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1 Introduction During an influenza pandemic, healthcare workers will be on the front lines delivering care to patients and preventing further spread of the disease. Protecting these workers from illness or from infecting their families or the patients in their care is critical to managing pandemic in- fluenza and limiting morbidity and mortality. Pandemic influenza will place enormous demands on the healthcare system that include protect- ing healthcare workers at the center of these efforts. As the nation prepares for pandemic influenza, multiple avenues for protecting the health of the public are being carefully considered, ranging from rapid deployment of appropriate vaccines to quarantine plans should the need arise for their implementation. One vital aspect of pan- demic influenza planning is the use of personal protective equipment (PPE)1âthe respirators, gowns, gloves, face shields, eye protection, and other equipment that will be used by healthcare workers and others in their day-to-day patient care responsibilities. However, efforts to appro- priately protect healthcare workers and their families and patients are greatly hindered by the paucity of data on the transmission of influenza and the challenges associated with training and equipping healthcare workers with effective PPE. Due to this lack of information on influenza transmission, it is not possible at the present time to definitively inform 1 This report defines the term personal protective equipment (PPE) as the equipment that is designed and worn to protect the wearer from exposure to hazardous agents. The term encompasses respirators, gowns, gloves, faceshields, and eye protective equipment as well as some head and shoe coverings. As discussed later in the chapter, the committee does not include medical masks (surgical or procedure masks) as PPE because they are not designed to be used to protect the wearer from hazardous exposures. 19
20 PREPARING FOR AN INFLUENZA PANDEMIC healthcare workers about what PPE is critical and what level of protec- tion this equipment will provide in a pandemic. Prior to the 1980s, the use of healthcare PPE was largely confined to surgical settings and was primarily intended to protect patients rather than healthcare workers. Although infectious exposures to healthcare workers had long been recognized, with the emergence of HIV/AIDS and the resurgence of tuberculosis in the 1980s, emphasis was refocused on PPE for the protection of healthcare workers in all settings. Standard infection control precautions, advanced by the Centers for Disease Con- trol and Prevention (CDC) in the late 1980s, first defined the spectrum of barrier precautions for the protection of healthcare workers (CDC, 1988). The Occupational Safety and Health Administration (OSHA) bloodborne pathogens standard, finalized in 1991, made these protections mandatory (OSHA, 1991). Most recently, the outbreaks of severe acute respiratory syndrome (SARS) in 2003 have underscored the importance of protect- ing healthcare workers from infectious agents. The surge capacity that will be required to reduce mortality from a pandemic cannot be met if healthcare workers are themselves ill or are absent due to concerns about PPE efficacy. The increased emphasis on healthcare PPE and the related challenges that are anticipated during an influenza pandemic necessitate prompt attention to ensuring the safety and efficacy of PPE products and their use. In 2000, the Institute of Medicine (IOM) report To Err Is Human: Building a Safer Health System provided a call to action for building safer healthcare systems and raising the bar for patient safety. In recent years, many healthcare systems have begun extensive efforts to improve the patient safety infrastructure by combating medication and other medical errors as well as incorporating information technology into their management structures. The increased emphasis on patient safety is a strong foundation that should be coupled with an equally strong empha- sis on the safety of healthcare workers, including the use of PPE. Ensur- ing the safety of the healthcare workforce will have additive benefits in reducing the risk of disease transmission to patients and preserving the quality of patient care. In 2005, the National Personal Protective Technology Laboratory (NPPTL) at the National Institute for Occupational Safety and Health (NIOSH) asked the IOM to form a standing committee to provide strate- gic guidance in addressing PPE issues for a wide range of workers. One issue that the IOM standing committee and NPPTL deemed of high im- portance is the topic of this reportâenhancing the PPE for healthcare
INTRODUCTION 21 workers in the event of pandemic influenza. This report is the result of a 12-month study begun in 2006 and conducted by an ad hoc IOM com- mittee composed of experts in the fields of infectious disease, infection control, public health, occupational safety and health, emergency medi- cine, emergency response and preparedness, community health, indus- trial hygiene, internal medicine, and materials engineering. SCOPE OF THIS REPORT The IOM committee was charged with examining research direc- tions, certification and the establishment of standards, and risk assess- ment issues specific to PPE for healthcare workers during an influenza pandemic. The committee was specifically asked to focus on â¢ research needed to understand and improve the efficacy and effectiveness of PPE, particularly respirators, for an influenza pandemic, with attention to improving functionality and addressing human factors such as wearability, compliance, and communications; â¢ necessary certification, testing, and standards development requirements, with attention to clarifying the roles of NIOSH, NPPTL, the Food and Drug Administration (FDA), OSHA, and nongovernmental standards-setting organizations; and â¢ priorities and resources for research and certification efforts. To accomplish its charge, the committee held three meetings and gathered information through a scientific workshop (Appendix A) that included a public comment session, through discussions with numerous individuals in the infection control and occupational safety and health fields, and by conducting a review of the relevant literature. This report also benefits from the work of prior IOM committees and workshops that have examined issues related to PPE and to pandemic influenza (IOM, 2005a,b, 2006, 2007). Many of the issues related to PPE for healthcare workers are directly relevant to the PPE needs of workers in other occu- pations, as well as the general public. The committee believes that the recommendations in this report will have a broad impact on improving the quality, relevance, and use of PPE while enhancing the culture of safety in diverse occupations.
