BACKGROUND: The potential for aerosol transmission of @entity778 (ie, in healthcare facilities) is controversial. We constructed a simulated @entity1 examination room that contained coughing and breathing manikins to determine whether coughed @entity683 was infectious and assessed the effectiveness of an N95 respirator and surgical mask in blocking transmission. METHODS: National Institute for Occupational Safety and Health aerosol samplers collected size-fractionated aerosols for 60 minutes at the mouth of the breathing manikin, beside the mouth, and at 3 other locations in the room. Total recovered virus was quantitated by quantitative polymerase chain reaction and infectivity was determined by the viral plaque assay and an enhanced infectivity assay. RESULTS: Infectious @entity683 was recovered in all aerosol fractions (5.0% in >4  m aerodynamic diameter, 75.5% in 1-4  m, and 19.5% in <1  m; n = 5). Tightly sealing a mask to the face blocked entry of 94.5% of total virus and 94.8% of infectious virus (n = 3). A tightly sealed respirator blocked 99.8% of total virus and 99.6% of infectious virus (n = 3). A poorly fitted respirator blocked 64.5% of total virus and 66.5% of infectious virus (n = 3). A mask documented to be loosely fitting by a PortaCount fit tester, to simulate how masks are worn by healthcare workers, blocked entry of 68.5% of total virus and 56.6% of infectious virus (n = 2). CONCLUSIONS: These results support a role for aerosol transmission and represent the first reported laboratory study of the efficacy of masks and respirators in blocking inhalation of @entity683 in aerosols. The results indicate that a poorly fitted respirator performs no better than a loosely fitting mask.

Detection of XXXX in cough aerosols generated in a simulated @entity1 examination room.

@entity1 :: ('9606', 'Species') :: ['patient'] @entity778 :: ('MESH:D015658', 'Disease') :: ['infectious influenza virus'] @entity683 :: ('MESH:D007251', 'Disease') :: ['influenza']
@entity778 :: (MESH:D015658,Disease) :: ['infectious influenza virus']
