Antarctica’s biggest Covid outbreak yet puts US station McMurdo on pause

Antarctica’s largest-yet outbreak of Covid-19 has left 10% of personnel in its largest station infected and the US pausing all inward travel.

Infections have swept through US-run McMurdo station, the largest base in Antarctica. The National Science Foundation said it had recorded 98 positive tests since the beginning of October from a total population of 993.

The foundation was “moving to lower the density of the population to reduce the possibility of transmission” and had implemented a pause on all travel to the continent for the next two weeks to “reassess the situation”.

The outbreak comes as stations are gearing up for their maximum-capacity summer field season, where many scientists fly in to conduct two to three months of research. For a number of bases, this year marked the first full season of Antarctic research after two years of Covid-19 disruption. It is not yet clear what effect the pause on travel will have on research projects.

The Covid outbreak is not Antarctica’s first but appears to be the largest. In December 2020 the first cases were detected, with 36 people testing positive at Chile’s base. A year later an outbreak infected 11 of the 30 people in Belgian research station Princess Elisabeth, and in January 2022 there were 24 cases detected in an outbreak at Argentina’s Esperenza base.

Of the 64 active cases, “most have mild symptoms and are isolating in their rooms”, the NSF said. In an effort to contain the breakout and stop it spreading further, the NSF will be requiring residents to spend five days in isolation before transiting to the south pole or deep field, and recommending KN-95 masks be worn at all times.

Those testing positive will be required to isolate for five days, then mask an additional five days, and can return to work after two negative tests.