22 PREPARING FOR AN INFLUENZA PANDEMIC PPE IN PERSPECTIVE: PANDEMIC INFLUENZA PLANNING In the United States and across the globe, plans are being developed and investments are being made for a rapid response to an influenza pan- demic (DHHS, 2005, 2006a,b, 2007; WHO, 2005; OSHA, 2007b). In part, this has been spurred by increases in avian-to-human transmission of influenza and by concernsâin light of past pandemics, particularly those of 1918, 1957, and 1968âabout current underpreparation for the next influenza pandemic. Strategies being implemented include im- provements in surveillance and monitoring efforts, enhancements in vac- cine production capacity, an analysis of the safety and efficacy of antiviral medications, stockpiling of antiviral medications and other sup- plies (including PPE), and enhancing medical surge capacity and state and local preparedness, including extensive community planning efforts (Barnett et al., 2005; DHHS, 2006a,b, 2007). Resources necessary for pandemic influenza planning are drawn from local, state, federal, non- profit, and for-profit organizations and agencies. Extensive training exer- cises and educational and communications programs have been initiated. Investment in PPE, particularly respirators, is one area of focus in national planning for an influenza pandemic. The U.S. national planning for medical preparedness stockpiles called for purchases totaling $162 million in 2006 for medical supplies including 50 million medical masks and 50 million N95 respirators (DHHS, 2006a). States and local areas are also purchasing PPE in anticipation of a pandemic. However, because of the prolonged nature of a pandemic, research and development innova- tions are needed to address issues of equipment reusability and disinfec- tion (IOM, 2006). Further, the challenges involved in the manufacturing surge and the logistics for delivery of PPE to healthcare facilities2 need to be addressed. Ethical Considerations In an influenza pandemic, ethical quandaries are likely to be faced, especially as needed supplies become scarce. In addition, priorities will have to be determined regarding the use and distribution of vaccines and 2 The term healthcare facilities is used in this report to encompass all sites of healthcare delivery including hospitals, long-term care facilities, pre-hospital facilities, home care, and private medical and dental offices.
INTRODUCTION 23 antiviral medications or the implementation of quarantines. The more that can be done to address issues of priorities for supplies (including PPE) and to anticipate the ethical challenges and the needs of healthcare employers and workers, the better prepared the nation will be for an in- fluenza pandemic. One ethical issue being discussed in this pre-pandemic planning pe- riod is the assessment of risks for healthcare workers.3 The expertise of healthcare workers is an integral and principal component of the response to a pandemic. Heightened work demands and increased chance of exposure to infectious agents will necessitate that healthcare workers and employers evaluate responsibilities with regard to the personal safety of the worker, his or her duty to work, and the safety and care of the employeeâs family members. Discussions of these responsibilities point to the need for an ethical framework for pandemic planning that considers the balance of reciprocity, beneficence, and autonomy in decision making. For employers, and society more broadly, reciprocity includes the re- sponsibility to actively support healthcare workers by providing up-to- date training, equipment, communication measures, and other tools needed to effectively educate, protect, and communicate with workers as they perform their duties to ensure the lowest possible level of risk (Kotalik, 2005). Healthcare organizations should dedicate sufficient re- sources to ensure that these measures are easily accessible, maintained, and supported by healthcare management. Equal access and culturally competent training are needed for all workers at healthcare facilities who will be expected to come to work and keep the facility running smoothly during a pandemic. Plans should be developed, implemented, and evalu- ated with substantial input from workers at all levels so that not only direct patient care, but also all aspects of healthcare support efforts that may result in potential opportunities for exposure to infection, are considered. For healthcare workers the principle of beneficence involves provid- ing care to patients and the obligation on the part of healthcare workers to further the welfare of patients and to advance patientsâ well-being. The principle of beneficence is generally accepted as a basic foundation of the patient-provider relationship (Ruderman et al., 2006). 3 The term healthcare workers is broadly defined (as discussed later in the chapter) to include all workers in healthcare offices and facilities including individuals responsible for patient care, food services, facilities maintenance, and administration and those indi- viduals working in home health care and emergency medical services.
