotic use.

Patient population:

  • Hospitalized COVID-19 patients on internal medicine and medical intensive care unit provider teams at Vanderbilt University Medical Center.

Primary endpoint:

  • The difference in change in weekly antimicrobial use for COVID teams and change in weekly antibiotic use for non-COVID teams, calculated by comparing teams to their own performance, separately for IM and MICU teams, during three time periods: pre-COVID-19; during COVID-19 but before implementation of a COVID-19 huddle; and during COVID-19 after implementation of a COVID-19 huddle.
  • The study period was separated into pre- (Dec. 1-Feb. 29) and 2 post-COVID-19 (March 1- March 21 and March 22-May 15) periods.

Key findings:

  • In the initial COVID-19 period, compared to the pre-COVID-19 period, IM and MICU teams increased weekly antibiotic use by 145.3 (95% CI: 35.1 to 255.5) and 204.0 (95% CI: -16.9 to 424.8) days of therapy, respectively, compared to non-COVID-19 teams.
  • In the intervention period, IM and MICU COVID-19 teams both had significant weekly decreases of 362.3 (95% CI: -443.3 to -281.2])and 226.3 (95% CI -381.2 to –71.3) days of therapy.
  • Of 131 patients hospitalized with COVID-19, 86 (65.6%) received antibiotics; no specific patient factors were significantly associated with expected antibiotic days of therapy.
  • After implementation of the COVID-19 huddle that universally discouraged azithromycin use for COVID-19 treatment alone and encouraged antibiotic cessation in patients whose symptoms could be attributed to COVID-19, there was a significant decrease in azithromycin use for COVID-19 teams versus non-COVID-19 teams compared to pre-COVID-19 use.


  • Retrospective observational study; bias is possible.
  • Antibiotic use was evaluated only in hospitalized patients cared for by IM and MICU teams to reduce confounding from unmeasured differences in team structures and specialty-specific clinical approaches.
  • The relatively small COVID-19 patient population may have reduced power to detect significant associations between antibiotic use and patient characteristics.  


Empiric Antibacterial Therapy and Community-onset Bacterial Coinfection in Patients Hospitalized with COVID-19: A Multi-Hospital Cohort Study (Vaughn, August 2020).

Overall, in this large retrospective cohort study in 38 hospitals, there was a high use of early empiric antibacterial therapy in patients hospitalized with COVID-19, despite low prevalence of confirmed community-onset bacterial coinfections.

Patient population:

  • Randomly sampled cohort of 1,705 patients hospitalized with COVID-19 in 38 hospitals in Michigan.

Primary endpoint:

  • The percentage of patients prescribed early empiric antibacterial therapy (any intravenous or oral antibacterial on day 1 or 2 of hospitalization).

Key findings:

  • Of 1,705 patients with COVID-19, 56.6% were prescribed early empiric antibacterial therapy.
  • 3.5% of the cohort (59/1,705) had a confirmed community-onset bacterial infection, including 1.8% (31/1,705) who had a positive blood culture and 1.7% (29/1,705) who had a bacterial respiratory pathogen identified.
  • In those who received empiric antibacterial therapy, the median inpatient duration was 3 days (IQR 2-6).
  • The most commonly prescribed empiric antibacterials were ceftriaxone (38.9% [663/1,705]), vancomycin (13.8% [235/1,705]), doxycycline (10.9% [185/1,705]) and cefepime (10.4% [177/1,705]).
  • Total days of inpatient, post-discharge, and total antibacterial therapy were 4,158 days/1,000 patients, 484 days/1,000 patients and 4,628 days/1,000 patients, respectively.
  • Patients were more likely to receive early empiric antibacterial therapy if they were older, had a lower body mass index, had more severe disease (e.g., respiratory support, severe sepsis), had a lobar infiltrate or were admitted to a for-profit hospital; patients admitted at a later date in the surge were less likely to receive empiric antibacterials.


  • Retrospective observational study; bias is possible.
  • There was incomplete data on secondary bacterial infections, which may develop later during hospitalization. It is likely that, for some patients, bacterial coinfections develop later in hospitalization.
  • Azithromycin as an antibacterial was excluded as they were unable to distinguish between azithromycin use as an antibacterial vs. targeted therapy for COVID-19; thus, there may be an underestimate of the true prevalence of antibacterial overuse.

