Abstract
Background:
There is an ongoing debate regarding the type of respiratory protection that should be recommended for use for healthcare workers.
Materials and methods:
A cross-sectional survey was conducted in three countries: China, Pakistan and Vietnam.
Results:
In China and Pakistan, the infection control guidelines were developed to be in line with the recommendations from the World Health Organization (WHO) and the Centers for Disease Control and Prevention, while in the Vietnamese guidelines the recommendations correspond with the WHO suggestions only. The guidelines from all three countries document the need for training and fit testing; however there is no system to monitor the training and fit testing programs. Across the three countries, there was some inconsistency with regard to the types of products (i.e. masks vs. respirators) recommended for influenza, severe acute respiratory syndrome (SARS) and tuberculosis.
Conclusions:
Available evidence should be examined and a comprehensive policy should be developed on the use of masks and respirators. The policy should address critical areas such as regulation, training, fit testing and reuse.
Keywords: Healthcare-associated infections, infection control, infectious diseases, public health
Introduction
Masks and respirators are commonly used in healthcare settings to protect hospital healthcare workers (HCW) from respiratory infections (Siegel et al., 2007; World Health Organization (WHO), 2014a). Masks are used to prevent HCWs acquiring infections from splashes of blood and body fluid and to reduce the transfer of potentially infectious body fluids in the sterile area. They are also used by coughing patients to try and prevent the spread of infections (Siegel et al., 2007; Institute of Medicine (IOM) National Academy of Sciences, 2010). However, masks were not designed to provide respiratory protection, as they have consistently lower filtration efficiency than respirators (Balazy et al., 2006; Lawrence et al., 2006). In comparison, a respirator is a fitted device that protects the wearer against the inhalation of small and large airborne particles, that is, it protects the wearer from others who are or might be infected (Occupational Safety and Health Administration (OSHA). U.S. Department of Labor, 2009). Respirators are generally considered to be superior to surgical or cloth masks (MacIntyre et al., 2011, 2013; van der Sande et al., 2008), but there is some evidence that both surgical masks and respirators are effective against respiratory infections (Seto et al., 2003; Loeb et al., 2009). The efficacy of both is still being debated in the literature. Although, previous observational and experimental studies have reported that masks and respirators may protect HCWs from respiratory infections (Gamage et al., 2005; Gralton and McLaws, 2010; MacIntyre et al., 2011, 2013,), there is very little high quality clinical evidence to determine their efficacy (Cowling et al., 2010; Bin-Reza et al., 2012).
A recent review of the policies and guidelines from the World Health Organization, the Centers for Disease Control and Prevention (CDC), and from three high-income countries and six low/middle-income countries highlighted that each organisation/country has different approaches and recommendations regarding the use of masks/respirators in the hospital setting (Chughtai et al., 2013a). The type of product recommended and terminology used to describe the product, were the main inconsistencies observed. In addition, most of the guidelines did not provide any detail about the length of use, reuse and extended use of masks and respirators (Chughtai et al., 2013a).
To further explore the issues which arose during the guideline review, a cross-sectional survey was conducted in China, Pakistan and Vietnam. The aims of this study were to explore the recommendations around mask type recommended in these countries and to clarify if there are any recommendations regarding the use and reuse of various types of masks and respirators.
Methods
A cross-sectional survey was undertaken in three countries: China, Pakistan and Vietnam. Data collection was undertaken between March and September 2013.
Participants
A range of stakeholders from the three countries was identified to participate in the study, including those from the: (1) Ministry and the Department of Health; (2) in-country Centers for Disease Control and Prevention; (3) vertical disease control programs; and (4) relevant public and private health organisations involved in the development of infection control policies and guidelines.
We liaised with local researchers from each country, to assist with obtaining local ethics approval, to identify and recruit key stakeholders and to undertake the survey via a face-to-face interview. The local researchers were located in various health departments including the Beijing Center for Disease Control and Prevention (CDC) in China, the National TB Control Program (NTP) in Pakistan and the National Institute of Hygiene and Epidemiology (NIHE) in Vietnam.
An invitation letter was sent to the identified stakeholders in each of the countries via email or mail. The stakeholders were called one week later to confirm whether they had received the letter and whether they were interested in participating in the study. If they agreed, the local researchers conducted a face-to-face interview. If the identified stakeholder was not the relevant person or did not have all information required to answer the questions, he or she was asked to provide the contact details of another suitable person in the organisation. Participants were only included in the study when full written consent had been received. Five stakeholders from each country were identified and interviewed.
