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Evidence about public-health measures

 

We continue to add evidence syntheses to this webpage as we harvest and process weekly updates from ‘high-yield, high quality’ sources of evidence syntheses and as we add new sources. More details are available about the context for the inventory, our approach to developing and maintain it, and tips for using it. Similar webpages are available for evidence about the clinical management of COVID-19 and related conditions, health-system arrangements, and economic and social responses.

Broad and specific decisions Criteria for 'best evidence synthesis' Details to support relevance assessment Additional decision-relevant details Citation
Date of last search Quality (AMSTAR) rating Evidence profile (e.g., GRADE) available              Key findings
Living evidence synthesis Type of synthesis              Type of question
Infection prevention                
  Personal protection                
    Washing hands 2020-04-17
4/9 No  Hand hygiene combined with the use of masks in community settings appears to be more protective against coranaviruses and other infectious respiratory viruses than either approach in isolation No  Rapid review  Benefits and harms  MacIntyre CR & Chughtai AA. A rapid systematic review of the efficacy of face masks and respirators against coronaviruses and other respiratory transmissible viruses for the community, healthcare workers and sick patients. Int J Nurs Stud. 2020;108:103629. 
      2020-04-25
8/11  No  Studies from the pre COVID-19 era show that proper hand-hygiene methods combined with the use of face masks may reduce the rate of influenza-like-illnesses in community settings No  Full review  Benefit and harms  Aggarwal N, Dwarakanathan V, Gautam N, Ray A. Facemasks for prevention of viral respiratory infections in community settings: A systematic review and meta-analysis. Indian J Public Health. 2020;64(Supplement):S192-S200. 
 
    Wearing masks* 2020-05-03 11/11 Yes  Large reductions in risk of  viral infections may be possible with the use of masks, with N95 or similar respirators more likely to lead to greater reductions compared to disposable surgical masks or other reusable masks
Yes (row content last updated on 2021-01-18) Full review Benefits and harms  Chu DK, Akl EA, Duda S, et al. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis [published online ahead of print, 2020 Jun 1]. Lancet. 2020;S0140-6736(20)31142-9. doi:10.1016/S0140-6736(20)31142-9
      2020-10-02
7/10 No  Whereas no research was found on the effectiveness of wearing masks in community settings for COVID-19, studies on SARS and influenza showed that the evidence for wearing masks is stronger in healthcare settings compared to community settings Yes (row content last updated on 2021-01-18) Rapid review  Benefits and harms  Chou R, Dana T, Jungbauer R, Weeks C, McDonagh MS. Masks for prevention of COVID-19 in community and healthcare settings: A living rapid review. Annals of internal medicine. 2020;M20-3213. 
      Not specified
5/11  Yes  Cloth face masks and facial coverings worn by the general public appear to be an effective approach for source protection (i.e., reducing virus transmission by the wearer) while also protecting the wearer No  Rapid review  Benefits and harms  The British Academy. Face masks and coverings for the general public: Behavioural knowledge, effectiveness of cloth coverings and public messaging. Oxford, UK: The British Academy. 2020;  
      2020-05-18
7/11  No  Randomized and non-randomized studies from the pre-COVID-19 era show insufficient reporting of data on serious harms of face masks, with discomfort and irritation the only reported downsides  No  Full review  Benefits and harms  Bakhit M, Krzyzaniak N, Scott, A, Clark J, Glasziou P, Del Mar C. Downsides of Face Masks and Possible Mitigation Strategies: A Systematic Review and Meta-Analysis. MedRxiv 2020. 
    Wearing personal protective equipment 2020-05-03  11/11  Yes Low certainty evidence suggests N95 respirators and eye protection can lead to a reduction in viral infections Yes (row content last updated on 2021-01-18) Full review Benefits and harms Chu DK, Akl EA, Duda S, et al. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis [published online ahead of print, 2020 Jun 1]. Lancet. 2020;S0140-6736(20)31142-9. doi:10.1016/S0140-6736(20)31142-9
    2020-12-02 6/10 No PPE use by healthcare workers (masks, gloves, gowns and eye protection) has been found to be one of the strongest factors associated with reduced risk of coronavirus infection, with the most consistent associations observed for masks Yes (row content last updated on 2021-01-18) Full review Benefits and harms  Chou R, Dana T, Buckley D, Selph S, Fu R, Totten A. Epidemiology of and Risk Factors for Coronavirus Infection in Health Care Workers. Ann Intern Med 2020; M20-1632
    2020-04-01 9/11 No Evidence from existing trials has not found a statistically significant difference in reductions of influenza-like-illness or influenza cases when mask wearing is compared compared to no masks among healthcare workers
No Full review Benefits and harms Jefferson T, Jones M, Al Ansari L, Bawazeer G, Beller E, Clark J, et al. Physical Interventions to Interrupt or Reduce the Spread of Respiratory Viruses. Part I - Face Masks, Eye Protection and Person Distancing: Systematic Review and Meta-Analysis. MedRxiv 2020.
      2020-04-08
8/10  No The safety of different decontamination methods for reusing surgical masks in clinical settings is uncertain
Yes (row content last updated on 2021-01-18) Full review Benefits and harms Zorko DJ, Gertsman S, O'Hearn K, et al. DECONTAMINATION INTERVENTIONS FOR THE REUSE OF SURGICAL MASK PERSONAL PROTECTIVE EQUIPMENT: A SYSTEMATIC REVIEW [published online ahead of print, 2020 Jul 9]. J Hosp Infect. 2020;S0195-6701(20)30337-6. doi:10.1016/j.jhin.2020.07.007 
      2020-05-18
7/11 No Adherence to wearing masks was found to be significantly higher for surgical/medical masks, compared to N95/P2 respirators No  Full review  Benefits and harms  Bakhit M, Krzyzaniak N, Scott, A, Clark J, Glasziou P, Del Mar C. Downsides of Face Masks and Possible Mitigation Strategies: A Systematic Review and Meta-Analysis. MedRxiv 2020. 
