key: cord-0847442-14gv311z
authors: Yang Chan, Emily Ying; Shahzada, Tayyab Salim; Sham, Tiffany Sze Tung; Dubois, Caroline; Huang, Zhe; Liu, Sida; Ho, Janice Ying-en; Hung, Kevin K C; Kwok, Kin On; Shaw, Rajib
title: Narrative review of non-pharmaceutical behavioural measures for the prevention of COVID-19 (SARS-CoV-2) based on the Health-EDRM framework
date: 2020-10-08
journal: Br Med Bull
DOI: 10.1093/bmb/ldaa030
sha: 069d82a27bc4da30decb78882f9d8c97f425179d
doc_id: 847442
cord_uid: 14gv311z

INTRODUCTION: Non-pharmaceutical measures to facilitate a response to the COVID-19 pandemic, a disease caused by novel coronavirus SARS-CoV-2, are urgently needed. Using the World Health Organization (WHO) health emergency and disaster risk management (health-EDRM) framework, behavioural measures for droplet-borne communicable diseases and their enabling and limiting factors at various implementation levels were evaluated. SOURCES OF DATA: Keyword search was conducted in PubMed, Google Scholar, Embase, Medline, Science Direct, WHO and CDC online publication databases. Using the Oxford Centre for Evidence-Based Medicine review criteria, 10 bottom-up, non-pharmaceutical prevention measures from 104 English-language articles, which published between January 2000 and May 2020, were identified and examined. AREAS OF AGREEMENT: Evidence-guided behavioural measures against transmission of COVID-19 in global at-risk communities were identified, including regular handwashing, wearing face masks and avoiding crowds and gatherings. AREAS OF CONCERN: Strong evidence-based systematic behavioural studies for COVID-19 prevention are lacking. GROWING POINTS: Very limited research publications are available for non-pharmaceutical measures to facilitate pandemic response. AREAS TIMELY FOR RESEARCH: Research with strong implementation feasibility that targets resource-poor settings with low baseline health-EDRM capacity is urgently needed.

Uncertainties in disease epidemiology, treatment and management in biological hazards have often urged policy makers and community health protection agencies to revisit prevention approaches to maximize infection control and protection. The COVID-19 pandemic, a disease caused by novel coronavirus SARS-CoV-2, has pushed global governments and communities to revisit the appropriate non-pharmaceutical health prevention measures in response to this unexpected virus outbreak. 1 The World Health Organization (WHO) health emergency and disaster risk management (health-EDRM) framework refers to the structured analysis and management of health risks brought upon by emergencies and disasters and was developed based on the Sendai Framework for Disaster Risk Reduction 2015-2030. The framework focuses on prevention and risk mitigation through hazard and vulnerability reduction, preparedness, response and recovery measures 2 and further calls attention to the significance of community involvement to counteract the potential negative impacts of hazardous events such as infectious disease outbreaks. 2 While the framework does not provide details on event-specific prevention, it is well justified for primary prevention measures against COVID-19, which is defined as a biological hazard under the health-EDRM disaster classification. 3 While there is evidence for potential COVID-19 droplet transmission, 4 the WHO has suggested that airborne transmission may only be possible in certain circumstances 4 and further evidence is needed to categorize it as an airborne disease specifically.

Health-EDRM prevention measures can be classified into primary, secondary or tertiary levels. 5 Primary prevention mitigates the occurrence of illness through an emphasis on health promotion and education aimed at behavioural modification 6 ; secondary prevention involves screening and infection identification; tertiary prevention focuses on treatment. In the context of COVID-19, both secondary and tertiary preventive measures are complicated due to the high incidence of asymptomatic patients, 7 the lack of consensus and availability of specific treatment or vaccine 8 and the added stress on the health system during a pandemic. Primary prevention that focuses on protecting an individual from contracting an infection 9 is therefore the most practical option. A comprehensive disaster management cycle (prevention, mitigation, preparedness, response and recovery) encompasses both top-down and bottom-up measures. 10, 11 Topdown measures require well-driven bottom-up initiatives to successfully achieve primary prevention and effectively modify community behaviours. 12 During and since the writing of this review, several landmark publications have studied and addressed the effect of non-pharmaceutical behavioural measures in preventing the transmission of COVID-19, generally concluding that while effectiveness and uptake of measures varied, behavioural change at personal and population levels is key to effectively control the spread of COVID-19. 13 -17 The purpose of this narrative review is to highlight the feasibility of implementing non-pharmaceutical preventive measures within a population facing an emergency, building on the health-EDRM framework, and theoretical aspects of behavioural change presented in other publications.