Survey
A structured questionnaire was developed based on our previously published studies (MacIntyre et al., 2011, 2013) and on the currently available guidelines regarding the use of masks and respirators from each of the countries (Chughtai et al., 2013a). The questionnaire explored the following aspects: (1) development of the guideline/policy (year of development, authorship etc.); (2) policy and/or recommendations made for the use of masks and respirators for influenza, severe acute respiratory syndrome (SARS) and tuberculosis (TB) (what types of masks and respirators are commonly recommended?; What is the policy around the use of cloth masks?; What are the policies around the regulation, training and fit testing?) and (3) policies in place for reuse of masks and respirators (Is reuse recommended or not?; What are common decontamination techniques?). Both closed and open ended questions were included in the survey. The questionnaire was pilot tested in one country, and then further refined. The questionnaire was translated into Chinese and Vietnamese languages.
Three diseases were selected for this study: influenza, SARS and TB, based on previous analysis of policies and guidelines (Chughtai et al., 2013a). The risk of these diseases is assumed to be higher among HCWs in comparison to members of the general public, and awareness about policies around these diseases was assumed to be higher (WHO, 2014b; Dimitrova et al., 2005; Kuster et al., 2011). Influenza was selected as the primary infection of interest. It includes seasonal influenza, avian influenza and pandemic influenza. Newly emerging infections have increased in recent years, resulting in morbidity, mortality and an increase in associated costs. SARS was selected as an example of an emerging infectious disease. TB was selected as an example of a chronic but highly infectious disease. In contrast to influenza and SARS, TB has a long incubation and infectious period.
Mask and respirator reuse is referred to in this study as extended use and reuse after decontamination. Extended use was defined as using a mask or respirator by the same wearer for a long time, i.e. for more than one shift or one day. Reuse after decontamination was defined as decontaminating masks or respirators and reuse by the same or a different wearer.
Data collection and analysis
Local research groups completed the survey via a structured interview. The survey was completed in the local languages in China and Vietnam and in English in Pakistan. All interviews were audio recorded and transcribed. The research groups in China and Vietnam transcribed the surveys into English before the analysis stage. Survey data were entered into an Excel Spreadsheet 2010 (Microsoft Corporation). Separate tables were made for each country and question type. Open ended questions were examined and coded for themes and subthemes and thematic analysis was performed. Two researchers (AAC and HS) reviewed all data and prepared a list of themes and subthemes separately. Both lists were then collectively reviewed and a final list of themes and subthemes was prepared, and applied to whole dataset. Data were double checked for errors. In case of gross errors or inconsistencies, the original recordings were referred to.
Ethics approval
Primary ethics approval was obtained from the Human Research Ethics Advisory (HREA) Panel of the University of New South Wales, Sydney, Australia (Approval no 2012-7-40). Approval was also sought from the Beijing Center for Disease Control and Prevention (CDC) China, Pakistan Medical and Research Council (PMRC), Islamabad Pakistan and the Institutional Review Board at the National Institute for Hygiene and Epidemiology (NIHE), Hanoi Vietnam.
Results
In all of the surveyed countries, recommendations regarding the use of masks/respirators are captured in both general infection control policies, as well as disease-specific guidelines for seasonal influenza, pandemic influenza, avian influenza, SARS and TB. The majority of the documents are targeted at healthcare providers; however some also include recommendations for patients and community members. Although the guidelines from both Pakistan and China discuss in detail the use of masks/respirators, only the Chinese policy includes information regarding the regulation and certification processes for respirators. In Vietnam, the use of masks/respirators is only briefly discussed in the national policy. While the guidelines from all three countries document the need for training and fit testing, there is no specific guidance provided about the implementation and monitoring of training/fit testing programs.
Guidelines on the use of personal protective equipment, when dealing with respiratory viruses of unknown origin, partially existed in China and Vietnam prior to the 2002–03 SARS outbreak. According to the participants interviewed, most of these guidelines were developed during the SARS outbreak. The quality and effective use of masks were emphasised in the new guidelines. During the 2009 H1N1/A influenza pandemic, participants from all three countries reported that further revisions were made to the guidelines based on information obtained from the WHO and CDC. In the initial phase of the pandemic, N95 respirators were recommended for everyone; however, this recommendation was subsequently revised later on so that N95 were only recommended during high-risk procedures.
In light of the recent emergence of novel coronavirus (MERS) and influenza H7N9, new infection control guidelines are currently being developed in China. Pakistan is also developing a guideline on TB infection control in healthcare facilities and is updating policy on the hand hygiene.
With regard to the use of personal protective equipment for HCWs, the recommendations from Pakistan and China were developed to be in line with the recommendations made by WHO and the CDC. During the initial development stages, the European Centre for Disease Control (ECDC) guidelines were also considered. In comparison, the guidelines are in line with the WHO recommendations in Vietnam only.