      2020-06-01
7/10  Yes  The effectiveness of using powered air-purifying respirators by healthcare workers to prevent risk of infection is uncertain, but they probably improve comfort compared to other respirators   No  Full review  Benefits and harms  Licina A, Silvers A, Stuart RL. Use of powered air-purifying respirator (PAPR) by healthcare workers for preventing highly infectious viral diseases-A systematic review of evidence. Systematic reviews. 2020;9:173.
      2020-03-20
9/10  Yes  The differences between different types of PPE (e.g., attire, gloves, gowns, types of respirators), and levels of protection for preventing exposure to contaminated fluids among healthcare workers is uncertain  Yes (row content last updated on 2021-01-18) Full review  Benefits and harms  Verbeek J, Rajamaki B, Ijaz S, et al. Personal Protective Equipment for Preventing Highly Infectious Diseases due to Exposure to Contaminated Body Fluids in Healthcare Staff. Cochrane Database Syst Rev 2020;4(4):CD011621. 
      2020-03-20
9/10  Yes  The effectiveness of most PPE modifications for preventing exposure to contaminated body fluids in health care workers is uncertain, although easy to doff gowns, and gown-glove improvements may be better than standard gowns and gloves  Yes (row content last updated on 2021-01-18) Full review  Benefits and harms  Verbeek J, Rajamaki B, Ijaz S, et al. Personal Protective Equipment for Preventing Highly Infectious Diseases due to Exposure to Contaminated Body Fluids in Healthcare Staff. Cochrane Database Syst Rev 2020;4(4):CD011621. 
      N/A (Protocol)
n/a  No  [Protocol - no results yet available] A systematic review analysing the effects of sterilization techniques of N95 respirators is currently being conducted  Yes (row content last updated on 2020-12-07) Protocol  Benefits and harms  Rajaee A, Eshkevari PS, Lenhardt R,Stuart A, Ziegler C. Will Decontamination of N95 Filtering Facepiece Respirators Result in Compromised Performance? A Living Systematic Review. PROSPERO 2020; CRD42020179695. 
      2020-04-23
6/9  No  Limited evidence suggests that there is a low probability of viral carriage on the surgical masks of healthcare workers treating patients with clinical respiratory illnesses, and no studies about the relationship between carriage and clinical outcomes were identified  No  Full review  Other  Jones P, Roberts S, Hotu C, Kamona S. What proportion of healthcare worker masks carry virus? A systematic review [published online ahead of print, 2020 Jun 24]. Emerg Med Australas. 2020;10.1111/1742-6723.13581. doi:10.1111/1742-6723.13581 
      Not specified
4/9  No  Limited evidence was found on the effectiveness of 3D printing of N95 respirators  No  Rapid review  Other  Ontario Health Quality. 3D Printing of N95 Respirators and Face Shields: Supplemental Information. Toronto: 2020. 
      2020-06-02
7/10  No  N95 respirators might reduce the risk of infection compared to surgical masks in healthcare settings but the applicablity of this to the current COVID-19 pandemic is uncertain [Review of studies conducted during COVID-19 and SARS outbreaks] Yes (row content last updated on 2021-01-18) Rapid review  Benefits and harms  Chou R, Dana T, Jungbauer R, Weeks C, McDonagh MS. Masks for prevention of COVID-19 in community and healthcare settings: A living rapid review. Annals of internal medicine. 2020;M20-3213. 
      2020-05-25
4/9  No  The evidence on extending the use or reuse of PPE is mainly focused on masks, suggesting that extended use of a respirator (N95 or equivalent) is safer than intermittent reuse  Yes (row content last updated on 2021-01-18) Rapid review  Other  COVID-19 Critical Intelligence Unit. Extended use or reuse of personal protective equipment. St Leonards, NSW: Agency for Clinical Innovation; 2020. 
    Disinfecting surfaces and facilities Not specified
5/11  No  Different coronaviruses persist on surfaces for several (up to nine) days [Review of studies conducted during the pre-COVID-19 era] No  Full review  Other  Fiorillo L, Cervino G, Matarese M, D'Amico C, Surace G, Valeria P, et al. COVID-19 surface persistence: A recent data summary and its importance for medical and dental settings. International Journal of Environmental Research and Public Health. 2020;17(9):3132. 
      2020-04-24
5/9  No  Temperature and humidity appear to have an important effect on how long SARS-CoV-2 can live on surfaces (from a few hours up to 28 days), and alcohol-based hand rub formulations recommended by WHO are an efficient disinfectatnt agent for surfaces [Review of studies of unknown quality] No  Full review  Other  Noorimotlagh Z, Mirzaee SA, Jaafarzadeh N, Maleki M, Kalvandi G, Karami C. A systematic review of emerging human coronavirus (SARS-CoV-2) outbreak: Focus on disinfection methods, environmental survival, and control and prevention strategies. Environmental Science and Pollution Research. 2020. 
    Physical distancing 2020-05-03 11/11 Yes Physical distancing of more than one metre probably results in a large reduction in risk of viral infections
Yes (row content last updated on 2021-01-18) Full review Benefits and harms Chu DK, Akl EA, Duda S, et al. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis [published online ahead of print, 2020 Jun 1]. Lancet. 2020;S0140-6736(20)31142-9. doi:10.1016/S0140-6736(20)31142-9
      2021-01-21
8/9  No  Synthesis pending
Yes (row content last updated on 2021-01-18) Full review  Benefits and harms  COVID NMA. Social Distancing at Sports Training vs No Access to Sports Training Facilities. 2020. 
      2020-07-29
8/11  No  Global prevalence of depression and anxiety during the COVID-19 pandemic have been estimated to be 24% and 21% respectively, representing a concurrent epidemic, with public transportation closures the only mitigation measure found to be associated with increased anxiety  No  Full review  Other  Castaldelli-Maia JM, Marziali ME, Lu Z, Martins SS. Investigating the effect of national government physical distancing measures on depression and anxiety during the COVID-19 pandemic through meta-analysis and meta-regression. 2020. 
