Travelers infected one another across hallway in Covid-19 quarantine facility, New Zealand research shows

A traveler isolated for Covid-19 at a quarantine facility in New Zealand managed to infect three others across a hallway, researchers reported Thursday.

Closed-circuit camera footage, genetic testing and careful contact tracing show that the only conceivable way the virus could have passed from one room to another was in air that leaked out when both doors were briefly opened, the researchers said.

It's a demonstration of how the virus can spread -- and of how well vaccines can work. The one person who escaped infection was fully vaccinated and never tested positive, despite having stayed in the same room as four other infected people for weeks on end.