Hundreds of people would have been spared COVID-19 if all passengers and crew from the Diamond Princess cruise ship were immediately evacuated instead of forced to stay onboard in quarantine, according to new modelling.

Rather than reducing the incidence of the virus as intended, the floating quarantine resulted in an initial infection rate that was four times higher than in the epicentre in Wuhan, researchers from the Umea University, Sweden, report in the Journal of Travel Medicine.

Their modelling shows that just 76 people would have been affected if everyone onboard had been evacuated earlier and allowed to undergo quarantine in their home countries.

This is well below the 619 (17% of all onboard) who tested positive for coronavirus after being quarantined on the ship for two weeks.