      2020-05-07
7/10  No  Low-to-moderate quality evidence showed that the potential negative effects of physical distancing on mental health are exacerbated by quarantine duration, infection fear, inadequate supplies, inadequate information, financial loss, and stigma [Review of syntheses and single studies conducted during the COVID-19 and pre-COVID-19 era] Yes (row content last updated on 2021-01-18) Rapid review Benefits and harms National Collaborating Centre for Methods and Tools. How does physical distancing impact mental health?. Hamilton: National Collaborating Centre for Methods and Tools; 2020. 
    Temporal distancing                
    Altering sexual activities
N/A (Protocol)  n/a  No  [Protocol - no results yet available] A systematic review to evaluate whether SARS-CoV-2 can be sexually transmitted is currently being conducted Yes (row content last updated on 2020-12-07) Protocol  Other  Duarte G, Ortiz-Muñoz L, Morales M, Rada G. Sexual Transmission of SARS-CoV-2 Virus, and its Role in the Spread of COVID-19: a Living Systematic Review Protocol. PROSPERO 2020; CRD42020189368. 
    Public-focused behaviour-change supports 2020-05-01
6/11 No People touch their faces as often as 50 times per hour, and their T-zone (eyes, nose, mouth and chin) as much as 68 times per hour, which requires extensive behaviour intervention and community awareness [Review of observational studies] No  Full review  Other  Rahman J. Mumin J. Fakhruddin B. How frequently do we touch facial T-zone: A systematic review. 2020;86(1):75. 
      Not specified
5/11  Yes  A rapid review found that public adherence to wearing face masks depends on several socio-behavioral factors, and that consistent and effective public messaging is key to supporting implementation  No  Rapid review  Other  The British Academy. Face masks and coverings for the general public: Behavioural knowledge, effectiveness of cloth coverings and public messaging. Oxford, UK: The British Academy. 2020;  
      2020-09-28
7/10  Yes  A review of communication strategies to mitigate risk behaviours found low to moderate evidence suggesting clear, action-oriented and tailored messages that are repeated frequently and delivered by trusted leaders probably improve risk communication, and that addressing uncertainty and previous errors in communication may help to build trust, while framing messages positively in relation to collective action rather than individual action is probably more effective Yes (row content last updated on 2021-01-18) Rapid review  Benefits and harms  National Collaborating Centre for Methods and Tools. Rapid review: What are best practices for risk communication and strategies to mitigate risk behaviours? National Collaborating Centre for Methods and Tools. 2020; 
    Health worker and essential worker-focused behaviour change supports for the above 2020-03-26 7/9 Yes The design and content of infection prevention and control guidelines, how they are communicated, and whether there is adequate organizational support, training, and access to personal protective equipment affects adherence among healthcare workers No Rapid review Other Houghton C, Meskell P, Delaney H, et al. Barriers and Facilitators to Healthcare Workers' Adherence with Infection Prevention and Control (IPC) Guidelines for Respiratory Infectious Diseases: a Rapid Qualitative Evidence Synthesis. Cochrane Database Syst Rev 2020;4(4):CD013582.
      2020-03-20
9/10  Yes  There is uncertainty about the effectiveness of procedures to prevent exposure to contaminated body fluids in health care workers, although providing donning and doffing instructions as well as using extra sanitation for doffing may reduce the risk of contamination  Yes (row content last updated on 2021-01-18) Full review  Benefits and harms  Verbeek J, Rajamaki B, Ijaz S, et al. Personal Protective Equipment for Preventing Highly Infectious Diseases due to Exposure to Contaminated Body Fluids in Healthcare Staff. Cochrane Database Syst Rev 2020;4(4):CD011621. 
    Other 2020-07-21
6/6  Yes  No completed studies were found that evaluated the effects of healthcare workers' use of antimicrobial mouthwash and nasal sprays to protect them when treating suspected COVID-19 patients No Full review Benefits and harms  Burton MJ, Clarkson JE, Goulao B, Glenny A-M, McBain AJ, Schilder AGM, et al. Use of antimicrobial mouthwashes (gargling) and nasal sprays by healthcare workers to protect them when treating patients with suspected or confirmed COVID‐19 infection. Cochrane Database of Systematic Reviews. 2020;(9):Art. No.: CD013626. DOI: 10.1002/14651858.CD013626.pub2. 
      2020-06-01
6/6  Yes  No completed studies were found that evaluated the effects of healthcare workers' use of antimicrobial mouthwash and nasal sprays to protect them when undertaking aerosol-generating procedures on suspected COVID-19 patients  No  Full review  Benefits and harms  Burton MJ, Clarkson JE, Goulao B, Glenny A-M, McBain AJ, Schilder AGM, et al. Antimicrobial mouthwashes (gargling) and nasal sprays to protect healthcare workers when undertaking aerosol‐generating procedures (AGPs) on patients without suspected or confirmed COVID‐19 infection. Cochrane Database of Systematic Reviews. 2020;(9):Art. No.: CD013628. DOI: 10.1002/14651858.CD013628.pub2.
  Service limitations (see relevant sector within economic and social responses)                
Infection control                
  Screening                
    Targets 2020-05-01  7/9  No  Study design, quality, and prevalence estimates of early SARS-CoV-2 serosurveys are heterogeneous (ranging from 0.4% to 59.3%), suggesting that the urgency to examine seroprevalence may have compromised methodological rigour
Yes (row content last updated on 2021-01-18) Rapid review  Other  Bobrovitz N, Arora R, Yan T, Rahim H, Duarte N, Bouher E, et al. Lessons from a Rapid Systematic Review of Early SARS-CoV-2 Serosurveys. MedRxiv 2020. 