Based on the health-EDRM framework, which emphasizes the impact of context on efficacy of measure practices, 3 this article examines available published evidence on behavioural measures that might be adopted at the personal, household and community levels for droplet-borne transmitted diseases and enabling and limiting factors for each measure. Additionally, this article reviews the strength of available scientific evidence for each of the behavioural changes, which may reduce health risks.

A literature search was conducted in May 2020. English language-based literature published between January 2000 and May 2020 were identified and included. Further literature was identified using the references of those already reviewed. Types of literature include international peer-reviewed articles, online reports, commentaries, editorials, electronic books and press releases from universities and research institutions, which include expert opinions. Grey literature published by the WHO, the US Centers for Disease Control and Prevention (CDC) and other local government publications and information outlets were also included. Literature that did not fulfil the criteria was excluded, for example peer-reviewed studies without English-language abstracts.

Research databases examined in this study included PubMed, Google Scholar, Embase, Medline and Science Direct. The keywords and phrases included in the initial search can be broadly categorized into three groups: those relating to the virus, including variations of COVID-19 nomenclature, or relevant to broader respiratory viruses (such as 'COVID-19', 'SARS', 'enveloped viruses'); those relating to general disease prevention and management (such as 'transmission', 'risk management') and those relating to primary prevention measures (such as 'handwashing', 'coughing and sneezing', 'face masks'). The full list can be found in Appendix 1. Behavioural measures as well as risk factors for infectious disease transmission were reviewed in order to generate 10 common preventive measures for discussion. The avoidance of cutlery sharing, for example, was generated after determining it as a highly preventable risk for infectious disease transmission. Each primary prevention measure was summarized narratively according to the risk factors, co-benefits, enabling and limiting factors and strength of evidence. Three reviewers assessed the studies independently and agreed on the final research used.

The literature was categorized according to the Oxford Centre for Evidence-Based Medicine Levels of Evidence (Fig. 1) , 18 which systemizes strength of evidence into levels, based on the process of study design and methodology. Three reviewers collectively engaged in and agreed on the final categorization.

No new data were generated or analysed in support of this review. 

The search identified 104 relevant publications, all of which were reviewed and included in the results analysis. The search identified and grouped 10 common bottom-up, non-pharmaceutical, primary prevention behavioural measures, based on the health-EDRM framework. The review of evidence is disaggregated into the 10 prevention measures.

Six 'personal' protective practices (engage in regular handwashing, wear face mask, avoid touching the face, cover mouth and nose when coughing and sneezing, bring personal utensils when dining out and close toilet cover when flushing), two 'household' practices (disinfect household surfaces and avoid sharing cutlery) and two 'community' practices (avoid crowds and mass gatherings and avoid travel) were identified. Tables 1-3 highlight the potential health risk, desired behavioural changes, potential health co-benefits, enabling and limiting factors and strength of evidence available in published literature with regard to these measures.

Of note, a number of the reviewed articles report an assessment of more than one primary prevention measure. The review results showed that ∼68% of the studied literature was associated with personal practices, 13% with household practices and 19% with community practices. The measures of engaging in regular handwashing, wearing face masks as well as avoiding mass gatherings were among the most commonly studied preventive measures. Details of each utilized reference can be found in Appendix 2.

Evidence relating to 10 common health-EDRM behavioural measures for primary prevention against droplet-borne biological hazards were identified and reviewed. The information referenced here is based on best available evidence and will need to be updated as new studies and guidelines are published, and the understanding of the scientific community is enhanced. At the time of writing, there is an outstanding question as to whether COVID-19 is transmitted through droplet or aerosol in the community. Following the writing of this review, certain areas of evidence have evolved. On June 5, 2020, the WHO updated its official guidance to recommend that face masks be worn by the general public as a preventive measure against COVID-19 transmission. 122 The WHO had previously recommended that masks be worn only by healthcare workers and people confirmed to have COVID-19, due to limited evidence that masks worn by health individuals may be effective as a prevention measure. 123 The knowledge and consensus within the scientific community on COVID-19 continue to evolve at an unprecedented rate. • Alcohol-based formulas as an alternative; efficacy in killing enveloped viruses has been demonstrated 65

• Use of ash and mud as an alternative in areas where there is no access to soap or alcohol-based rubs. Although these carry potential antimicrobial properties, 66 their efficacy in counteracting viral infections is not well-evidenced 67

• Sharing and reusing water or water containers, in areas lacking running water, elevate the risk of transmission through droplets.

