Journal article

A quantitative assessment of the efficacy of surgical and N95 masks to filter influenza virus in patients with acute influenza infection.

DF Johnson, JD Druce, C Birch, ML Grayson

Clin Infect Dis | Published : 2009

Abstract

We assessed the in vivo efficacy of surgical and N95 (respirator) masks to filter reverse transcription-polymerase chain reaction (RT-PCR)-detectable virus when worn correctly by patients with laboratory-confirmed acute influenza. Of 26 patients with a clinical diagnosis of influenza, 19 had the diagnosis confirmed by RT-PCR, and 9 went on to complete the study. Surgical and N95 masks were equally effective in preventing the spread of PCR-detectable influenza.