tetano
Editor, Senior Moderator
Risk Anal
. 2023 Nov 7.
doi: 10.1111/risa.14249. Online ahead of print. A COVID-19 cluster analysis in an office: Assessing the long-range aerosol and fomite transmissions with infection control measures
Atsushi Mizukoshi[SUP] 1 [/SUP], Jiro Okumura[SUP] 1 [/SUP], Kenichi Azuma[SUP] 1 [/SUP]
Affiliations
Simulated exposure to severe acute respiratory syndrome coronavirus 2 in the environment was demonstrated based on the actual coronavirus disease 2019 cluster occurrence in an office, with a projected risk considering the likely transmission pathways via aerosols and fomites. A total of 35/85 occupants were infected, with the attack rate in the first stage as 0.30. It was inferred that the aerosol transmission at long-range produced the cluster at virus concentration in the saliva of the infected cases on the basis of the simulation, more than 10[SUP]8[/SUP] PFU mL[SUP]-1[/SUP] . Additionally, all wearing masks effectiveness was estimated to be 61%-81% and 88%-95% reduction in risk for long-range aerosol transmission in the normal and fit state of the masks, respectively, and a 99.8% or above decline in risk of fomite transmission. The ventilation effectiveness for long-range aerosol transmission was also calculated to be 12%-29% and 36%-66% reductions with increases from one air change per hour (ACH) to two ACH and six ACH, respectively. Furthermore, the virus concentration reduction in the saliva to 1/3 corresponded to the risk reduction for long-range aerosol transmission by 60%-64% and 40%-51% with and without masks, respectively.
Keywords: COVID-19; SARS-CoV-2; fomite transmission; long-range aerosol transmission; risk assessment.
. 2023 Nov 7.
doi: 10.1111/risa.14249. Online ahead of print. A COVID-19 cluster analysis in an office: Assessing the long-range aerosol and fomite transmissions with infection control measures
Atsushi Mizukoshi[SUP] 1 [/SUP], Jiro Okumura[SUP] 1 [/SUP], Kenichi Azuma[SUP] 1 [/SUP]
Affiliations
- PMID: 37936539
- DOI: 10.1111/risa.14249
Simulated exposure to severe acute respiratory syndrome coronavirus 2 in the environment was demonstrated based on the actual coronavirus disease 2019 cluster occurrence in an office, with a projected risk considering the likely transmission pathways via aerosols and fomites. A total of 35/85 occupants were infected, with the attack rate in the first stage as 0.30. It was inferred that the aerosol transmission at long-range produced the cluster at virus concentration in the saliva of the infected cases on the basis of the simulation, more than 10[SUP]8[/SUP] PFU mL[SUP]-1[/SUP] . Additionally, all wearing masks effectiveness was estimated to be 61%-81% and 88%-95% reduction in risk for long-range aerosol transmission in the normal and fit state of the masks, respectively, and a 99.8% or above decline in risk of fomite transmission. The ventilation effectiveness for long-range aerosol transmission was also calculated to be 12%-29% and 36%-66% reductions with increases from one air change per hour (ACH) to two ACH and six ACH, respectively. Furthermore, the virus concentration reduction in the saliva to 1/3 corresponded to the risk reduction for long-range aerosol transmission by 60%-64% and 40%-51% with and without masks, respectively.
Keywords: COVID-19; SARS-CoV-2; fomite transmission; long-range aerosol transmission; risk assessment.