24 PREPARING FOR AN INFLUENZA PANDEMIC The principle of autonomy in decision making is a substantial factor in risk assessment. This principle implies that when the healthcare or- ganization provides adequate safety and protective measures, the deci- sion to provide patient care should be considered as minimal or low risk for infectious agent transmission and resulting illness. On the other hand, if adequate protective measures are not secured, providing patient care may be considered high risk and should be questioned. In this instance, it is the obligation of the healthcare organization to provide adequate pro- tective measures to safeguard the healthcare worker and workforce. Rec- ommendations have been made to strengthen the ethical codes of healthcare workers to provide guidance as to their responsibilities and rights during high-risk situations (Joint Centre for Bioethics, 2005). Occupational Safety and Health Context PPE is an important component in the continuum of safety efforts. Occupational safety and health measures have traditionally followed a hierarchy of controls. Engineering and environmental controls, such as air exchanges or negative-pressure rooms that can isolate the hazard or reduce exposure, are considered the first line of defense against hazard- ous exposures because they are ubiquitous measures that affect a large number of workers and patients and do not depend on individual compli- ance (Table 1-1; Thorne et al., 2004; Ulrich et al., 2004). Administrative controls include the policies, standards, and procedures set within an or- ganization to limit hazardous exposures and improve worker safety, in- cluding the provision of appropriate and effective protective equipment. At the individual level, responsibilities incumbent on the healthcare worker include appropriate use of PPE as well as adherence to work safety practices. The selection of specific PPE options for a given task must be de- termined within the context of the multiple layers of controls. The con- tribution to disease prevention provided by each of these layers of exposure control (including PPE) is likely to vary considerably based on task and local conditions. All relevant work situations with the potential for infection risk (such as cleaning patient rooms, delivery of food) must be considered in addition to direct patient care. The goal is to develop a
INTRODUCTION 25 TABLE 1-1 Examples of Occupational Safety and Health Controls Engineering and Personal Protective Environmental Administrative Equipment and Work Controls Controls Practices â¢ Ventilationâair â¢ Culture of safety â¢ Hand hygiene exchanges â¢ Availability of â¢ Wearing PPE â¢ Negative-pressure PPE â¢ Vaccination rooms â¢ Patient access â¢ Antivirals â¢ Isolation rooms restrictions â¢ Adhering to other â¢ Anterooms â¢ Source control safety precautions â¢ Filtration â¢ Policies regarding â¢ Encouraging peers â¢ Waste disposal PPE, vaccination, to follow safety â¢ Cleaning etc. precautions â¢ PPE design â¢ Education and training â¢ Enforcement, Supervision continuum of effective safety actions that can be implemented concur- rently by healthcare institutions, administrative units, and healthcare workers to protect against workplace hazards. Although there are research opportunities in each of these areas of controls, it is the purview of this report to focus on PPE and to provide recommendations for improving PPE and its utilization. HEALTHCARE WORKERS: DEFINING THE SCOPE More than 13 million workers in the United States (approximately 10 percent of the U.S. workforce) are employed in the healthcare field (Ta- ble 1-2; BLS, 2006). The committee broadly defines healthcare workers to encompass all workers employed by private and public healthcare of- fices and facilities as well as those working in home health care and emergency medical services. The definition would also include health professional students who are working at or receiving instruction in healthcare facilities. As indicated in Tables 1-2 and 1-3, the breadth of the term healthcare workers encompasses professional and support services; includes individuals involved in administration, patient care, and facilities care; and represents individuals working for private- and
26 PREPARING FOR AN INFLUENZA PANDEMIC public-sector employers as well as those who are self-employed. The healthcare workforce in the United States is culturally diverse and en- compasses a spectrum of educational levels. Further, the employment of many temporary and part-time workers also adds to the challenges and complexity of disseminating information within this job sector. Offices of physicians, dentists, or other healthcare professionals ac- counted for approximately 75 percent of the estimated total of 545,000 healthcare establishments in 2004. Those offices employed approxi- mately 25 percent of the 2004 healthcare workforce (BLS, 2006). Hospi- tals, constituting about 2 percent of the total number of healthcare facilities in 2004, were the largest healthcare employers, employing 41.3 percent of healthcare workers. Nursing and residential care facilities em- ployed 21.3 percent and home health care employed 5.8 percent of the healthcare workforce. TABLE 1-2 U.S. Healthcare Workers, Location of Employment Projected Change 2004 Employment (% increase) (thousands) 2004-2014 Hospitals, public and private 5,301 13.1 Nursing and residential care 2,815 27.8 Facilities Offices of physicians 2,054 37.0 Home healthcare services 773 69.5 Offices of dentists 760 31.7 Offices of other healthcare 524 42.7 practitioners Outpatient care centers 446 44.2 Other ambulatory healthcare 201 37.7 services Medical and diagnostic 189 27.1 laboratories Total 13,063 27.3 SOURCE: BLS, 2006.
INTRODUCTION 27 TABLE 1-3 Employment of U.S. Healthcare Workers by Occupation, 2004 Number Occupation (thousands) Percentage Total, all healthcare occupations 13,062 100.0 Management, business, and financial 574 4.4 occupations Professional and related occupations 5,657 43.3 Registered nurses 1,988 15.2 Licensed practical and licensed vocational 586 4.5 nurses Physicians and surgeons 417 3.2 Therapists 358 2.7 Diagnostic-related technologists and 269 2.1 technicians Clinical laboratory technologists and 257 2.0 technicians Health diagnosing and treating practitioner 226 1.7 support technicians Social workers 169 1.3 Dental hygienists 153 1.2 Counselors 152 1.2 Emergency medical technicians and 122 0.9 paramedics Dentists 95 0.7 Physician assistants 53 0.4 Service occupations 4,152 31.8 Nursing aides, orderlies, and attendants 1,230 9.4 Food preparation and serving-related 462 3.5 occupations Home health aides 458 3.5 Building cleaning workers 365 2.8 Medical assistants 361 2.8 Personal and home care aides 312 2.4 Dental assistants 257 2.0 Physical therapist assistants and aides 95 0.7 Medical transcriptionists 81 0.6 Office and administrative support occupations 2,379 18.2 NOTE: This table does not list all specific occupations within each category; therefore, totals do not achieve 100 percent. SOURCE: BLS, 2006.