Epidemiology of invasive pulmonary aspergillosis among COVID-19 intubated patients: a prospective study (Bartoletti, July 2020).

Overall, in this prospective cohort study of patients with COVID-19 admitted to ICUs in Bologna, Italy, during the height of their initial surge, nearly 30% of patients met criteria for probable or proven CAPA. Whether these results are generalizable is unclear.

Patient population:

  • 108 adult patients admitted with critical COVID-19 and requiring mechanical ventilation.

Primary endpoint:

  • The incidence of COVID-19 associated invasive pulmonary aspergillosis in the cohort.
    • To meet criteria for CAPA, patients had to be admitted to the ICU with pulmonary infiltrates (entry criterion) and have at least 1 of the following: serum galactomannan index more than 0.5, BAL galactomannan index more than 1.0, positive Aspergillus BAL culture or cavitating infiltrate (not attributed to another cause) in the area of the pulmonary infiltrate.

Key findings:

  • Every patient in the cohort underwent a full evaluation for CAPA, including bronchoscopy.
  • Probable CAPA was diagnosed in 30 (27.7%) patients after a median of 4 (2–8) days from intensive care unit admission.
  • Patients with CAPA (44% vs. 19%, p=0.002) had a significantly higher 30-day mortality rate compared with patients not fulfilling criteria for aspergillosis.
  • The association between CAPA (OR, 3.53; p=0.014) with 30-day mortality from ICU admission was confirmed, even after adjustment for confounders with a logistic regression model.


  • Retrospective observational study; bias is possible.
  • Single-city study in Italy, which at the time had one of the highest COVID-19 incidence and mortality rates in the world; the patients admitted to the ICUs in this setting (and during this time) may have been more ill than those admitted in other parts of the world, and results may not be generalizable.
  • Every patient in the cohort underwent an evaluation for CAPA regardless of symptoms or clinical presentation; it is possible some of the patients found to have probably CAPA would not have had clinically significant disease. In addition, culture and PCR positivity was only found in 63% and 67% of the cases of presumed CAPA, respectively.


Incidence of coinfections and superinfections in hospitalized patients with COVID-19: a retrospective cohort study (Garcia-Vidal, July 2020).

Overall, in this retrospective study conducted in Barcelona, coinfections with COVID-19 were uncommon, and few patients developed superinfections during hospitalization. Patients who did develop superinfections had a longer hospital length of stay and higher mortality rate. 

Patient population:

  • 989 consecutive hospitalized patients with COVID-19 who were either discharged or died in Barcelona from Feb. 28-April 22, 2020.

Primary endpoint:

  • The incidence of coinfections and superinfections in the cohort.
  • If diagnosis of coinfection/superinfection was at the time of or within the first 24 hours of COVID-19 hospital admission, these infections were defined as community-acquired coinfections.
  • If diagnosis occurred >=48 hours after admission for COVID-19, these infections were defined as hospital-acquired superinfections.

Key findings:

  • Of 989 patients, 72 (7.2%) had 88 microbiologically confirmed coinfections/secondary infections: 74 were bacterial, 7 fungal and 7 viral.
    • The 74 bacterial infections were diagnosed in 61 of 88 patients.
    • The most common bacteria isolated were Streptococcus pneumoniae, with 12 cases; aureus, 12; Pseudomonas aeruginosa, 10; Escherichia coli, 7; and Klebsiella pneumoniae, 6.
  • Community-acquired coinfection at COVID-19 diagnosis was uncommon (3.1%, 31/989) and mainly caused by pneumoniae and S. aureus.
  • A total of 51 hospital-acquired bacterial superinfections, mostly caused by aeruginosa and E. coli, were diagnosed in 43 patients (4.7%), with a mean (SD) time from hospital admission to superinfection diagnosis of 10.6 (6.6) days.
  • Overall mortality was 9.8% (97/989), with hospital-acquired superinfection rates associated with longer hospital stays, more ICU admissions and higher mortality rates.


  • Retrospective observational study; bias is possible.
  • Retrospective study conducted in a single country, limiting generalizability to other countries.
  • No systematic testing for coinfections was performed, and it is possible that either some attending physicians did not order microbiologic tests for their patients or some patients may have had coinfections or superinfections that were not documented by the microbiologic tests performed.
  • As this study included a cohort of patients currently discharged or dead, some patients with severe COVID-19 infection that required ICU admission, mechanical ventilation and prolonged length of hospital stay remained hospitalized. Therefore, superinfection rates may have been higher than reported. 