      2020-04-27
8/10  No  No evidence is available regarding symptoms that can be used to determine if patients presenting to primary care have COVID-19, and evidence for patients presenting to outpatient clinics and emergency departments suggests there are no clear set of symptoms that can be used to indicate a COVID-19 infection
Yes (row content last updated on 2021-01-18) Full review Other Struyf T, Deeks JJ, Dinnes J, et al. Signs and symptoms to determine if a patient presenting in primary care or hospital outpatient settings has COVID-19 disease. Cochrane Database Syst Rev. 2020;7:CD013665. Published 2020 Jul 7. doi:10.1002/14651858.CD013665 
      2020-07-03
7/10  No  Despite substantial variation on the secondary attack rates, asymptomatic individuals were responsible for fewer secondary infections compared to symptomatic and pre-symptomatic individuals  Yes (row content last updated on 2021-01-18) Full review  Other  Qiu X, Nergiz AI, Maraolo AE, Bogoch II, Low N, Cevik M. Defining the role of asymptomatic SARS-CoV-2 transmission: A living systematic review. medRxiv. 2020. 
      2020-06-10
7/11  No  On average 20% of patients with SARS-CoV-2 remain asymptomatic through the course of infection, and these infections may have lower secondary attack rates compared to symptomatic infections and there is variability in the rate of presymptomatic infections [Review of observational studies] Yes (row content last updated on 2021-01-18) Full review Other Buitrago-Garcia D, Egli-Gany D, Counotte MJ, Hossmann S, Imeri H, Ipekci AM, et al. Occurrence and transmission potential of asymptomatic and presymptomatic SARS-CoV-2 infections: A living systematic review and meta-analysis. PLoS Medicine. 2020;17(9):e1003346. 
      2020-07-25
7/11  No  Secondary attack rates range from 16% to 21%, with higher rates in households and other residential settings and when infections are symptomatic [Review of observational studies] No  Full review  Other  Koh WC, Naing L, Chaw L, Rosledzana MA, Alikhan MF, Jamaludin SA, et al. What do we know about SARS-CoV-2 transmission? A systematic review and meta-analysis of the secondary attack rate and associated risk factors. medRxiv. 2020;15(10):e0240205. 
      2020-04-17
6/10  Yes  While no evidence was found on universal screening for SARS-CoV-2 infection, modelling studies suggest that screening at travel hubs may slightly slow the importation of infected cases  No  Rapid review  Benefits and harms  Viswanathan M, Kahwati L, Jahn B, Giger K, Dobrescu AI, Hill C, et al. Universal screening for SARS‐CoV‐2 infection: A rapid review. Cochrane Database of Systematic Reviews 2020, Issue 9. Art. No.: CD013718. DOI: 10.1002/14651858.CD013718. 
    Methods  2020-04-11
7/11  No  Most cases of COVID-19 in children and adolescents have a favourable clinical course, with the most prevalent clinical manifestations being fever and cough  No  Full review  Other  Mantovani A, Rinaldi E, Zusi C, Beatric G, Saccomani D, Dalbeni A. Coronavirus Disease 2019 (COVID-19) in Children and/or Adolescents: A Meta-Analysis. Pediatr Res 2020. 
      2020-04-30
9/11  No  Children over 12 months of age generally experience milder symptoms than adults, but younger children were more likely to experience critical illness and vomiting [Review of observational studies] No  Full review  Other Cui X, Zhao Z, Zhang T, Guo W, Guo W, Zheng J, et al. A systematic review and meta-analysis of children with coronavirus 2019 (COVID-19). Journal of medical virology. 2020. 
      2020-05-29
9/11  No Non-contact infrared thermometers and thermal scanners may have reasonable sensitivity and specificity for diagnosing fever, but the sensitivity of thermal scanners decreased in the context of pandemics [Review of studies conducted during the COVID-19, H1N1, seasonal influenza and SARS outbreaks] No  Full review  Test accuracy  Aggarwal N, Garg M, Dwarakanathan V, Gautam N, Kumar SS, Jadon RS, et al. Diagnostic accuracy of non-contact infrared thermometers and thermal scanners: A systematic review and meta-analysis. Journal of Travel Medicine. 2020. 
      2020-04-17
6/10  Yes  The certainty of the evidence is low or very low for the accuracy of different universal screening methods, but in general they are shown to have low sensitivity  No  Rapid review  Test accuracy  Viswanathan M, Kahwati L, Jahn B, Giger K, Dobrescu AI, Hill C, et al. Universal screening for SARS‐CoV‐2 infection: A rapid review. Cochrane Database of Systematic Reviews 2020, Issue 9. Art. No.: CD013718. DOI: 10.1002/14651858.CD013718. 
    Locations (and frequency if applicable) 2020-06-26
8/9  Yes  This rapid review found insufficient real-world evidence to determine the effects of travel related measures to contain the COVID-19 pandemic, although some studies from the pre-COVID era found screening at borders as a possible approach for detecting infected travellers   No  Rapid review  Benefits and harms  Burns J, Movsisyan A, Stratil JM, Coenen M, Emmert-Fees KMF, Geffert K, et al. Travel‐related control measures to contain the COVID‐19 pandemic: A rapid review. Cochrane Database of Systematic Reviews.2020;(9):Art. No.: CD013717. DOI: 10.1002/14651858.CD013717. 
      2020-05-22
4/10  No  Insufficient evidence to assess the effectiveness of workplace screening programs for reducing the spread of COVID-19 was found in healthcare settings, but some evidence suggests that multifaceted strategies are most likely to be effective in detecting staff illness [Review of studies mainly conducted during the pre-COVID-19 era] No  Rapid review  Benefits and harms  Erdmann R. Rapid review: Effectiveness of workplace screening programs for reducing the spread of COVID-19 in healthcare settings. Edmonton, AB: Alberta Health Services, COVID-19 Scientific Advisory Group; 2020. 
  Quarantining of exposed or potentially exposed individuals                
    Voluntary or imposed 2020-04-01 9/11 No One randomized controlled trial has found that quarantining workers during an epidemic when members of their household are infected can control the spread of influenza-like-illness, but increases their individual risk of infection
No Full review Benefits and harms Jefferson T, Jones M, Al Ansari L, Bawazeer G, Beller E, Clark J, et al. Physical Interventions to Interrupt or Reduce the Spread of Respiratory Viruses. Part I - Face Masks, Eye Protection and Person Distancing: Systematic Review and Meta-Analysis. MedRxiv 2020.
