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

Abstract

The strategy in New Zealand (Aotearoa) to eliminate coronavirus disease requires that international arrivals undergo managed isolation and quarantine and mandatory testing for severe acute respiratory syndrome coronavirus 2. Combining genomic and epidemiologic data, we investigated the origin of an acute case of coronavirus disease identified in the community after the patient had spent 14 days in managed isolation and quarantine and had 2 negative test results. By combining genomic sequence analysis and epidemiologic investigations, we identified a multibranched chain of transmission of this virus, including on international and domestic flights, as well as a probable case of aerosol transmission without direct person-to-person contact. These findings show the power of integrating genomic and epidemiologic data to inform outbreak investigations.

Keywords: COVID-19; New Zealand; SARS-CoV-2; air travel; border quarantine; case-patients; coronavirus; coronavirus disease; respiratory infections; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.

Figure 1

Sequence of probable transmission events and associated relevant locations in-flight and MIQ for severe acute respiratory syndrome coronavirus 2 during border quarantine and air travel, New Zealand, September 2020. Location of case A is approximate (Table). COVID-19, coronavirus disease; MIQ, managed isolation and quarantine.

Figure 2

Phylogenetic trees showing genomic relationship of severe acute respiratory syndrome coronavirus 2 genomes generated for 9 case-patients, New Zealand, September 2020. Shown are number of mutations, as well as the F.1 cluster (red) within the context of the closest ancestral B.1.36.17 lineage (black). Scale bar indicates nucleotide substitutions per site. MIQ, managed isolation and quarantine.