• For those who cannot access surgical face masks, due to affordability, availability or otherwise, homemade masks 69 accompanied with the same hygienic measures can be considered 70

• Where face touching is necessary or difficult to control, for example in infants or children, handwashing will be a more effective prevention measure Continued • The proximity and contact with individuals heighten the evidenced risk of taking in potential respiratory droplets containing COVID-19 from others

• There is no clear evidence regarding increased risk from aeroplane travel specifically Although direct evidence on the efficacy of COVID-19-specific prevention measures is lacking, largely due to the novelty of the disease, five behavioural measures were identified: regular handwashing, wearing face masks, avoiding touching of face, covering during sneezing or coughing and household disinfecting. Five other potential behavioural measures were also identified through logical deductions from potential behavioural risks associated with transmission of diseases similar to COVID-19. 79 Utensil-related practices, in particular, were heavily limited in evidence to support their efficacy against viral infections.

The efficacy and success of the 10 bottom-up behavioural measures reviewed here are subject to specific enabling and limiting determinants, ranging from demographic (e.g. age, gender, education), socio-cultural, economic (e.g. financial accessibility to commodities) and knowledge (e.g. understanding of risk, equipment use). The viability and efficacy of each measure may be limited by determinants and constraints in different contexts. Resource-deprived areas may face constraints and reduced effectiveness of implementation, especially for measures that require preventive commodities such as face masks and household disinfectants. As such, special attention should be given to rural settings, informal settlements and resource-deficit contexts where access to information and resources such as clean water supply are often limited, 124,125 and sanitation facilities are lacking. 126 For hygiene measures, different alternatives should be promoted and their relative scientific merits should be evaluated, such as the use of ash as an alternative to soap for handwashing 67 or the efficacy of handwashing with alcohol sanitizer, which has been demonstrated in previously published studies for H1N1 127 and noroviruses 128 but not yet concretely for COVID-19. Meanwhile, for measures that have no direct alternatives available, it is important for authorities and policymakers to understand the capacity limitations of certain target groups and provide additional support or put in place other preventive measures. In cases where material resources are scarce, the measures of awareness on sneezing and coughing etiquette as well as avoiding hand-to-face contact are the most convenient to adopt as they require little to no commodities. However, it should be well noted that these measures are likely the most challenging in compliance and enforceability, as they rely on the modification of frequent and natural human behaviours whose modifications would require awareness and practice. 50,51 Furthermore, these can be challenging to implement in target groups with less capacity for health literacy and translation of education into practice, such as infants and elderly suffering from dementia. Cultural patterns can be associated with behavioural intentions. In the case of avoiding utensil-sharing during meals, enforcing change may be conflicted with cultural and traditional norms in Asia and certain European communities. 129 Of the enabling factors documented for each proposed measure, shared enablers can be identified: accessibility and affordability of resources; related knowledge, awareness and understanding of risk; and associated top-down policy facilitation.

Majority of personal and household practices heavily rely on access to resources, such as adequate water and soap supply for regular handwashing, quality face masks and household disinfectants. Various theories of the 'Knowledge, Attitudes, Practices' model have assumed that individual knowledge enhancement will lead to positive behavioural changes. 130 Health measures targeting mask wearing might aim to enhance (i) the individual's risk perception, knowledge and awareness on protection effectiveness of masks, and how to properly wear a mask so that the prevention is most effective; (ii) an individual or community's attitude towards the practice of mask wearing and encouraging compliance in the west, as studies demonstrate a relatively greater social stigmatization towards mask wearing among Westerners than East Asians 131 and (iii) normalizing the practice of habitual mask wearing. Such a conceptual framework should be utilized in the implementation of the health initiatives. In terms of overarching knowledge, health education on symptom identification is also important, as seen on government platforms such as the CDC. 42 Enhancing health-seeking behaviour of potential carriers is critical to promoting a rapid response for quarantine or hospitalization.