28 PREPARING FOR AN INFLUENZA PANDEMIC The committee acknowledges that in the midst of an influenza pan- demic many people outside of the healthcare workforce will become caregivers, including many family members. It is hoped that improve- ments in PPE for healthcare workers will result in improvements in PPE for other caregiving adults as well. PERSONAL PROTECTIVE EQUIPMENT FOR HEALTHCARE WORKERS: AN OVERVIEW The unique characteristics of the healthcare industry regarding use of PPE are important to consider throughout this report. With the goal or âproductâ of the healthcare industry being human health and well-being, healthcare jobs and exposures involve working with or acting upon an- other living human being as distinct from an inanimate object or produc- tion process. Split-second actions in some healthcare situations can have major consequences and exposure monitoring is not a routine facet of protecting healthcare workers. Thus, although the usual barriers and en- cumbrances associated with PPE usage (such as communication interfer- ence and physical discomfort) are operative, they are compounded by the unique features of patient interaction. Further, there is a strong tradition among healthcare workers and healthcare institutions that the patientâs needs come first. Thus, opportunities are available to incorporate an em- phasis on worker safety and to integrate worker and patient safety efforts. For many healthcare workers, the use of some type of PPE, particu- larly medical gloves, occurs on a daily basis as part of infection control precautions that are designed to protect both the healthcare worker and the patient from disease acquisition. Varying types of PPE are recom- mended. The first of the two tiers of infection precautions developed by CDCâs Hospital Infection Control Practices Advisory Committee (Box 1-1; Garner and HICPAC, 1996; Siegel et al., 2007) consists of the stan- dard precautions4 and is designed to protect healthcare workers from 4 Standard precautions apply to the care of all patients and synthesize the major features of universal precautions (designed to reduce the risk of transmission of bloodborne pathogens) and body substance isolation recommendations (designed to reduce the risk of transmission of pathogens from moist body substances) (Garner and HICPAC, 1996). These guidelines apply to potential contact with blood; all body fluids, secretions, and excretions except sweat, regardless of whether or not they contain visible blood; nonin- tact skin; and mucous membranes.
INTRODUCTION 29 BOX 1-1 Overview of PPE Use in Infection Control Precautions Tier 1ââStandard Precautions Designed as the primary strategy for the prevention of healthcare- associated transmission of infectious agents among patients and health- care personnel. â¢ GlovesââWear when touching blood, body fluids, secretions, excre- tions, mucous membranes, nonintact skin, and contaminated items. Remove gloves promptly after use and follow hand hygiene guidelines. â¢ Mask,5 Eye Protection, Face ShieldââWear to protect mucous membranes of the eyes, nose, and mouth during procedures and patient-care activities that are likely to generate splashes or sprays of blood, body fluids, secretions, and excretions. â¢ GownââWear a gown appropriate to the task to protect skin and avoid soiling or contamination of clothing when contact with blood, body fluids, secretions, and excretions is anticipated. Remove gown and perform hand hygiene before leaving the patientâs environment. â¢ Other areas addressed include hand hygiene, cleaning of patient- care equipment and the environment, care and disposal of soiled linens, occupational health protections regarding bloodborne patho- gens, and patient placement. Tier 2ââTransmission-Based Precautions Used in addition to standard precautions. Transmission-based precau- tions may be combined for protection from diseases with multiple modes of transmission. Contact PrecautionsââIntended to prevent the transmission of infectious agents spread by direct or indirect contact with the patient or the patientâs environment. In addition to standard precautions, contact precautions require the following: â¢ GlovesââWear gloves whenever touching the patientâs intact skin or surfaces and articles in close proximity to the patient. Don gloves upon entry into the room. â¢ GownââWear a gown whenever anticipating that clothing will have direct contact with the patient or potentially contaminated environ- 5 In discussing the literature on respiratory protection, this report uses the terminology (masks or respirators) employed by the investigators or authors of the cited journal arti- cle or report. In some cases, it is not possible to determine whether the authorsâ use of the term masks refers to medical masks, respirators, or both.
30 PREPARING FOR AN INFLUENZA PANDEMIC mental surfaces or equipment in close proximity to the patient. Don gown upon entry into the room or cubicle. Remove gown and ob- serve hand hygiene before leaving the patient-care environment. â¢ Other areas addressed include patient placement, patient transport, patient-care equipment and devices, and environmental measures. Droplet Precautionsâ-Intended to prevent transmission of infectious agents spread through close respiratory or mucous membrane contact with respiratory secretions. In addition to standard precautions, droplet precautions require the following: â¢ Maskâ-Don a mask upon entry into the patient room or cubicle. â¢ Other areas addressed include patient placement and patient transport. Airborne Precautions-âIntended to prevent transmission of infectious agents that remain infectious over long distances when suspended in the air. In addition to standard precautions, airborne precautions require the following: â¢ Respiratory protection-âWear a fit-tested NIOSH-approved N95 or higher level respirator for respiratory protection when entering the room or home of a patient who is suspected or confirmed to have an airborne infectious disease. â¢ Other areas addressed include patient placement, patient transport, personnel restrictions, and exposure management. SOURCE: Siegel et al., 2007. acquiring diseases from a patient who may or may not be infected. Stan- dard precautions are applied to the care of all patients, regardless of their presumed infection status. The second tier of precautions is applied to patients with documented or presumed infections or conditions that could be transmitted to healthcare workers. The details of these transmission- based precautions are specific to situations with the potential for contact, airborne, or droplet transmission of infectious agents (Siegel et al., 2007). Determinations regarding the level of precautions are based on the potential risk of exposure and the nature of the potential exposure. For example, care of patients with (or suspected of having) diseases with known airborne transmission, such as pulmonary tuberculosis, requires the use of airborne transmission precautions to protect the healthcare worker from exposure and includes the use of respirators (Fennelly, 1998; Jensen et al., 2005).
