Chinese authorities are preparing to test 11 million people in Wuhan after a small outbreak this week.
The city in Hubei province, where the virus is believed to have originated with the first recorded cases, had reported few daily cases since early March and none since early April, until a cluster of six was confirmed at the weekend.
The World Health Organization (WHO) guidance on face masks has remained consistent during the coronavirus pandemic. It has stuck to the line that masks are for healthcare workers – not the public.
“Wearing a medical mask is one of the prevention measures that can limit the spread of certain respiratory viral diseases, including Covid-19. However, the use of a mask alone is insufficient to provide an adequate level of protection, and other measures should also be adopted,” the WHO has stated.
Nevertheless, as some countries have eased lockdown conditions, they have been making it mandatory to wear face coverings outside, as a way of trying to inhibit spread of the virus. This is in the belief that the face covering will prevent people who cough and sneeze ejecting the virus any great distance.
There is no robust scientific evidence – in the form of trials – that ordinary masks block the virus from infecting people who wear them. There is also concerns the public will not understand how to use a mask properly, and may get infected if they come into contact with the virus when they take it off and then touch their faces.
Also underlying the WHO’s concerns is the shortage of high-quality protective masks for frontline healthcare workers.
Nevertheless, masks do have a role when used by people who are already infected. It is accepted that they can block transmission to other people. Given that many people with Covid-19 do not show any symptoms for the first days after they are infected, masks clearly have a potential role to play, especially on crowded public transport as people return to work..
Sarah Boseley Health editor
Mainland China has reported more than 84,000 cases and more than 4,600 deaths during the pandemic.
Fearful of another outbreak and a return to the draconian lockdowns, the authorities are drawing up plans for “10 days of battle”, directing each district of Wuhan to develop and submit plans to test all their citizens.
There are few details for the ambitious undertaking, but Chinese media has suggested the “10-day” directive is a time limit for each region, on staggered start times.
“Each district shall make arrangements for nucleic acid screening for all members within 10 days,” said a Wuhan government notice.
On Tuesday, Yicai news said Wuchang district was to be screened between 13 and 20 May, with the intention of finishing by 17 May to allow three days “to find out and fill in the gaps”.
Caixin Global reported some districts would start this week and some next. The article cited Wuhan disease control officials saying the testing would be done by third-party companies and some hospital and disease control employees.
However, it said the rate of testing was limited to a maximum of 100,000 a day. China has not publicly said what its national testing capacity is, but it is believed to be far more than the US average of 300,000.
A resident of Jianghan, once the worst-hit district of Wuhan, told media he received a registration form on Tuesday instructing him and his family to either report having been tested or register for testing.
Peng Zhiyong, the director of the intensive care unit at the Wuhan University’s Zhongnan hospital, told the Global Times that he had not received any details of the testing plan as of Tuesday.
Peng said testing everyone would be expensive, and he believed it would focus on key groups and communities, such as vulnerable groups, medical staff and close contacts of people with the virus and their family members.
The reported cases are confined to one residential compound, where one 89-year-old man is ill with Covid-19 and five others have tested positive but are asymptomatic. According to the BBC, the housing manager of the complex was removed from his role.
Wuhan’s new outbreak drew concern on Chinese social media. “We still need to take protective measures; five cases is really terrible,” wrote one Weibo user.
“It’s not easy to slow down,” wrote another. “I felt a little relaxed and now it starts again, and I’m starting to panic again. Come on, Wuhan.”
The country’s reported numbers show a massive decline in infection rates, but small outbreaks are drawing swift and strict responses. The north-east of China, near the borders with Russia and North Korea, are emerging as a possible hotspot.
Chinese nationals returning from Russia were identified as carrying the disease into Heilonjiang province last month. This week, Jilin city and Shulan were placed under various lockdown measures after more than a dozen cases were confirmed.
Additional reporting by Lillian Yang