      2020-06-23 7/10  Yes  Evidence of how effective quarantines are alone or in combination with other measures for people who were in contact with a confirmed/suspected case of COVID-19 mostly comes from mathematical modelling studies, which consistently show that they can be important for reducing COVID-19 incidence and mortality Yes (row content last updated on 2021-01-18) Rapid review  Other  Nussbaumer-Streit B, Mayr V, Dobrescu AIulia, Chapman A, Persad E, Klerings I, et al. Quarantine alone or in combination with other public health measures to control COVID‐19: A rapid review. Cochrane Database of Systematic Reviews. 2020;(4)CD013574. 
      2020-06-26
8/9  Yes  The effectiveness of quarantining travellers is uncertain  No  Rapid review  Benefits and harms  Burns J, Movsisyan A, Stratil JM, Coenen M, Emmert-Fees KMF, Geffert K, et al. Travel‐related control measures to contain the COVID‐19 pandemic: A rapid review. Cochrane Database of Systematic Reviews.2020;(9):Art. No.: CD013717. DOI: 10.1002/14651858.CD013717. 
      2020-06-02
5/9  No  Whereas the majority of jurisdictions explored require a 14-day quarantine for people exposed to COVID-19, there is important variability in the duration of quarantine from symptoms onset, and after having ended symptoms  No  Full review  Other  National Collaborating Centre for Methods and Tools. Rapid Review: Are any jurisdictions using isolation periods other than 14 days in response to COVID-19?. Hamilton, ON: National Collaborating Centre for Methods and Tools; 2020. 
  Testing                
    Priority individuals (including their contacts) 2020-06-15
5/9  No  Although existing evidence suggests there is heterogeneity in the secondary attack rate of COVID-19 within households, compared to other contacts, individuals living with a positive COVID-19 case are at greater risk of infection
No  Full review Other Shah K, Saxena D, Mavalankar D. Secondary attack rate of COVID-19 in household contacts: Systematic review. QJM. 2020;hcaa232. 
      2020-05-01
6/11  No  The incidence of positive RT-PCR and abnormal computed tomography tests were higher than 92% among pregnant women with SARS-CoV-2 infection, and fever and cough were the most common symptoms  No  Full review  Other  Uygun-Can B & Acar-Bolat B. Clinical properties and diagnostic methods of COVID-19 infection in pregnancies: Meta-analysis. BioMed Research International. 2020. 
    Methods (including performance and quality assurance)
2020-04-01  8/11 No  [All tests] RT-PCR using sputum samples is the most sensitive method to diagnose COVID-19, followed by the use of CT scan, with a general observation that respiratory samples are more sensitive regardless of the analysis technique used  No Full review  Test accuracy  Böger B, Fachi MM, Vilhena RO, Cobre AF, Tonin FS, Pontarolo R. Systematic review with meta-analysis of the accuracy of diagnostic tests for COVID-19 [published online ahead of print, 2020 Jul 10]. Am J Infect Control. 2020;S0196-6553(20)30693-3. doi:10.1016/j.ajic.2020.07.011 
      2020-05-04
4/10  No  [All tests] The body part sampled and timing of test relative to symptom onset might influence the accuracy of RT-PCR tests, but there is a lack of studies evaluating the test accuracy of RT-PCR [Review mainly based on low quality studies] Yes (row content last updated on 2021-01-18) Rapid review  Test accuracy  Health Technology Wales. The clinical effectiveness of tests to detect the presence of SARS-CoV-2 virus, and antibodies to SARS-CoV-2, to inform COVID-19 diagnosis. Cardiff, UK: Health Technology Wales, 2020. 
      2020-04-27
11/11  No  [Antibody testing] Antibody testing may be an appropriate approach for detecting previous SARS-CoV-2 infection when taken 15 days after symptom onset, with uncertainty remaining about their application beyond 35 days after symptom onset  No Full review  Test accuracy  Deeks JJ, Dinnes J, Takwoingi Y, Davenport C, Spijker R, Taylor-Phillips S, et al. Antibody tests for identification of current and past infection with SARS-CoV-2. Cochrane Database Syst Rev. 2020 Jun 25;  
      2020-06-07  7/10  Yes  [CT scan] The sensitivity of using chest computed tomography to diagnose SARS-CoV-2 infection was found to be similar to using RT-PCR, particularly in symptomatic patients, but there is a lack of evidence about its use for diagnosing asymptomatic patients
No Full review  Test accuracy  Shao, J.M., Ayuso, S.A., Deerenberg, E.B., Elhage, S.A., Augenstein, V. and Heniford, B.T. (2020), A Systematic Review of CT Chest in COVID‐19 Diagnosis and its Potential Application in a Surgical Setting. Colorectal Dis. Accepted Author Manuscript. doi:10.1111/codi.15252 
      2020-04-03
7/11  No  [CT scan] While the sensitivity of both chest CT and reverse transcriptase PCR were both high, the pooled specificity for chest CT was only 37%. Hence the use of CT scan as a screening tool to identify patients with COVID-19 is substantially impaired, particularly in low prevalence regions No  Full review  Test accuracy  Kim H, Hong H, Yoon S. Diagnostic performance of CT and reverse transcriptase-polymerase chain reaction for Coronavirus Disease 2019: A meta-analysis. Radiology. 2020. 
      2020-06-22 9/11 No [CT scan] While important heterogeneity among studies was found, available evidence suggests that chest CT scan is sensitive but has moderate specificity [Review mainly based on low quality studies]
Yes (row content last updated on 2021-01-18) Full review  Test accuracy  Salameh J-P, Leeflang MMG, Hooft L, Islam N, McGrath TA, Pol CB, et al. Thoracic imaging tests for the diagnosis of COVID‐19. Cochrane Database of Systematic Reviews. 2020;9:Art. No.: CD013639. DOI: 10.1002/14651858.CD013639.pub3.