INTRODUCTION 31 The use of PPE by healthcare workers during the outbreaks of SARS in 2003 has provided a wealth of information on the clinical concerns and challenges resulting from prolonged PPE use due to the risk of expo- sure to a highly contagious agent with substantial potential for morbidity and mortality (e.g., Seto et al., 2003; Lau et al., 2004; Loeb et al., 2004; Yassi et al., 2004). For example, Ofner-Agostini and colleagues (2006) examined hazardous exposure and work practices for 15 healthcare workers who developed SARS. Only nine (60 percent) reported that they had received formal infection prevention and control training. Thirteen of the healthcare workers (87 percent) were unsure of the proper order in which PPE should be donned and doffed. Seven of the healthcare work- ers (41 percent) were involved in the intubation of a patient with SARS. Multiple factors were likely responsible for SARS in these healthcare workers, including the performance of high-risk patient care procedures, the inconsistent use of PPE, fatigue, and lack of adequate infection pre- vention and control training. Studies of the clinical effectiveness of PPE have had mixed results in preventing SARS or respiratory syncytial virus (RSV; Table 1-4). Chal- lenges in studies of this type include the broader context of the use of PPE and difficulties in retrospectively separating the effects of PPE from the effects of other infection control measures. Because PPE works by acting as a barrier to hazardous agents, healthcare workers face challenges in wearing PPE that include difficul- ties in verbal communications and interactions with patients and family members, maintaining tactile sensitivity through gloves, and physiologi- cal burdens such as difficulties in breathing (see Chapter 4). Much re- mains to be learned about the clinical efficacy of healthcare PPE in protecting against various workplace hazards. Innovative approaches are needed to develop standards and products that meet some of the unique needs of the healthcare setting.
32 PREPARING FOR AN INFLUENZA PANDEMIC TABLE 1-4 Studies of the Clinical Effectiveness of PPE During Outbreaks of SARS and RSV Reference Description Results Severe Acute Respiratory Syndrome (SARS) Seto et al., Case-control study in Odds ratio of staff with specific protection 2003 five Hong Kong not getting infected: hospitals of 13 â¢ Masks: OR= 13 (95% CI 3 to 60, p = SARS-infected staff 0.0001) and 241 noninfected â¢ Gloves: OR = 2 (95% CI 0.6 to 7, p = staff 0.364) â¢ Gowns: OR not calculated â¢ Handwashing: OR = 5 (95% CI 1 to 19, p = 0.047) Lau et al., 2004 Case-control study in â¢ Risk of SARS infection in those report- Hong Kong of 72 ing problems with mask fit: OR = 1.00 hospital workers (95% CI 0.51 to 1.95, p = 1.0000) with SARS and 144 â¢ Risk of SARS infection in those who had matched controls problems with fogging of goggles: OR = 0.61 (95% CI 0.31 to 1.17) Loeb et al., Retrospective cohort Risk of acquiring SARS based on use of 2004 study of 43 nurses PPE: working with SARS â¢ Gown: RR = 0.36 (95% CI 0.10 to 1.24, patients in Toronto p = 0.12) critical care units â¢ Gloves: RR = 0.45 (95% CI 0.14 to 1.46, p = 0.22) â¢ N95 (respirator at least once) or surgical mask: RR = 0.23 (95% CI 0.07 to 0.78, p = .02) â¢ N95: RR = 0.22 (95% CI 0.05 to 0.93, p = 0.06) â¢ Surgical mask:a RR = 0.45 (95% CI 0.07 to 2.71, p = 0.56) â¢ N95 vs. surgical mask:b RR = 0.50 (95% CI 0.06 to 4.23, p = 0.51) Teleman et Case-control study in Adjusted odds ratio (multivariate analysis) al., 2004 Singapore of 36 associated with transmission of SARS: healthcare workers â¢ Wearing of N95 mask: 0.1 (95% CI 0.02 with probable SARS to 0.9, p = 0.04) and 50 healthcare â¢ Wearing of gloves: 1.5 (95% CI 0.3 to workers in the same 7.2, p = 0.6) ward with history of â¢ Wearing of gowns: 0.5 (95% CI 0.4 to exposure 6.9, p = 0.6)