At the individual level, behavioural changes have different sustainability potentials and limitations. Measures can also result in unintended consequences. For example, regarding the improper disposal of face masks 132 and the incorrect use of household disinfectants, 133 careful monitoring is critical in order to maximize impact while minimizing further health and safety risks. Topdown policy facilitation and strengthening of infrastructure will be essential for effective implementation. Top-down efforts in resource provision, such as the distribution of quality masks to all citizens by the government or similar authority, 134 enhance personal and household capacities to mitigate infection risks. Regarding compliance, the effectiveness of community practices, such as crowd and travel avoidance, is highly dependent on the needs and circumstances of an individual and a community. More assertive top-down policies such as travel bans and social distancing rules may drive bottom-up initiatives within communities under legal deterrence. 135 However, in order to ensure population-level compliance to recommendations that have wide-ranging socioeconomic impact and involve more than a day-to-day behavioural change, careful risk and information communication is required, which takes into consideration practical, legal and ethical aspects. Research into promoting behavioural change during the COVID-19 pandemic have suggested that public health professionals, policy makers and community leaders can enhance compliance by creating a sense of motivation in individuals rather than creating anxiety that can lead to defensive avoidance. 16 Information should be tailored and account for language, education and health literacy, with input from stakeholders, such as community leaders, religious heads or allied health workers, who can advise on how to enhance understanding of risks and benefits, especially if targeted at marginalized populations. 16 ,17 It is important to create a bipartisan, shared sense of identity and cooperative responsibility within the population, for example using collective terms such as 'us' or 'we' in risk communication, and using interdisciplinary approaches that bring together groups from different backgrounds, such as medical practitioners, epidemiology experts, community leaders and non-governmental agencies working at the grassroots level. 17 With regard to the strength of evidence available in the reviewed literature (Table 4) , the largest proportion of studies fell into Level 5 (69%) classification, which encompasses a range of study designs and methodologies such as narrative reviews, experimental studies, modelling studies and expert opinions. Less than 1% of the identified resources were classified into 'Others', which includes the WHO Dashboard for latest figures on COVID-19. Level 4 studies, such as cross-sectional studies and case series, contributed a relatively large portion (16%) with many focusing on the disease progression and patterns of specifically identified patients. The low proportion of Level 1 studies (7%) compared to Level 4 or 5 may be attributed to the novelty of Higher level studies generally involve more rigorous and stringent methodologies, which would inevitably require more time.

Regarding individual primary prevention measures, evidence is most lacking at all levels for the practices involving avoidance of utensil sharing (5%), bringing personal utensils (6%), travel avoidance (5%) and the closing of toilet lids when flushing (5%). On the other hand, most of the available evidence supports measures such as handwashing (20%), wearing face masks (19%) and avoiding crowds (14%). Literature relevant to regular handwashing was the strongest in terms of study design, with 26% of the total literature identified for this particular practice being Level 1 studies and 82% of all Level 1 studies identified being associated with regular handwashing. In the case of a novel or emerging disease such as COVID-19, there is limited available evidence that can be related specifically to the disease and pandemic, but some findings are deduced from studies on other similar viral infections and transmittable conditions, such as SARS or Influenza. Many measures proposed by health authorities are not based on rigorous population-based longitudinal studies. While handwashing is well regarded as a core measure by global and national public health agencies such as the WHO 41 and CDC, 42 and the chemical properties of eliminating enveloped viruses is well understood, 43 ,65 specific studies on the efficacy of practice and impact on COVID-19 transmission are lacking. Due to the uncertainties of disease pathology and epidemiology, effectiveness of behavioural measures against COVID-19 is far from conclusive. Other uncertainties are also reported on virus surface stability 20 and whether the efficacy of disinfectants against surface-stable viruses may vary with COVID-19. 79 Similar deductive evidence approaches from studies on other viruses have been utilized to judge the efficacy of face masks or the closing of toilet lids. 87,88 Although published evidence suggested individual measures such as covering coughs and sneezes to be helpful against droplet transmissions, 19 further research is needed to understand the true efficacy of coverings such as masks, tissues or elbows as an adequate preventive measure against COVID-19.

Given the rapid knowledge advancement and research updates related to COVID-19, further study updates will be warranted to identify the most appropriate behavioural measures to support bottomup biological hazard responses. Cost-effectiveness of the measures, their impact sustainability, cobenefits and risk implications on other sectors should also be examined and evaluated. Standardized studies across different contexts should be enhanced, for example conducting tests on the efficacy of different disinfectants or soaps under a standardized protocol. Such studies would increase evidence on individual and comparative efficacy of the behavioural measures.

