Incidence of Respiratory Illness in Outpatient Healthcare Workers Who Wear Respirators or Medical Masks While Caring for Patients

Prevention strategies are key in limiting the transmission of respiratory viruses such as influenza. Among non-pharmacologic interventions, there is intense interest in the use of facial protective equipment (FPE) - medical masks (MM) or N95 respirators (N95) - as a key component of personal protective equipment (PPE) when faced with respiratory illness including influenza. However, their relative protective effect is unknown, especially in the outpatient setting (OPD). To plan for future epidemics and best manage limited supplies of FPE, evidence is needed to guide planning activities and policy makers. This project aims to answer a key question: How do N95s protect healthcare workers (HCWs) in the OPD against influenza, influenza-like illness (ILI), acute respiratory illness (ARI) and other causes of respiratory illnesses including respiratory viral illness (RV), as compared to MMs? The study outcomes are to:

• determine the most effective FPE equipment to use to prevent disease transmission in the OPD during an influenza outbreak, epidemic or pandemic event.
• the incidence of organism-specific rates of ARI in the OPD during the RV season.
• the incidence rate of organism-specific respiratory viral infections in the OPD.

Clinics (or their functional partitions) will be randomized into either the N95 or MM arm using a stratified randomization scheme to ensure comparability between the two arms. All participants, regardless of study arm, will be fit-tested for an N95. The study will require a 16-18 week period that will be initiated when viral surveillance data indicates that influenza season has begun. Participants will be recruited through informational meetings with clinic staff. Participants will have blood drawn before week 1 and after the end of the active portion of the study to assess seroconversion over the study period to capture the incidence of non-symptomatic influenza. All participants will fill out a pre-study survey and post on knowledge, attitudes and beliefs regarding influenza, influenza vaccinations, and appropriate PPE.

During the first week, participants will fill out a form with basic demographic and workplace information. Participants will be asked to 1. wear participant's appropriate FPE when in close contact with patients with suspected or confirmed influenza or RV for the next 12-16 weeks; 2. fill out a daily form assessing exposure to ILI and FPE use, and weekly forms assessing RV symptoms and medication use. The investigators will collect nasal and throat (pharyngeal) swabs twice during the study for all participants, and when participants report having an ILI or ARI. Study staff will make unannounced visits to the clinics to observe FPE and hand hygiene compliance rates.

Participants will be compensated for participation (as detailed below). To be included the clinical site leadership has agreed to have one of more participants in the trial. To be included the subject(s): (1) meets the definition of "healthcare personnel" (2) is able to read and sign informed consent (3) agrees to all requirements of the protocol, including fit testing and diary keeping (4) is 18 years old or greater (6) passes fit testing for one of the study supplied N95 and agrees to use that model for the entire 16 week period of the study. Subjects are excluded if: (1) subject self-identified as having severe heart, lung, neurological or other systemic disease that one or more Investigator believes could preclude safe participation (2) are known to not tolerate wearing FPE for any period (3) facial hair, or other issue such as facial adornments, preclude respirator Occupational Safety and Health Administration (OSHA)-compliant fit testing or proper mask fit during the study period (4) subjects are advised by Occupational Health (or other qualified clinician) to not wear the same or similar respirator or medical mask models used in this study (5) in the opinion of the Investigator, may not be able to reasonably participate in the trial for any reason (6) Self-identified as in, or will be in the third trimester of pregnancy, during the study period.