INTRODUCTION 33 Reference Description Results Teleman et al., â¢ Handwashing after each patient: 0.07 2004 (contâd) (95% CI 0.008 to 0.7, p = 0.02) Respiratory Syncytial Virus (RSV) Hall and Comparison of use â¢ Proportion of infants acquiring RSV: Douglas, and nonuse of gowns âª During the time masks and gowns 1981 and masks by staff used by staff: 32% members on a pediat- âª During the time masks and gowns not ric ward with chil- used by staff: 41% dren <3 years old â¢ Proportion of staff acquiring RSV: âª During the time masks and gowns used by staff: 33% âª During the time masks and gowns not used by staff: 42% â¢ Measurable benefit not found in control- ling spread of RSV Murphy et al., Prospective study of â¢ Number of RSV or other respiratory in- 1981 use and nonuse of fections did not differ significantly be- masks and gowns by tween the two groups (handwashing staff members caring only; handwashing, gowning, and mask- for infants with res- ing) of staff piratory disease Gala et al., Comparison of use â¢ Frequency of RSV infection in hospital 1986 and nonuse of eye- personnel: nose goggles by staff âª Three weeks during goggle use: 8% members on an infant (p = 0.003) ward âª Three weeks with no goggle use: 34% (p = 0.003) Agah et al., Comparison of use â¢ RSV illness rate in healthcare workers 1987 and nonuse of mask or caring for children with RSV infections: goggles by staff mem- âª Wore masks or goggles: 5% (p < 0.01 bers caring for chil- compared to no masks or goggles dren with RSV category) infections on a pediat- âª Did not wear masks or goggles: 61% ric inpatient service Madge et al., Prospective study of â¢ Combination of cohort nursing with use 1992 four infection control of gowns and gloves significantly re- strategies in prevent- duced RSV infection ing RSV in four â¢ Use of gowns and gloves alone did not pediatric wards result in a significant reduction of infection Continued
34 PREPARING FOR AN INFLUENZA PANDEMIC Reference Description Results Langley et al., Prospective cohort â¢ Various combinations of requirements 1997 study comparing for use of gowns, gloves, and masks did not isolation policies and result in decreased nosocomial rates in pa- RSV infections in tients; gowning for any entry to the patientâs pediatric patients in room was associated with increased risk of nine hospitals RSV transmission NOTE: CI = confidence interval; OR = odds ratio; RR = relative risk. The terms (masks, surgical masks, respirators) used in this table are those used by the investigators or authors of the cited journal article or report. In some cases, it is not pos- sible to determine whether the authorsâ use of the term masks refers to medical masks, respirators, or both. a Comparator is use of no mask. b Consistent use of N95 versus consistent use of surgical mask. Identifying Healthcare PPE: Clarifying the Role of Medical Masks One of the challenges for the healthcare field is to clearly understand the differences among respirators and medical masks as well as their ap- propriate uses. Medical masks (the term is used in this report to encom- pass surgical masks and procedure masks) are loose-fitting coverings of the nose and mouth designed to protect the patient from the cough or ex- haled secretions of the physician, nurse, or other healthcare worker (Ta- ble 1-5). Medical masks are not designed or certified to protect the wearer from exposure to airborne hazards. They may offer some limited, as yet largely undefined, protection as a barrier to splashes and large droplets. However, because of the loose-fitting design of medical masks and their lack of protective engineering, medical masks are not consid- ered PPE. A terminology issue has further confused and blurred the boundary between medical masks and respirators. The term respirator is used in the healthcare field to refer to two different medical devices: (1) the PPE discussed in this report that is used to reduce the wearerâs risk of inhaling hazardous substances and (2) the mechanical ventilator device that is used to maintain the patientâs respiration following endotracheal intuba- tion. This dual (medical and occupational) use of the term respirator has prompted many healthcare workers to refer to PPE respirators as masks, thereby confounding the important distinctions between medical masks and respirators.
