tetano
Editor, Senior Moderator
Build Environ
. 2022 Aug 1;221:109328.
doi: 10.1016/j.buildenv.2022.109328. Epub 2022 Jun 26.
Increasing contributions of airborne route in SARS-CoV-2 omicron variant transmission compared with the ancestral strain
Shuyi Ji[SUP] 1 [/SUP], Shenglan Xiao[SUP] 2 [/SUP], Huaibin Wang[SUP] 2 [/SUP], Hao Lei[SUP] 1 [/SUP]
Affiliations
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has become the dominant lineage worldwide. Experimental studies have shown that SARS-CoV-2 Omicron variant is more stable on various environmental surfaces than the ancestral strains of SARS-CoV-2. However, the influences on the role of the contact route in SARS-CoV-2 transmission are still unknown. In this study, we built a Markov chain model to simulate the transmission of the Omicron and ancestral strains of SARS-CoV-2 within a household over a 1-day period from multiple pathways; that is, airborne, droplet, and contact routes. We assumed that there were two adults and one child in the household, and that one of the adults was infected with SARS-CoV-2. We assumed two scenarios. (1) Asymptomatic/presymptomatic infection, and (2) symptomatic infection. During asymptomatic/presymptomatic infection, the contact route contributing the most (37%-45%), followed by the airborne (34%-38%) and droplet routes (21%-28%). During symptomatic infection, the droplet route was the dominant pathway (48%-71%), followed by the contact route (25%-42%), with the airborne route playing a negligible role (<10%). Compared to the ancestral strain, although the contribution of the contact route increased in Omicron variant transmission, the increase was slight, from 25%-41% to 30%-45%. With the growing concern about the increase in the proportion of asymptomatic/presymptomatic infection in Omicron strain transmissions, the airborne route, rather than the fomite route, should be of focus. Our findings suggest the importance of ventilation in the SARS-CoV-2 Omicron variant prevention in building environment.
Keywords: Airborne; Ancestral strains; Contact; Markov chain model; Omicron variant.
. 2022 Aug 1;221:109328.
doi: 10.1016/j.buildenv.2022.109328. Epub 2022 Jun 26.
Increasing contributions of airborne route in SARS-CoV-2 omicron variant transmission compared with the ancestral strain
Shuyi Ji[SUP] 1 [/SUP], Shenglan Xiao[SUP] 2 [/SUP], Huaibin Wang[SUP] 2 [/SUP], Hao Lei[SUP] 1 [/SUP]
Affiliations
- PMID: 35784591
- PMCID: PMC9233747
- DOI: 10.1016/j.buildenv.2022.109328
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has become the dominant lineage worldwide. Experimental studies have shown that SARS-CoV-2 Omicron variant is more stable on various environmental surfaces than the ancestral strains of SARS-CoV-2. However, the influences on the role of the contact route in SARS-CoV-2 transmission are still unknown. In this study, we built a Markov chain model to simulate the transmission of the Omicron and ancestral strains of SARS-CoV-2 within a household over a 1-day period from multiple pathways; that is, airborne, droplet, and contact routes. We assumed that there were two adults and one child in the household, and that one of the adults was infected with SARS-CoV-2. We assumed two scenarios. (1) Asymptomatic/presymptomatic infection, and (2) symptomatic infection. During asymptomatic/presymptomatic infection, the contact route contributing the most (37%-45%), followed by the airborne (34%-38%) and droplet routes (21%-28%). During symptomatic infection, the droplet route was the dominant pathway (48%-71%), followed by the contact route (25%-42%), with the airborne route playing a negligible role (<10%). Compared to the ancestral strain, although the contribution of the contact route increased in Omicron variant transmission, the increase was slight, from 25%-41% to 30%-45%. With the growing concern about the increase in the proportion of asymptomatic/presymptomatic infection in Omicron strain transmissions, the airborne route, rather than the fomite route, should be of focus. Our findings suggest the importance of ventilation in the SARS-CoV-2 Omicron variant prevention in building environment.
Keywords: Airborne; Ancestral strains; Contact; Markov chain model; Omicron variant.
