(Bloomberg) -- China reported 130 people over the past day who were infected with the novel coronavirus but don’t have symptoms, a sign that the group of people who can spread the virus without being detected is sizable.

The tally, the first daily count of so-called asymptomatic patients, establishes a new benchmark to measure the scope of the outbreak amid a growing chorus of domestic and international criticism of China’s data.

China late Tuesday said 1,541 asymptomatic people have been put under observation. Wednesday’s data confirms that figure was a cumulative total, though it isn’t clear if the number represented people currently in medical quarantine or if it included those who were symptom-free but have since recovered and been released.

The disclosures of asymptomatic infections come after Chinese Premier Li Keqiang urged local officials to prioritize efforts to track and expand the screening of symptom-free carriers.In China, people who test positive for the virus but don’t have any symptoms are not classified as confirmed cases. This runs counter to the practice in countries like South Korea, Japan and Singapore, where all patients who test positive are included in official tallies of total cases, regardless of whether they have symptoms such as a fever or cough.

China’s total count of confirmed Covid-19 infections stands at more than 81,000, but the vast majority have recovered and been released.

Cases of asymptomatic virus infections are still being found, local magazine Caixin reported, even after China said its daily confirmed case tally hit zero for the first time two weeks ago. That’s fueled doubt over whether the epidemic that broke out in the central Chinese city of Wuhan in December is truly over.

China says it tracks and quarantines asymptomatic cases and reclassifies them as confirmed cases if and when they develop symptoms. On Wednesday, it said that two such patients have been reclassified.

Concern over China’s earlier refusal to disclose the number of symptom-free carriers grew as researchers found these patients can play an outsized role in spreading the pathogen to others, since there’s no easy way to tell they’re sick.

While it’s unclear what proportion of infected people do not display symptoms, scientists suspect it could be a substantial number and that these stealthy carriers are still infectious -- a key reason why the pandemic has spread so widely across the world in a short time.

©2020 Bloomberg L.P.