INTRODUCTION 35 TABLE 1-5 Comparison of Medical Masks and Respirators Medical Mask Respirator Intended use To protect the patient or Designed to reduce the wearerâs others from the wearerâs inhalation exposure to hazardous expired respiratory drop- airborne particles lets Faceseal fita Not designed to fit to face Designed to fit tightly to face Annual fit test required Fit check Not designed for fit check Recommended with each use requirementsa Certification FDA reviews 510(k) Certified by NIOSH under requirements submission and clears for 42 CFR 84 marketing N95 surgical respirators are NIOSH certified and also reviewed by FDA through a 510(k) submission Available One size generally Some models available in 3 sizes available sizes a Faceseal fit and fit check requirements for respirators apply to tight-fitting respirators and not to loose-fitting powered air-purifying respirators. SOURCE: Adapted from IOM, 2006. Because medical masks are readily available to healthcare workers and are lower in cost than respirators, but are not designed to provide respiratory protection, there is a need to clearly delineate the differences for healthcare management and workers and to consistently use standard terminology. Efforts to achieve definitional clarity are needed, as are dis- tinct and easy-to-understand ratings of the protective effectiveness of the equipment (Chapter 3). Respirators Respirators are personal protective devices that cover the nose and mouth (or in some cases, more of the face and head) and are used to re- duce the wearerâs risk of inhaling hazardous airborne particles (Yassi et al., 2004; see Chapter 3). Respirators are required equipment in the per-
36 PREPARING FOR AN INFLUENZA PANDEMIC formance of a wide range of jobs (e.g., firefighting, automobile painting); as a result, a broad portfolio of respirators have been designed and mar- keted to meet job specifications. Respirators operate either by purifying the air inhaled by the wearer through filtering materials or by independ- ently supplying breathable air to the wearer. Respirators are also catego- rized by their basic design, type of filter, resistance to oil, and degree of filtering efficiency (Box 1-2). The two major issues related to air-purifying respirators are the filter and the fitâthe effectiveness of the filter and the extent to which the respirator has a tight seal with the wearerâs face that restricts inward leakage. In addition, for air-purifying respirators the pressure drop is an important factor regarding the wearability of the respirator. Current fil- ters generally work through electrostatically enhanced filtering media BOX 1-2 Categorizing Respirators Type of Respirators â¢ Air purifying NonpoweredâDepend on the wearer drawing air in through filters or cartridges Powered air-purifying respiratorsâUse a blower to draw air through the filter and deliver it to the wearer â¢ Air supplying Self-contained breathing apparatus Type of Filters â¢ Particulate filters P (oilproof; can survive oil exposure for more than one work shift) R (oil resistant; can be used for oil exposure in one shift) N (not oil resistant; used for oil-free environments) â¢ Gas-vapor respirator â¢ Combination particulate and gas-vapor Filtering Efficiency â¢ Certified for a range of efficiency classes (e.g., 95, 99, 100 percent) Type of Facepiece â¢ Filtering facepieces â¢ Replaceable filter componentsâhalf-mask and full-mask elastomeric respirators â¢ Loose-fitting facepieces Use or nonuse of an exhalation valve
INTRODUCTION 37 and are tested to determine the percentage of the challenge aerosol con- centration that penetrates the filter. To effectively wear most types of air- purifying respirators, prospective wearers must undergo annual fit testing (using qualitative and/or quantitative tests), and they are asked to per- form a fit check with each use of the device (see Chapter 3). Gowns, Gloves, Eye Protection, and Other PPE Protection of the healthcare worker against infectious disease can also involve gloves,6 eye protection, face shields, gowns, and other pro- tection. For the most part, these products are designed to provide a bar- rier to microbial transfer with particular attention to protecting the wearerâs mucous membranes. The extent of liquid penetration (or strike- through) is a major issue with gowns and gloves. Comfort and wearabil- ity issues include the breathability of the fabric or material and biocompatibility or sensitivity to avoid contact dermatitis and other skin irritations (see Chapters 3 and 4). Issues related to viral survival, pene- trance, and reusability remain to be explored as do considerations about how best to integrate the various types of protective equipment to ensure that they work as ensembles (e.g., the respirator and eye protection). Prevention Strategies for Influenza The CDC has developed interim safety recommendations for health- care workers who treat patients in the United States with known or sus- pected avian influenza (CDC, 2004) and has outlined infection control guidelines for the prevention and control of influenza in acute care and other healthcare facilities (CDC, 2007a,b). As additional information becomes available regarding the mechanisms of influenza transmission (Chapter 2), the guidelines will continue to be refined. Until more is known about this issue, all PPE precautions assuming the highest risk level are urged and should be fully supported by healthcare facilities. Influenza precautions emphasize the need for healthcare workers to be vaccinated with the most recent seasonal human influenza vaccine. In addition to providing protection against human influenza, vaccination 6 Hand hygiene is another important and effective component of infection control of respiratory diseases (Ryan et al., 2001; White et al., 2003), but is not in the direct pur- view of this report.
38 PREPARING FOR AN INFLUENZA PANDEMIC also avoids the potential for healthcare workers to be co-infected with both human and avian viruses leading to the potential for viral genetic rearrangement and the emergence of a pandemic strain. CDC recommends that healthcare workers practice standard and droplet infection control precautions for the care of patients infected with human influenza. However, those in contact with patients suspected of having avian influenza are instructed to use additional precautions (such as used for SARS, including airborne precautions and eye protection) because of uncertainty of how the virus may be transmitted between hu- mans. The reasons for additional precautions for avian influenza include the following: â¢ the potential for highly pathogenic avian influenza to cause seri- ous disease and higher death rates may be significantly greater than from human influenza; â¢ each time avian influenza is transmitted to humans, there is an increased chance for the strain to adapt and gain the ability to be trans- ferred more easily to other humans; and â¢ the emergence of a possible pandemic strain could be linked with human-to-human transmission of avian influenza. OVERVIEW OF RELEVANT AGENCIES AND ORGANIZATIONS The testing, regulation, and use of PPE for healthcare workers in- volves a number of government and nongovernmental agencies and or- ganizations. This brief overview is meant to set the context for the report; more details are provided throughout the report, particularly in Chapter 5. In the federal government, occupational health and safety is the re- sponsibility of both the Department of Health and Human Services (DHHS) and the Department of Labor (DoL). The Occupational Safety and Health Act of 1970 created two federal agencies to address worker safety and health: NIOSH (in DHHS) was designated with responsibili- ties for relevant research, training, and education, and OSHA (in DoL) was designated with responsibilities for developing and enforcing work- place safety and health regulations. The NPPTL, created as part of NIOSH in 2000, tests and certifies respirators, and conducts and funds research on improvements in PPE and ensembles used in a variety of occupations. NPPTL also plays an
