Background

Historical themes of infection prevention and control (IPC) in emergency medical services (EMS) have classically centered around hand hygiene, disinfection of surfaces, sharps safety, personal protective equipment (PPE), and the disinfection of equipment. EMS clinicians often have contact with multiple patients per day, in home, ambulance, and hospital environments, while 911 telecommunicators have varying degrees of contact with EMS clinicians. The transition of patients throughout these environments and the challenges of hand washing and personal protection in the field provide opportunities for pathogens to spread among EMS clinicians and 911 telecommunicators.¹ For the purposes of this Technical Brief, the EMS and 911 workforce is defined as the personnel primarily involved in medical care, including telecommunicators who support delivery of care,

Many infectious agents can be transmitted via contact with the skin or mucous membranes; despite this, compliance with hand hygiene measures has been less than optimal.² Viruses such as norovirus can be spread by contact and possibly through airborne exposure after emesis. In Nevada, EMS clinicians wore gloves during 56 percent of activations, washed hands after 27 percent of patient encounters, and disinfected equipment 31 percent of the time.³ In Maine, one study suggested that half of ambulances tested positive for methicillin-resistant Staphylococcus aureus (MRSA) in high action areas.⁴ Another study showed that 57 percent of reusable ambulance equipment tested positive for blood.⁵ Yet another study reported that current decontamination practices may not reduce viral load on ambulance surfaces.⁶

Other infectious agents, such as the human immunodeficiency virus (HIV) and hepatitis C, can spread to EMS clinicians via blood-borne exposure. EMS clinicians have an increased risk of injury from needle sticks or other sharp instruments because of the difficulty of performing procedures in a mobile environment.⁷ Hepatitis B can be spread via blood-borne exposure, and many EMS clinicians are required to be vaccinated against it. Yet, studies have shown that EMS clinicians frequently do not follow recommendations for minimizing the risk of needle stick injuries.⁸

The EMS and 911 workforces are also at risk for airborne exposure to infectious diseases, such as tuberculosis, influenza, and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The risk of airborne exposure is increased by not consistently using appropriate respiratory and eye/face protection.⁷

The coronavirus disease 2019 (COVID-19) pandemic has highlighted the importance of IPC practices. However, adherence to IPC guidance involves structural determinants such as public health policy and budgetary support as well as individual knowledge, attitudes, education, skills, and behaviors. The resulting decisional dilemmas that emerge include addressing reasons for decreased adherence to IPC standards by EMS clinicians and 911 telecommunicators, and implementing effective IPC at the individual and system levels.

Barriers to research in the prehospital field contribute to the limitations of the science in EMS today. Study design and data collection challenges arise from the mobile work environment and multiple care sites such as homes, streets, outdoor settings, and the hospital. Previous research into IPC for EMS clinicians has been heterogenous and often qualitative in nature given these barriers to experimental design and quantitative data collection in the field environment. Some previous PPE research may be relevant to EMS clinicians, but this is subject to the limitations related to changes in work environment, movement, exertion, and safety concerns.

The Office of Emergency Medical Services at the U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) requested this Technical Brief for the purpose of summarizing the evidence on: exposures to and incidence/prevalence/severity of infectious diseases in the EMS and 911 workforces; and interventions for preventing, recognizing, and controlling occupationally acquired infectious diseases in the EMS and 911 workforces. This brief should be useful to policy makers, researchers, and managers in the EMS and 911 field in making decisions about how to minimize the risk of infectious diseases in the EMS and 911 workforces. The Technical Brief should help to identify future research needs by identifying research questions that have not been addressed in the literature.

Guiding Questions

1. What are the characteristics, incidence, prevalence, and severity of occupationally acquired infectious diseases and related exposures for the EMS and 911 workforces?

   1. How do the incidence, prevalence, and severity of infectious diseases and related exposures vary by demographic characteristics (e.g., age, sex, race, ethnicity) of the workforce?
   2. How do the incidence, prevalence, and severity of infectious diseases and related exposures vary by workforce characteristics (e.g., training, experience, level of practice, geographic region)?
2. What are the characteristics and reported effectiveness (i.e., benefits and harms) of practices to prevent infectious diseases?

   1. How do workforce practices to prevent infectious diseases vary by demographic characteristics (e.g., age, sex, race, ethnicity)?
   2. How do workforce practices to prevent infectious diseases vary by workforce characteristics (e.g., level of training, experience, geographic region)?
   3. How do workforce practices to prevent infectious diseases vary by practice characteristics (e.g., specific types of training incorporated into practice, PPE, personnel, and budget requirements)?
   4. What is the reported effectiveness (i.e., benefits and harms) in studies of EMS and 911 workforce practices to prevent infectious diseases? (Outcomes of interest include but are not limited to, incidence, prevalence, duration, severity, missed work, healthcare utilization, separation from the workforce, disability, and death from infections.)
3. What are the characteristics and reported effectiveness (i.e., benefits and harms) of practices examined in studies of the EMS and 911 workforces to recognize and control (e.g., chemoprophylaxis, but excluding treatment) infectious diseases?

   1. How do workforce practices to recognize and control infectious diseases vary by demographic characteristics (e.g., age, sex, race, ethnicity) of the EMS and 911 workforces?
   2. How do workforce practices to recognize and control infectious diseases vary by workforce characteristics (e.g., level of training, experience, level of practice, geographic region)?
   3. How do workforce practices to recognize and control infectious diseases vary by infection recognition and control practice characteristics (e.g., specific types of training incorporated into practice, PPE, personnel, and budget requirements)?
   4. What is the reported effectiveness (i.e., benefits and harms) in studies of EMS and 911 workforce practices to recognize and control infectious disease? (Outcomes of interest include but are not limited to, incidence, prevalence, duration, severity, missed work, healthcare utilization, separation from the workforce, disability, and death from infections.)
4. What are the context and implementation factors of studies with effective EMS and 911 workforce practices to prevent, recognize, and treat occupationally acquired infectious diseases? This description might include distinguishing factors such as workforce training, surveillance, protective equipment, pre- and post-exposure prophylaxis, occupational health services, preparedness for emerging infectious diseases, and program funding.
5. What future research is needed to close existing evidence gaps regarding preventing, recognizing, and treating occupationally acquired infectious diseases in the EMS and 911 workforces?

For Guiding Question 1, we defined occupationally acquired exposures to infectious diseases as contact exposure (intact skin), respiratory exposure (inhaled and aerosolized), and blood-borne exposure (needle sticks, blood to non-intact skin, etc.). Organisms of interest included but are not limited to MRSA, SARS-CoV-2, influenza, tuberculosis, HIV, and hepatitis B and C. We considered the 911 workforce to include the 911 telecommunicators who are fielding the calls and interacting with EMS clinicians. The EMS workforce includes the responding healthcare personnel in field settings. We developed a conceptual framework to guide work on the Technical Brief (Figure 1).

Figure 1

Conceptual framework for infection prevention and control in EMS and 911 workers. EMS = emergency medical services; IPC = infection prevention and control; GQ = Guiding Question; PPE = personal protective equipment