When asked to clarify whether specific recommendations for mask use were made according to a risk classification, participants from all three countries confirmed that they were. The description of low- and high-risk situations, however, varies in the guidelines (Table 1). Across the three countries, there is some inconsistency about the types of products recommended for seasonal influenza, pandemic influenza, avian influenza, SARS and TB. For seasonal and pandemic influenza, paper, cloth and surgical masks are all recommended for low-risk activities, whereas only surgical masks and respirators are recommended for high-risk activities. For dealing with either a SARS or avian influenza patient, the guidelines vary between country and between high/low-risk situations. Various mask types are recommended for use in low-risk clinical situations with a TB patient, whereas surgical masks and respirators are recommended in high-risk situations. Paper and cloth masks are less commonly recommended in China and Pakistan than in Vietnam.
Table 1.
Description of low- and high-risk situations in various infection control policies and guidelines in China, Pakistan and Vietnam.
Country | Description of low risk | Description of high risk |
---|---|---|
China |
|
|
Pakistan |
|
|
Vietnam |
|
|
‘Extended use’ of masks is not recommended in the Chinese and Vietnamese guidelines; however, during the interviews in Pakistan it was suggested that the practice is commonplace. In comparison, the ‘reuse’ of mask and respirators is not recommended in any guidelines. According to the Vietnamese guidelines, reuse of wet masks is not recommended, nor is it recommended to place a mask into the pocket or wear it loose around the front of the neck for the purpose of reuse. However, when reflecting about the reuse of masks, participants highlighted that the recommendation of only using a mask once was infeasible because of cost and that in reality staff often resort to reusing their masks or extending the time they are worn for.
Participants discussed various challenges regarding the implementation of national policies and guidelines. Despite the development of guidance documents, participants felt that the guidelines are rarely followed, which may be due to a number of reasons including a lack of regulatory mechanism, scarce resources and unavailability of trained staff. It was also suggested that the implementation of guidelines also varies among public and private hospitals. Most hospitals do not have established infection control committees, nor do they have arranged training programmes for staff. Some participants proposed to establish national groups for monitoring of guidelines implementation. Other participants suggested that health department should lead the process and provide updated information on the use of masks and respirators in the healthcare setting.
Discussion
In this study we explored the recommendations around the use of masks and respirators from three Asian countries. In all of the settings, national infection control policies and disease-specific policies for pandemic influenza, seasonal influenza, avian influenza, SARS and TB are in existence; however the recommendations regarding the types of masks that should be used differ. Most of the guidelines were developed in the aftermath of either the SARS outbreak in 2002–03 and the emergence of avian influenza in 2004–2005.
The results from this study highlight the variations across the three countries in regards to the recommendations and guidelines around the use of masks/respirators. In low-risk situations, various products are being recommended by all three countries, ranging from paper masks, cloth masks, surgical masks and respirators. However in high-risk situations, surgical masks and respirators are commonly recommended in all three countries.
Currently it is not apparent what factors are being taken into account when these recommendations are being made. In an ideal setting, the selection of an appropriate type of respiratory protection should depend on the mode of disease transmission. Droplet and contact is considered the primary mode of transmission for influenza (Brankston et al., 2007; CDC, 2014a) and SARS (CDC, 2004), and therefore surgical masks may be sufficient to protect HCWs during routine care. However studies have shown that the risk from infections increases during ‘high-risk situations’, for example, when undertaking tracheal intubation, bronchoscopy, non-invasive ventilation and other aerosol generating procedures (Tran et al., 2012; Thompson et al., 2013; Macintyre et al., 2014). The risk is primarily due to increased production of respiratory aerosols during these procedures, which might contain more viruses (Milton et al., 2013). In addition some diseases, like TB, exclusively transmit through respiratory aerosols (Riley et al., 1995, Siegel et al., 2007). Respirators should be preferred when there is a risk of aerosol transmission as they are designed for respiratory protection and are more effective than surgical and cloth masks (van der Sande et al., 2008; MacIntyre et al., 2011, 2013).
As highlighted by our participants, the development of national guidelines was in accordance with either the recommendations from the WHO or from the US CDC or both. As previously documented by our team, the WHO and CDC themselves differ in their recommendations regarding the use of masks/respirators for some diseases (Chughtai et al., 2013a). This probably explains some of the differences identified in this present study. However it does not explain all of the choices being made. For example, paper and cloth masks are not recommended by the WHO and the CDC but were listed in the policies from all three countries. Although the efficacy of cloth masks is not proven yet and their role in prevention of infections is uncertain (Institute of Medicine (IOM) National Academy of Sciences, 2006), cloth masks may be the only option available to HCWs in some situations due to resource and financial limitations. For example, cloth masks were commonly used in China (Yang et al., 2011) and Vietnam (Le et al., 2004) during the SARS outbreak in 2002–03. There is a clear gap in the cloth masks research and very few studies have been conducted to test the efficacy of cloth masks since the development of surgical masks in the middle of the 20th century (Chughtai et al., 2013b). There is a need to conduct further research on cloth masks, given that some countries will continue to depend on them, which focuses on improving the design and material.