Coinfections in people with COVID-19: a systematic review and meta-analysis (Lansbury, May 2020).

Overall, in the systematic review and meta-analysis of 30 studies evaluating the burden of coinfections in patients with COVID-19, the overall proportion of COVID-19 patients who had a bacterial coinfection was low (7%).

Patient population:

  • 30 studies published Jan. 1, 2020-April 17, 2020 including 3,834 hospitalized patients with COVID-19.
  • 29 observational studies and 1 randomized controlled trial were included.
  • 23 (77%) of the included studies were from China, 3 from the U.S. (10%), 2 from Spain (6.7%) and 1 each (3.3%) from Thailand and Singapore.
  • Most data were for adults (range of median ages 42-63 years), with only 3 small studies reporting data exclusively from children (n=86).

Primary endpoint:

  • The proportion of patients with a bacterial, fungal or viral coinfection.

Key findings:

  • Antibiotic use was reported in 17 studies, with >90% of patients receiving empiric antibiotics in 10 studies.
  • 7% of hospitalized COVID-19 patients had a bacterial coinfection (95% CI: 3-12%, n=2,183, I2=92.2%).
  • A higher proportion of ICU patients had bacterial coinfections than patients in mixed ward/ICU settings (14%, 95% CI: 5-26, I2=74.7% versus 4%, 95% CI: 1-9, I2= 91.7%).
  • Specific coinfecting pathogens were identified in 17 studies.
    • The most frequently detected bacterial pathogen was Mycoplasma pneumoniae (42%), followed by Pseudomonas aeruginosa (12%) and Haemophilus influenzae (12%).
  • COVID-19 patients with a coinfection were more likely to die than patients who did not have a coinfection (pooled OR 5.82, 95% CI: 3.4–9.9, n=733, 4 studies, I2=85.4%).
  • 38% of observational studies had an element of selection bias, as the patients they reported may not have been truly representative of patients with COVID-19.
  • 72% of the studies were at some risk of bias, which was generally attributable to incomplete follow-up of patients, with most studies reporting that many patients were still hospitalized at the censor date.


  • There was significant heterogeneity among studies, particularly in the meta-analyses of bacterial coinfections, which was not accounted for by age group or setting.
  • A number of included patients remained hospitalized at the censor date of most studies; underestimation of secondary bacterial infections developing later in the course of the disease is likely.
  • There was no assessment of publication bias.

Bacterial and Fungal Coinfection in Individuals with Coronavirus: A Rapid Review to Support COVID-19 Antimicrobial Prescribing (Rawson, May 2020).

Overall, in this literature review of 18 studies, there was a low rate (8%) of bacterial coinfections in patients with COVID-19; however, use of broad-spectrum antibiotics was high (72%).

Patient population:

  • 18 studies including 7,136 hospitalized patients with other coronaviruses, SARS, MERS or SARS-CoV-2.

Primary endpoint:

  • The incidence of bacterial/fungal coinfections.

Key findings:

  • 9 of 18 (50%) studies reported on COVID-19, 5 of 18 (28%) reported on SARS-1, 3 of 18 (17%) other coronaviruses and 1 of 18 (6%) reported on MERS.
  • Of the COVID-19 studies, 7 of 9 (78%) reports were from China, with 2 of 9 (22%) from the United States.
  • Studies reporting on COVID-19 reported 62 of 806 (8%) cases of bacterial/fungal coinfection.
  • Secondary analysis demonstrated wide use of broad-spectrum antibiotics, 1,450/2,010 (72%), despite low evidence for bacterial coinfection.


  • No antimicrobial stewardship interventions were described in reviewed studies.
  • This study included coronavirus infections predominantly from Asia, which may limit the generalizability of the findings.
  • Many studies failed to differentiate the health care setting and stage of COVID-19 infection where coinfection was identified.
  • Studies presented in this article were not graded for quality and potential bias, making it difficult to weigh any recommendations based on current evidence.

