Masks for Prevention of Influenza Transmission in Acute and Long-Term Care Settings: A Review of Clinical Effectiveness, Cost-Effectiveness and Guidelines [Internet]

Excerpt

Influenza is a viral respiratory infection causing fever, cough, and general aches and pain. Annual vaccination for select high-risk populations, including health care workers (HCW) and other people in contact with those at high risk of influenza, is recommended.^– Transmission of influenza between infected HCWs and their vulnerable patients can result in morbidity and mortality.

Some HCWs are not vaccinated against influenza. In a 2011 Canadian systematic review (SR) of studies from Australia, Canada, Finland, Germany, Thailand, United Kingdom, and the United States of America, the influenza incidence rate amongst unvaccinated HCWs (in any type of care setting) was reported to be 18.69 (95% confidence interval = 15.80 to 22.11) per 100 population, per season. In such instances, personal protective equipment (PPE) such as surgical masks and procedural masks are used to minimize exposures. However, there is uncertainty as to the evidence regarding the clinical effectiveness of masks at preventing the transmission of influenza between unvaccinated HCWs and patients.

Previous CADTH reports on this topic include a 2017 Summary with Critical Appraisal on the use of respirators for protection against droplet borne illness, a 2014 Summary with Critical Appraisal on the use of respiratory precautions for protection from infectious agents, and a 2011 Technology Report on physical interventions to interrupt or reduce the spread of respiratory viruses. The objective of the present report is to investigate the clinical effectiveness, cost-effectiveness, and evidence-based guidelines regarding the use of masks for unvaccinated HCWs to prevent the transmission of influenza in acute or long-term care settings.