      2020-04-16
8/11  No  [CT scan] While the sensitivity of CT scan for detecting SARS-CoV-2 infections appears high, the specificity of this test on suspected cases remains low compared to RT-PCR  No  Full review  Test accuracy  Li K, Wu X, Zhong Y, Qin W, Zhang Z. Diagnostic performance of CT and its key signs for COVID-19: A systematic review and meta-analysis. medRxiv. 2020.  
      2020-04-25
6/11  No  [Lung ultrasound] Lung ultrasound can be a contributor to diagnosing COVID-19, but not to confidently rule out the disease
No  Full review  Test accuracy  Mohamed MFH, Al-Shokri S, Yousaf Z, et al. Frequency of Abnormalities Detected by Point-of-Care Lung Ultrasound in Symptomatic COVID-19 Patients: Systematic Review and Meta-Analysis. Am J Trop Med Hyg. 2020.  
      2020-06-22
9/11  No  [Lung ultrasound] A review of thoracic imaging tests found that the quality of the existing primary research precludes firm conclusions around the accuracy of  lung ultrasound Yes (row content last updated on 2021-01-18) Full review  Test accuracy  Salameh J-P, Leeflang MMG, Hooft L, Islam N, McGrath TA, Pol CB, et al. Thoracic imaging tests for the diagnosis of COVID‐19. Cochrane Database of Systematic Reviews. 2020;9:Art. No.: CD013639. DOI: 10.1002/14651858.CD013639.pub3.
   
2020-04-06 8/10 Yes [RT-PCR] The false-negative (patients incorrectly diagnosed as not having COVID-19) rate of patients undergoing RT-PCR tests is uncertain, hence repeat testing is necessary where the diagnosis is in doubt
Yes (row content last updated on 2021-01-18) Full review Test accuracy Arevalo-Rodriguez I, Buitrago-Garcia D, Simancas-Racines D, Zambrano-Achig P, del Campo R, Ciapponi A. False-Negative Results of Initial RT-PCR Assays for COVID-19: A Systematic Review. MedRxiv 2020.
      2020-06-22 9/11  No  [X-ray] A review of thoracic imaging tests found that the quality of the existing primary research precludes firm conclusions around the accuracy of chest-X-rays
Yes (row content last updated on 2021-01-18) Full review Test accuracy Salameh J-P, Leeflang MMG, Hooft L, Islam N, McGrath TA, Pol CB, et al. Thoracic imaging tests for the diagnosis of COVID‐19. Cochrane Database of Systematic Reviews. 2020;9:Art. No.: CD013639. DOI: 10.1002/14651858.CD013639.pub3.
      2020-04-19
7/10  No  In children with SARS-CoV-2 infection, viral shedding samples have been found to be present for longer in feces compared to the respiratory tract. This may be of relevance in relation to different possible routes of transmission
No  Full review Other Santos VS, Gurgel RQ, Cuevas LE, Martins-Filho PR. Prolonged fecal shedding of SARS-CoV-2 in pediatric patients. A quantitative evidence synthesis [published online ahead of print, 2020 May 22]. J Pediatr Gastroenterol Nutr. 2020;10.1097/MPG.0000000000002798. doi:10.1097/MPG.0000000000002798 
      2020-04-30
8/11  No  The diagnostic accuracy of serological tests for COVID-19 is uncertain  No Full review Test accuracy Lisboa Bastos M, Tavaziva G, Abidi SK, Campbell JR, Haraoui LP, Johnston JC, et al. Diagnostic accuracy of serological tests for covid-19: Systematic review and meta-analysis. BMJ. 2020. 
      2020-04-25
7/11  No  The sensitivity of saliva-based tests is comparable to nasopharyngeal-swab tests, but there was very limited data on specificity
No  Full review  Test accuracy  Czumbel LM, Kiss S, Farkas N, Mandel I, Hegyi AE, Nagy AK, et al. Saliva as a candidate for COVID-19 diagnostic testing: A meta-analysis. medRxiv. 2020. 
      2020-05-02
8/11  No  Although the sensitivity of serologic-based to detect either present or past infection are around 80%, its performance is still highly dependant on the prevalence of COVID-19 No  Full review  Test accuracy  de Moura DTH, McCarty TR, Ribeiro IB, Funari MP, de Oliveira PVAG, de Miranda Neto AA, et al. Diagnostic characteristics of serological-based COVID-19 testing: A systematic review and meta-analysis. Clinics. 2020;75:e2212. 
      Not specified
8/11  No  In people with severe acute respiratory syndrome caused by SARS-Cov-2, lower respiratory tract samples (especially bronchoalveolar lavaga fluid) and rectal specimens were the most likely to test positive, whereas nasopharyngeal swabs had a positive rate of less then 50% and the virus was not detected in urogenital specimens using RT PCR  No  Full review  Other  Bwire GM, Majigo MV, Njiro BJ, Mawazo A. Detection profile of SARS-CoV-2 using RT-PCR in different types of clinical specimens: A systematic review and meta-analysis. Journal of medical virology. 2020. 
      2020-04-30
6/10  No  The likelihood of a positive SARS-CoV-2 test using a respiratory sample decreases with time from symptoms onset, with sputum specimens showing the highest positivity rates, and oropharyngeal swabs the lowest  No  Full review  Other  Mohammadi A, Esmaeilzadeh E, Li Y, Bosch RJ, Li J. SARS-CoV-2 detection in different respiratory sites: A systematic review and meta-analysis. Medrxiv. 2020.
      2020-08-04
7/9  No  Evidence suggests a relationship between the time from collection of a specimen, copy threshold, and symptom severity when doing SARS-CoV-2 culture, and also suggests that a positive PCR test in isolation may not imply infectivity [Review mainly based on low quality studies]  Yes (row content last updated on 2021-01-18) Full review  Other  Jefferson T, Spencer E, Brassey J, Heneghan C, et al. Viral cultures for COVID-19 infectivity assessment. Systematic review. medRxiv 2020. 
