Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 during Border Quarantine and Air Travel, New Zealand (Aotearoa)

“…In the case-control study results, we found no significant differences between cases and controls in reported personal protective measures, including hand hygiene, masking, physical distancing, and no close contact interactions, were reported. No mechanical ventilation was identified in the mail room or laundry room, which could be areas of the building with increased risk for transmission of COVID-19 due to poor ventilation [24][25][26]. However, the reported use of shared spaces, including the mail and laundry rooms, did not differ significantly between cases and controls in our investigation.…”

“…However, we note that depending on the ventilation settings for the space, the environmental conditions (e.g., temperature, relative humidity), or the biological properties of the airborne pathogen itself, susceptible individuals are also exposed to a (potentially nonnegligible) residual risk even after the infector(s) leave(s) the room, if they remain in situ. For example, a recent study reported evidence to suggest COVID-19 transmission in a shared bathroom between an infectious individual and a susceptible one who entered up to 40 minutes after the infector had left (Jung et al, 2021) and we see further evidence of transmission between neighbouring zones through connected airflow (Eichler et al, 2021;Jung et al, 2021;SAGE, 2021) demonstrating the possibility of airborne transmission despite the absence of an infector.…”

“…Outside of Hong Kong, opening doors for testing or meal collection have also been noted as common risk factors associated with HQ transmission despite strict protocols to reduce such risks. 9 , 11 In our study, data on proximity or other risk factors could have provided additional evidence to support identified instances of HQ transmission or support excluded instances lacking genomic data.…”