An aerosol-generating procedure (AGP) is a medical or health-care procedure that a public health agency such as the World Health Organization or the United States Centers for Disease Control and Prevention (CDC) has designated as creating an increased risk of transmission of an aerosol borne contagious disease,[1] such as COVID-19. The presumption is that the risk of transmission of the contagious disease from a patient having an AGP performed on them is higher than for a patient who is not having an AGP performed upon them. This then informs decisions on infection control, such as what personal protective equipment (PPE) is required by a healthcare worker performing the medical procedure, or what PPE healthcare workers are allowed to use.
Designation of a procedure as an AGP may indicate a presumption that such a procedure causes the emission of more aerosols than a patient not undergoing the procedure. Such a position is at increasing odds with the scientific understanding of bioaerosol production and airborne transmission of respiratory infections.[2][3][4][5] At times, healthcare workers concerned about their own risk of contracting airborne infections have been denied access to respirators outside the employment of AGPs.[6]
Medical procedures that have been designated as AGPs include positive-pressure mechanical ventilation including BiPAP and continuous positive airway pressure (CPAP), high-frequency ventilation, tracheal intubation,[7] airway suction, tracheostomy, chest physiotherapy, nebuliser treatment, sputum induction, bronchoscopy[8] and ultrasonic scaling and root planing. Different public health agencies have different lists of AGPs.[1] The term AGP became popular during the 2003 SARS epidemic, where small retrospective studies showed a higher rate of infection amongst healthcare workers in which the AGPs were performed.
:1 was invoked but never defined (see the help page).Small size droplets (< 1 μm) predominated the total number of droplets expelled when coughing
These observations confirm that there is a substantial probability that normal speaking causes airborne virus transmission in confined environments.
Given the lack of evidence for droplet and fomite transmission and the increasingly strong evidence for aerosols in transmitting numerous respiratory viruses, we must acknowledge that airborne transmission is much more prevalent than previously recognized.
The existing guidelines said health providers working around COVID-19 patients should wear a surgical mask. It restricted use of the more protective P2 or N95 masks, which stop airborne particles getting through, to very limited scenarios. These involved "aerosol-generating procedures", such as inserting a breathing tube.