Scientists plot path for travel bubble

A trans-Tasman travel bubble could be run safely without the need for quarantine, scientists have found in a study.

Published as New Zealand discovered Covid-19 in two travellers who left quarantine early, the study has revealed that airport screening at both ends of a flight, two post-arrival tests, mask wearing and contact tracing could heavily reduce the risk of outbreaks.

The research found such measures would reduce the risk of the virus arriving in a Covid-free New Zealand to about the same level as properly run quarantining. It was done by Otago University Professors Nick Wilson and Michael Baker, and Professor Martin Eichner from Germany’s Tuebingen University.

‘‘Our analysis shows that there is potential to replace this quarantine period with multi-layered interventions... that would also maintain a low risk of importing the pandemic virus,’’ the scientists said.

‘‘Whatever approach is chosen, careful management and will be needed.’’

The scientists’ risk assessment was based on screening passengers with a thermal camera and a questionnaire about symptoms on exit and arrival.

Passengers would need to be tissue tested for the virus three days and 12 days after arrival, wear masks on the plane and until the second test result, and self-report any symptoms. Contact tracing would need to be in place.

evaluation

Such measures would equal a theoretical risk of one Covid outbreak in New Zealand each 30 years, if there was one flight from Australia daily and a low level of cases in that country.

This compares with a risk of one outbreak in 34 years with mask wearing on flights, screening on arrival and 14 days quarantine. Calculations based on 10 times as many cases in Australia or 10 flights arriving each day would each increase the risk ten-fold.