China has sent over 20,000 rural residents living in the epicentre of the country's latest virus outbreak to state-run quarantine facilities, as Beijing on Friday reported the worst nationwide figures since March.

The country had largely brought the virus under control after strict measures including mass testing and travel restrictions, but recent weeks have seen numbers climbing again, especially in the north, prompting a fresh wave of lockdowns.

Another 144 infections were reported by the National Health Commission on Friday -- the highest single-day tally since March last year -- mostly in Hebei province where more than 22 million people are in lockdown.

The surge appears to be fuelled by so-called "silent infections" -– or asymptomatic cases -– in mostly rural areas on the outskirts of cities.

Over 20,000 residents from villages around Shijiazhuang -- about 294 kilometres (180 miles) southwest of Beijing -- have been sent to state-run quarantine facilities starting from Wednesday, state broadcaster CCTV said.

The villagers are being housed in hotels, according to CCTV, with family members separated into different rooms.

"It's natural that they feel anxious and panic," Liu Jinpei, a psychologist at the centre, told CCTV, adding that authorities had set up a mental health hotline.

Officials are also rushing to build a massive new "centralised medical observation centre" in the area with over 3,000 makeshift beds to isolate those at risk of contracting the virus.

The state-run Global Times warned that the high number of cases in rural areas "sounds an alarm regarding loopholes in epidemic control" as many residents in villages are elderly.

Migrant workers are expected to return to villages for the national Lunar New Year holiday next month, potentially spreading the virus further.

China reported its first Covid-19 death in eight months on Thursday, as experts from the World Health Organization landed in Wuhan -- where the disease first emerged in late 2019 -- to investigate its origins.