INTRODUCTION 39 integral role in standards-setting efforts relevant to PPE. Respirators used by workers in OSHA-regulated workplaces, including healthcare work- places, must be NIOSH certified. The criteria used by NIOSH to certify respirators are specified in federal regulations (42 CFR 84); certification testing includes laboratory tests of the filter efficiency of respirators. In addition to work on fit testing, NIOSH is working to address issues re- garding respirator effectiveness through efforts to establish measures of total inward leakage. OSHA regulates the use of PPE products in the workplace. For the most part, OSHA regulations relevant to the use of PPE in healthcare workplaces are the same as those that apply to other industries. The one area of regulation that is particularly pertinent to healthcare workers is the OSHA bloodborne pathogens standard (29 CFR 1910.1030). In addi- tion to requiring that respiratory protection be NIOSH certified, OSHA respirator regulations (29 CFR 1910.134) detail employer responsibilities for establishing and maintaining a comprehensive respiratory protection program, including requirements for a risk assessment to be performed to select the proper respirator, users to be fit tested when tight-fitting facepieces are selected, annual training, users to be medically cleared to wear the device, and a program of inspection, cleaning, and disinfection. OSHA also has a general regulatory standard (29 CFR 1910.132) that governs all other forms of PPE. This regulation details requirements for PPE regarding selection of equipment based on the hazard, proper fit of the equipment, and training for workers as to the hazards present and the safe use of the PPE selected. The federal Occupational Safety and Health Act of 1970 encourages states to develop and operate their own job safety and health programs. Currently 22 states and jurisdictions operate plans that cover both private-sector and state and local govern- ment employees, while 4 states and jurisdictions cover public employees only (OSHA, 2007a). Because respirators, gloves, and gowns used by healthcare workers are considered medical devices (as are medical masks), the FDA (in DHHS) has regulatory authority to provide manufacturers with the ap- proval or clearance to market PPE products for use in health care. Manu- facturerâs data are reviewed by FDA staff to verify that the product does what it claims to do effectively and is not a safety hazard. For most medical devices, the requirements and processes for medical devices to obtain FDA clearance or approval differ considerably from the FDA drug approval process. Pharmaceutical manufacturers are required to submit data from three phases of preclinical and clinical testing prior to consid-
40 PREPARING FOR AN INFLUENZA PANDEMIC eration of any drug for FDA approval. Medical devices are categorized into one of three classes of devices that are subject to differing levels of regulation (see details in Chapter 5). Only the Class III approval process requires the submission of clinical testing data similar to the drug ap- proval process. Other departments, agencies, and organizations also have a role in testing and improving PPE. The Department of Defense is actively in- volved in testing and developing PPE for military applications, including health care. The Department of Homeland Security focuses on emer- gency response PPE and works to coordinate and improve standards and equipment-related issues. The Environmental Protection Agency ad- dresses PPE issues relevant to pesticide exposures and emergency re- sponse readiness. The Consumer Product Safety Commission has oversight responsi- bilities for products sold in the commercial marketplace including PPE. PPE products that assert protection against a specific health hazard must have FDA approval or market clearance. For any other PPE products sold in the commercial marketplace, there are no requirements stipulating pre-market or other testing prior to their sale to the public. For those products that assert NIOSH certification, NIOSH has the authority to act against mislabeled products. FDA, OSHA, and other agencies utilize testing methods and per- formance requirements for PPE that are based on consensus standards developed by voluntary standards-setting organizations such as the Inter- national Organization for Standardization, the American National Stan- dards Institute, and ASTM International (see Chapter 5). FROM CHALLENGES TO OPPORTUNITIES Preparations for an influenza pandemic have heightened the realiza- tion that much remains to be done in order to be adequately prepared to meet this pending public health emergency. Although significant national and worldwide investments have been made in pandemic planning and research, many basic and critical questions remain to be answered. This report focuses on opportunities for answering the questions relevant to providing protection against potential infection of healthcare workers during an influenza pandemic. Technological advances now available can be applied to influenza research and to research on the de- sign and engineering of PPE in order to better meet the needs of the
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INTRODUCTION 45 White, C., R. Kolble, R. Carlson, N. Lipson, M. Dolan, Y. Ali, and M. Cline. 2003. The effect of hand hygiene on illness rate among students in university residence halls. American Journal of Infection Control 31(6):364-370. WHO (World Health Organization) 2005. WHO global influenza preparedness plan: The role of WHO and recommendations for national measures before and during pandemics. http://www.who.int/csr/resources/publications/influ- enza/GIP_2005_5Eweb.pdf (accessed June 11, 2007). Yassi, A., E. Bryce, D. Moore, R. Janssen, R. Copes, K. Bartlett, M. Fitzgerald, M. Gilbert, P. Bigelow, Q. Danyluk, et al. 2004. Protecting the faces of health care workers: Knowledge gaps and research priorities for effective protection against occupationally-acquired respiratory infectious diseases. British Columbia, Canada: The Change Foundation. http://www.cher.ubc.ca/PDFs/ Protecting_Faces_Final_Report.pdf (accessed June 11, 2007).