As Wuhan, the Chinese city where the COVID-19 pandemic began, revs up a massive testing campaign, some residents crowding the test centres expressed concern on Saturday that the very act of getting tested could expose them to the coronavirus.

Safety has become a hot topic on social media groups among the 11 million residents of Wuhan, people said as they converged on open-air test sites at clinics and other facilities. Many said, though, that they support the voluntary campaign.

Wuhan health authorities sprang back into action after confirming last weekend the central Chinese city's first cluster of new infections since it was released from virtual lockdown on April 8.