Additional Literature

Inpatient antibiotic utilization in the Veterans’ Health Administration during the coronavirus disease 2019 (COVID-19) pandemic Dieringer, Oct 2020). This retrospective cohort study compared antibiotic prescribing practices across the Veterans’ Health Administration between 2015-2019 with prescribing practices from the start of the COVID-19 pandemic to August 2020. From 2015 to 2019, antibiotic use between January and May decreased from 638 to 602 days of therapy per 1,000 days present, while the corresponding months in 2020 saw antibiotic utilization rise to 628 days of therapy per 1,000 days present.

Few bacterial coinfections but frequent empiric antibiotic use in the early phase of hospitalized patients with COVID-19: results from a multicenter retrospective cohort study in The Netherlands (Karami, October 2020). In this retrospective study in 925 Dutch patients hospitalized with COVID-19, 12 (1.2%) had a documented bacterial coinfection (75.0% pneumonia) within the first week. On presentation 556 patients received antibiotics for a median duration of 2 days (60.1%; range 33.3-73.4%; IQR 1-4). Mean adherence to the local guideline on empiric antibiotic therapy on day 1 was on average 60.3% (range 45.3%-74.7%).


Bacterial pneumonia coinfection and antimicrobial therapy duration in SARS-CoV-2 (COVID-19) infection (Townsend, September 2020). This retrospective study assessed antibiotic prescription, choice, duration, microbiological samples and culture positivity rate in 117 SARS-CoV-2 positive patients. Of those, 84 patients were treated for presumed lower respiratory tract infection (72%, 84/117), while 11 were treated for an alternative source of bacterial coinfection (9%, 11/117). The lower respiratory tract infection bacterial coinfection rate was 6% (7/117). C-reactive protein level, oxygen requirement and positive cultures were associated with prolonged duration of therapy.

Antibiotic use in patients with COVID-19: A “snapshot” Infectious Diseases International Research Initiative (ID-IRI) survey (Beovic, August 2020). In an international web-based survey to investigate the pattern of antibiotic use as reported by physicians involved in treatment of COVID-19, 166 participants completed the survey from 23 countries and 82 different hospitals. Clinical presentation was noted as the most important reason for the start of antibiotics (mean score = 4.07 and SD = 1.095 on grading scale from 1 to 5). For patients in the general ward, combination of β-lactams and macrolides or fluoroquinolones was reported by 52.4% (n=87). In patients in the ICU, piperacillin/tazobactam was the most commonly prescribed antibiotic. The mean reported duration of antibiotic treatment was 7.12 (SD = 2.44) days.


Bacteremia and Blood Culture Utilization During COVID-19 Surge in New York City (Sepulveda, July 2020). In this retrospective cohort analysis of 88,201 blood cultures from 28,011 patients at a multicenter network of hospitals within New York City, ordering volume of blood cultures increased by 34.8% in the second half of March 2020 compared to the level in the first half of the month. The rate of bacteremia was significantly lower among COVID-19 patients (3.8%) than among COVID-19-negative patients (8.0%) and those not tested (7.1%) (p<0.001). COVID-19 patients had a high proportion of organisms reflective of commensal skin microbiota, which, when excluded, reduced the bacteremia rate to 1.6%.

Bacterial and fungal coinfections in COVID-19 patients hospitalized during the New York City pandemic surge (Nori, June 2020). In this retrospective study of 5,853 COVID-19 patients admitted to Montefiore Medical Center from March 1-May 31, 2020, 4,130 (71%) received at least one antibiotic dose. Less than 5% of these patients had a bacterial or fungal coinfection. An increased number of carbapenem-resistant Enterobacteriaceae isolates were identified compared with the same time frame in 2019.


COVID-19 associated pulmonary aspergillosis (Koehler, April 2020). In this retrospective chart review of all patients with COVID‐19 associated acute respiratory distress syndrome admitted to a university hospital in Germany, COVID‐19 associated invasive pulmonary aspergillosis was found in five of 19 consecutive critically ill patients with moderate to severe acute respiratory distress syndrome.

COVID-19–associated Pulmonary Aspergillosis (Van Arkel, June 2020). In this observational cohort study of 135 adult patients hospitalized with COVID-19 in the Netherlands, 31 (23%) required mechanical ventilation. Eleven ICU patients with COVID-19 developed a secondary infection, of whom six (19.4%) were presumed to have invasive pulmonary aspergillosis. However, of these 6 patients, only 3 had a positive BAL ; 5 were culture positive for Aspergillus fumigatus.



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