Many healthcare professionals were exposed to the 2009 H1N1 influenza virus during the first wave of the pandemic because they were not using respiratory protection and/or other pieces of personal protective equipment (PPE). David B. Banach MD, MPH, of the Department of Medicine at Mount Sinai School of Medicine in New York, and colleagues, suggest that unprotected exposures tended to be more frequent among healthcare workers caring for patients with atypical clinical presentations.
Banach and colleagues conducted a study in a large teaching hospital in New York City in which a screening protocol was introduced in early April 2009 to identify patients presenting to the Emergency Department (ED)Â and other locations with influenza-like illness (ILI). The protocol was designed to rapidly identify cases in order to minimize the risk of influenza transmission by implementing infection prevention precautions (including cough etiquette, physical separation, and use of appropriate PPE) by personnel providing care to the patient. The researchers report that healthcare worker contact investigations were performed for all patients with confirmed 2009 H1N1 infection, and unprotected exposure was defined as providing care within six feet of a patient without using PPE.
The researchers reviewed all unprotected healthcare worker exposures between May 22 and July 6, 2009, and examined infection control records to identify patients admitted from the ED who were confirmed to have 2009 H1N1 infection. Information about the healthcare worker exposures was obtained from contact investigation records. During the study period, 44 ED patients had 2009 H1N1 infection diagnosed and 37 met the definition for presence of ILI. Twenty-six patients were involved in one or more unprotected HCW exposures. A total of 277 unprotected exposures were identified. The researchers report that the location of unprotected healthcare worker exposures included the ED (57 percent), inpatient units (41 percent) and other locations (2 percent). Exposures involved 41 percent of nurses, 32 percent of physicians and 17 percent of ED technicians and patient care assistants on inpatient units.
The researchers note, "The identification of almost five unprotected healthcare exposures for each patient who presented with ILI was a more unexpected finding. Potential explanations include inconsistent use of the screening and isolation protocol, communication barriers, and suboptimal adherence to recommended PPE use. Each of these warrants further research. Previous studies have demonstrated that healthcare worker compliance with respiratory protection guidance, including that related to influenza, is generally poor. A recent study of healthcare workers opinions about respirator use identified the need for new equipment that better meets the needs of healthcare workers."
Banach, et al. add, "Since substantial numbers of unprotected exposures occurred during this period of heightened awareness of influenza and at a time when vaccination was not an option, it is likely that similar or perhaps even more exposures occur during typical influenza seasons. This highlights the importance of healthcare worker immunization, when available, and the need for a better understanding of barriers to effective implementation of screening protocols and adherence to recommended respiratory PPE use among healthcare workers."
Their research was published in Infection Control and Hospital Epidemiology.
Reference: Banach DB, Bielang R and Calfee DP. Factors Associated with Unprotected Exposure to 2009 H1N1 Influenza A among Healthcare Workers during the First Wave of the Pandemic. Infect Control Hosp Epidem. Vol. 32, No. 3. March 2011.
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