Covid: Why Australia's 'world-class' quarantine system has seen breaches

 Australia's hotel quarantine system has been an extremely effective first line of defence against Covid-19.

The country has largely eliminated the virus, often going weeks without a locally acquired infection. Hotel quarantine is credited a huge part of that success.

But a series of isolated local cases in recent months - all from hotel quarantine leaks - have caused alarm.

Since November, three cities have entered snap lockdowns on the back of such infections, aiming to halt outbreaks at their source.

https://www.bbc.com/news/world-australia-55929180