The limitations in this review include language, database inclusion, online accessibility of the article, grey literature and informal publication outlets, and missed keywords. Search terms were determined using variations of terms for COVID-19 or respiratory viruses, as well as a number of preventive practices that are well documented. However, search terms did not encompass the full spectrum of terms relating to behavioural measures. For community practices, the terms searched included 'mass gathering' and 'social isolation' but not 'travel restriction', although limiting travel was later identified as a standalone measure through reviewing the literature search results. Publications documenting the experiences of traditional, non-English-speaking, rural communities during the COVID-19 pandemic may not have been identified in this review. Further research should review the efficacy of various measures in different contexts and make comparisons with their alternative measures. Specifically, alternative preventive measures that can be practiced in resource-poor, developing communities, whose health systems and economies generally suffer the greatest impact during pandemics, are urgently needed. Increased understanding of how to effectively mitigate against biological hazards such as COVID-19 in various contexts will help communities prepare for future outbreaks and build disaster resilience in line with the recommendations from the health-EDRM framework.

Despite the constraints, this review has nevertheless identified common, relevant behavioural measures supported by best available evidence for the design and implementation of health policies that prevent droplet-borne biological hazards. Many of the measures recommended by authorities during the pandemic are based on best practice available rather than best available evidence. The possibility of conducting large cohort or randomized controlled studies is often complicated, and rather infeasible during a pandemic, as noted for face masks. 136 ,137 Further studies are needed to understand the efficacy of frequently proposed measures for transmission risk reduction. Nonetheless, each of the measures identified has scientific basis in mitigating the risk of droplet transmission, 19 either through personal measures such as handwashing or community-based measures that aim to reduce person-to-person contact. The 10 measures identified in this review constitute only a portion of those non-pharmaceutical and primary preventive behaviours that can mitigate against the transmission of a droplet-borne disease and do not represent the entire spectrum of either non-pharmaceutical or primary prevention measures. Alternatively, the measures identified here can also fall into other subsets such as 'biological hazard prevention' or 'community outbreak prevention'. It is important to explore the efficacy of alternatives, notably for transmission prevention and risk communication in low-resource or developing contexts where the capacity of the health system to mitigate and manage outbreaks is weak. For example, while face masks are understudied, the scientific study of cloth masks as an alternative is severely limited, 70 although recommended by the CDC. 138 Such alternative studies should expand to consider different cultures and contexts where different varieties of disinfectants, face masks and utensils may be used. There is also potential for comparative effectiveness studies to explore measures that provide the greatest transmission risk reduction at the lowest transaction cost to the individual and community and should thus be prioritized in low-resource contexts. 139

During the outbreak of a novel transmittable disease such as COVID-19, primary prevention is the strongest and most effective line of defence to reduce health risks when there is an absence of an effective treatment or vaccine. COVID-19 is and will be subjected to ongoing research and scrutiny by global scientists, health professionals and policy makers. While research gaps remain on the efficacy of various health-EDRM prevention measures in risk reduction and transmission control of COVID-19, suboptimal scientific evidence does not negate the potential benefits arising from good hygiene practices, especially where the likelihood for negative outcome is minimal. Despite the lack of rigorous scientific evidence, the best available practice-based health education content, effective means of information dissemination, equitable access to resources and monitoring of unintended consequences of the promoted measures, such as environmental pollution due to poor waste management, will be essential. A top-down approach should be multi-sectorial, bringing in policy makers with clinical, public health, environmental and community management expertise to develop a coordinated and comprehensive approach in this globalized world. Individual RCT (with narrow confidence interval) 1c

All or none 2a SR (with homogeneity) of cohort studies 2b

Individual cohort study (including low quality RCT; e.g. <80% follow-up) 2c 'Outcomes' research; ecological studies 3a SR (with homogeneity) of case-control studies 3b

Individual case-control study 4

Case series (and poor quality cohort and case-control studies) 5

Expert opinion without explicit critical appraisal, or based on physiology, bench research or 'first principles' Others For example, model simulations, non-human-based experiment, in vitro or in situ studies, and statistical reports or dashboards

Health policy and technology challenges in responding to the COVID-19 pandemic

Emergency risk management for health -overview

Health emergency and disaster risk management: overview. Health Emergency and Disaster Risk Management Fact Sheets

Modes of transmission of virus causing COVID-19: implications for IPC precaution recommendations

Public Health and Disasters: Health Emergency and Disaster Risk Management in Asia

Encyclopedia of Epidemiology

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The authors wish to thank Dr Ryoma Kayano, from the WHO Centre for Health Development, for his valuable input and support into this publication.

The authors declare no conflicts of interest.

The study is fully funded by the CCOUC-University of Oxford research fund (2019-2023).

• Environmental burden of disease and association to air pollution is a main concern in the fast-developing areas of India