      Not specified
8/11  No  Lower respiratory tract specimens appear to be best for detecting SARS-CoV-2 infection, with bronchalveolar lavage fluids offering the highest positivity rate, whereas the virus can also be detected to varying degrees of success using rectal swabs, sputum, nasopharyngeal and oropharyngeal swabs, but cannot be detected successfully from urinogenital samples  No  Full review  Other  Bwire GM, Majigo MV, Njiro BJ, Mawazo A. Profiling the positive detection rate of SARS-CoV-2 using polymerase chain reaction in different types of clinical specimens: A systematic review and meta-analysis. medRxiv. 2020. 
      2020-06-01
7/11  No  Low prevalence of ocular manifestations of COVID-19 was found and a very low PCR positivity rate on ocular samples [Review of observational studies] No  Full review  Test accuracy  La Distia Nora R, Putera I, Khalisha DF, Septiana I, Ridwan AS, Sitompul R. Are eyes the windows to COVID-19? Systematic review and meta-analysis. BMJ Open Ophthalmology. 2020;5(1). 
    Locations (and frequency if applicable)                
    Speeding results 2020-04-13
8/11 No There is no strong evidence to accurately indicate the sensitivity and specificity for available rapid point-of-care COVID-19 diagnostic tests  No  Full review  Test accuracy  Ricco M, Ferraro P, Gualerzi G, et al. Point-of-Care Diagnostic Tests for Detecting SARS-CoV-2 Antibodies: A Systematic Review and Meta-Analysis of Real-World Data. J Clin Med 2020 May 18;9(5). 
      2020-05-25
9/11  No  Important heterogeneity in the diagnostic accuracy of point-of-care antigen and molecular tests to diagnose SARS-CoV-2 infection was found [Review mainly based on low or unclear quality studies] Yes (row content last updated on 2021-01-18) Full review  Test accuracy  Dinnes J, Deeks JJ, Adriano A, Berhane S, Davenport C, Dittrich S, et al. Rapid, point‐of‐care antigen and molecular‐based tests for diagnosis of SARS‐CoV‐2 infection. Cochrane Database of Systematic Reviews. 2020;(8):Art. No.: CD013705. DOI: 10.1002/14651858.CD013705. 
      2020-06-27
4/9  No  Machine learning techniques to analyze chest CT and X-ray images might be able to accurately detect the presence of COVID-19 [Review mainly based on studies of unknown quality] No  Full review  Other  Syeda HB, Syed M, Sexton KW, et al. The Role of Machine Learning Techniques to Tackle COVID-19 Crisis: A Systematic Review. medRxiv 2020. 
  Isolation of suspected or confirmed cases 2020-08-26
6/10  No  COVID-19 patients with mild-to-moderate illness are unlikely to be infectious after 10 days from symptom onset, whereas severe or immunocompromised patients may remain infectious for longer than 10 days [Review including studies of variable quality]
No Full review  Other  Walsh KA, Spillane S, Comber L, Cardwell K, Harrington P, Connell J, et al. The duration of infectiousness of individuals infected with SARS-CoV-2. Journal of Infection. 2020.  
  Contact tracing 2020-05-05
10/10  Yes  Digital contact tracing technologies used alongside manual methods and other public-health measures such as isolation may successfully identify secondary cases and could save time, but there is limited evidence about their effectiveness, acceptability and implementation in real-world outbreak settings  No Rapid review Benefits and harms  Anglemyer A, Moore THM, Parker L, Chambers T, Grady A, Chiu K, et al. Digital contact tracing technologies in epidemics: A rapid review. Cochrane Database of Systematic Reviews 2020, Issue 8. Art. No.: CD013699. DOI: 10.1002/14651858.CD013699 
    2020-04-30
6/9  No  A systematic review found no empirical studies comparing automated with manual contact tracing systems for COVID-19 or other infectious diseases, but modelling studies suggest that the effectiveness of contact tracing depends on disease context, timeliness of case identification and notification, tracers' expertise, case and contact definitions, and behavioral factors No  Full review  Benefits and harms  Braithwaite I, Callender T, Bullock M, Aldridge RW. Automated and partly automated contact tracing: A systematic review to inform the control of COVID-19. The Lancet Digital Health. 2020;2(11):e607-e621.  
  Susceptibility tracking                
    Antibody testing 2020-05-01
7/9  No  Existing studies suggest urgency to examine seroprevalence may have compromised methodological rigour, restricting the conclusions that can be drawn about the link between prevalence and immunity to COVID-19
Yes (row content last updated on 2021-01-18) Rapid review  Other  Bobrovitz N, Arora R, Yan T, Rahim H, Duarte N, Bouher E, et al. Lessons from a Rapid Systematic Review of Early SARS-CoV-2 Serosurveys. MedRxiv 2020. 
      2020-04-27
11/11  No  Antibody testing appears to be a potentially appropriate approach for detecting previous SARS-CoV-2 infection when taken 15 days after symptom onset, with uncertainty remaining about their application beyond 35 days after symptom onset  No  Full review  Test accuracy  Deeks JJ, Dinnes J, Takwoingi Y, Davenport C, Spijker R, Taylor-Phillips S, et al. Antibody tests for identification of current and past infection with SARS-CoV-2. Cochrane Database Syst Rev. 2020 Jun 25;  
      2020-07-06
5/9  No  The immunity response following infection with COVID-19 is not yet known, the presence of antibody response was consistently reported, but the probability of reinfection can't be ruled out
Yes (row content last updated on 2021-01-18) Full review  Other  Health Information and Quality Authority, Ireland. Evidence summary of immunity response following infection with COVID-19. Cork, Ireland: Health Information and Quality Authority, Ireland; 2020. 
      N/A (Protocol)
n/a  No  [Protocol - no results yet available] A systematic review on seroprevalence surveys from around the world is currently being conducted  Yes (row content last updated on 2020-12-07) Protocol  Other  Bobrovitz N, Arora R, Boucher E, Yan T, Rahim H, Van Wyk J, et al. A Living Rapid Systematic Review of SARS-CoV-2 Seroprevalence Studies. PROSPERO 2020; CRD42020183634. 