In our study, only China has regulations over the use of respirators. Although respirators are being used in Pakistan and Vietnam, there is no regulatory body to monitor their use. In some hospitals in Vietnam, the Department of Hospital Infection Control monitors the use of masks, hand hygiene and sterilisation; however there is no central regulatory body. Regulations over the use of respirators exist in most high income countries. For example, the National Institute for Occupational Safety and Health (NIOSH) regulates the testing and certification of respiratory protection equipment in the US. The NIOSH tests filters for the effects of loading, particle burden, temperature, and relative humidity and requires a minimum filtration efficiency of 95%, 99% or 100% (Institute of Medicine (IOM) National Academy of Sciences, 2010). In Europe, the European Norm (EN) standards are followed for testing respirators. The respirators are required to be marked with ‘Conformité Européen’ (CE), which means that the respirator meets the criteria of the EN certification. In Australia, the AS/ NZS 1716 standard regulates the respirator use (Standards Australia Limited/Standards New Zealand, 2012). In low/middle income countries, barriers such as lack of resources, government motivation and technical expertise may impact on the introduction of similar regulations.
In our study, extended use was recommended only in Pakistan, while the reuse of masks was not recommended in any country. Currently there is a lack of data regarding the period in which the same mask or respirators may be used continuously. Generally, disposable masks and respirators have a limited lifespan and may become deformed, damaged or may become infective after the single use (IOM National Academy of Sciences, 2006). Reuse after decontamination is defined as decontaminated masks or respirators and reuse by the same or a different wearer. Decontamination of masks and filtering piece respirators is usually not feasible because the materials of these masks are likely to degrade with standard means of disinfection, for example boiling, chemicals, heat and radiation (IOM National Academy of Sciences, 2006). Currently there is no standard method to disinfect disposable masks and respirators. Ultraviolet germicidal irradiation (UVGI), microwave-generated steam (MGS), moist heat (MH), ethylene oxide and vaporised hydrogen peroxide are a few options which have been previously suggested to decontaminate respirators (Viscusi et al., 2009; Lore et al., 2012).
The reuse of masks and respirators is generally not recommended due to the risk of self-contamination and adverse events (IOM National Academy of Sciences, 2006), however, this may be the only option in some resource limited settings or during the outbreaks and pandemics. During the SARS outbreaks, Health Canada advised hospital staff to use their masks and respirators for an extended period if their patient was SARS negative (Health Canada, 2003). WHO advises HCWs to use respirators for extended period for TB protection, if they are properly stored (WHO, 1999).The CDC recommends that extended use and reuse should be balanced against the risk of infections and extended use is preferred over reuse if required (CDC, 2014b). Further studies should be conducted to examine the effectiveness of masks being used for an extended period and to test the effectiveness of various decontamination methods. The number of virus particles isolated, the length of virus survival, effect on mask material and HCWs’ compliance are important factors to consider while recommending mask reuse (IOM National Academy of Sciences, 2006; CDC, 2014b).
Our study has some limitations. While we attempted to identify the most relevant participants from various health departments and organisations, we may have failed to include all relevant stakeholders. However, given that we worked with local health organisations to recruit participants, we feel that this limitation was minimised. In addition, there was a chance of recall bias due to the time of guideline development. A few of the guidelines were developed before 2003 and participants may not be able to recall some of the recommendations. These guidance documents may contain up to date recommendations, which are not included in this study.
Conclusion
Countries have various policies and guidelines around the use of masks and respirators. Paper, cloth and surgical masks are generally recommended for low-risk situations, whereas for high-risk situations, surgical masks and N95 respirators are suggested. The guidelines are not up to date and reuse is not discussed in most of the guidelines. There is a need to examine available evidence and develop a comprehensive policy on the use of masks and respirators in various respiratory infections. The policy should address critical areas, like regulation, training and fit testing. A mechanism should be developed to monitor the process of guideline implementation.
Footnotes
Declaration of conflicting interests: Professor C. Raina MacIntyre: Raina MacIntyre has held an Australian Research Council Linkage Grant with 3M as the industry partner, for investigator driven research. 3M have also contributed supplies of masks and respirators for investigator-driven clinical trials. She has received research grants and laboratory testing as in-kind support from Pfizer, GSK and Bio-CSL for investigator-driven research. Dr Holly Seale had a NHMRC Australian based Public Health Training Fellowship at the time of the study (1012631). She has also received funding from vaccine manufacturers GSK, bio-CSL and Saniofi Pasteur for investigator-driven research and presentations. The remaining authors declare that they have no competing interests and have no non-financial interests that may be relevant to the submitted work.
Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Peer review statement: Not commissioned, blind peer-reviewed.
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