      2020-08-14
7/11  No  A meta-analysis showed that pooled global SARS-CoV-2 seroprevalence varied substantially across regions and countries (between 0.37% and 22.1%)  No  Full review  Other  Rostami A, Sepidarkish M, Leeflang M, Riahi SM, Shiadeh MN, Esfandyari S, et al. First snap-shot meta-analysis to estimate the prevalence of serum antibodies to SARS-CoV-2 in humans. medRxiv. 2020. 
      2020-04-04
9/11  Yes  FDA authorized serology tests to detect SARS-CoV-2 antibodies probably have a high sensitivity and specificity, but their diagnostic accuracy is optimal 15 or more days post symptom onset No  Full review  Test accuracy  Rajesh P & Anand G. Diagnostic accuracy of FDA authorized serology tests to detect SARS-CoV-2 antibodies: A systematic review and meta-analysis. medRxiv. 2020.  
      2020-09-18
7/9  Yes  The potential for COVID-19 re-infection and for new transmission after recovery is currently uncertain  Yes (row content last updated on 2021-01-18) Rapid review  Other  National Collaborating Centre for Methods and Tools. Rapid Review Update 3: What is known on the potential for COVID-19 re-infection, including new transmission after recovery? Hamilton, ON: National Collaborating Centre for Methods and Tools; 2020. 
      2020-05-04
4/10 No Extensive variability in the sensitivity estimates across tests used to detect antibodies to SARS-CoV-2 was found [Review mainly based on low quality studies]
Yes (row content last updated on 2021-01-18) Rapid review Test accuracy  Health Technology Wales. The clinical effectiveness of tests to detect the presence of SARS-CoV-2 virus, and antibodies to SARS-CoV-2, to inform COVID-19 diagnosis. Cardiff, UK: Health Technology Wales, 2020. 
    Antibody test usage                
Broader public-health measures                
  Risk stratification                
    Stratifying the population by risk of infection  2020-06-15
5/9  No  Although existing evidence suggests there is heterogeneity in the secondary attack rate of COVID-19 within households,  compared to other contacts, individuals living with a positive COVID-19 care are at greater risk of infection  No Full review  Other  Shah K, Saxena D, Mavalankar D. Secondary attack rate of COVID-19 in household contacts: Systematic review. QJM. 2020;hcaa232. 
      N/A (Protocol)
n/a  No  [Protocol - no results yet available] A systematic review to explore the association between demographic factors and a COVID-19 diagnosis in patients is currently being conducted  Yes (row content last updated on 2020-12-07) Protocol  Other  Atherley A, Derckx R, Dijkstra J, Franssen G, Hendriks S, Jolani S, et al. Demographic Factors and COVID-19: a Rapid and Living Systematic Review and Meta-Analysis. PROSPERO 2020; CRD42020180085. 
      N/A (Protocol)
n/a  No  [Protocol - no results yet available] A systematic review to explore the association between lifestyle factors and a COVID-19 diagnosis is currently being conducted  Yes (row content last updated on 2020-12-07) Protocol  Other  Wesselius A, der Ven E, Bongaerts B, Dijksma I, Ament S, Falahi F, et al. Lifestyle Factors and COVID-19: a Rapid and Living Systematic Review and Meta-Analysis. PROSPERO 2020; CRD42020181902. 
      2020-07-08
7/11  No  Healthcare workers, particularly nurses, report a high prevalence of SARS-CoV-2 infection, with a significant proportion of asymptomatic or pre-symptomatic carriers  Yes (row content last updated on 2021-01-18) Full review  Other  Gómez-Ochoa SA, Franco OH, Rojas LZ, Raguindin PF, Roa-Diaz ZM, Wyssmann BM, et al. COVID-19 in healthcare workers: A living systematic review and meta-analysis of prevalence, risk factors, clinical characteristics, and outcomes. American Journal of Epidemiology. 2020. 
      2020-08-25
6/11  No  The relationship between smoking status and infection, hospitalisation and mortality is uncertain. Current smokers may be at reduced risk of infection compared with non smokers, but they and former smokers may have an increased risk of hospitalisation and greater disease severity [Review of observational studies] Yes (row content last updated on 2021-01-18) Rapid review Other  Simons D, Shahab L, Brown J, Perski O. The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 7). Addiction. 2020. 
  Outbreak management                
    Locations (essential services or other) 2020-06-26 7/10 Yes Outbreak investigations show that long-term care facilities are more vulnerable to the COVID-19 pandemic, in terms of disease spread and mortality rate
Yes (row content last updated on 2021-01-18) Full review Other Salcher-Konrad M, Jhass A, Naci H, Tan M, El-Tawil Y, Comas-Herrera A. COVID-19 Related Mortality and Spread of Disease in Long-Term Care: First Findings from a Living Systematic Review of Emerging Evidence. MedRxiv 2020.
      2020-10-05
8/10  Yes  The incidence in the surrounding community is probably associated with COVID-19 outbreaks in long-term care settings, while increased staff (particularly registered nurse staff) may be associated with a reduced risk of COVID-19 outbreaks, and for-profit status and facility size may increase the risk of COVID-19 outbreaks  No  Rapid review  Other  National Collaborating Centre for Methods and Tools. (2020, October 16). What risk factors are associated with COVID-19 outbreaks and mortality in long-term care facilities and what strategies mitigate risk? 
  Pandemic tracking                
    Levels of re-emergence that trigger action                
  Vaccination                
    Vaccines to prevent other infections                
Future possible public-health measures                
  Vaccination (susceptibility reduction)                
    Supporting discovery of a vaccine to prevent COVID-19 (followed by its production, distribution, administration)                
    Choosing the best available vaccine to prevent COVID-19
               

* This topic has been the focus of extensive academic debate (see here), and the evidence is frequently being updated

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