Workers are being subjected to two tests: one that uses a specimen taken from their nose or throat to detect the coronavirus, and one that uses a blood sample to determine if they have Covid-19 antibodies. The latter could indicate the person had been infected with the coronavirus, recovered and developed some immunity, even if they were asymptomatic.
Demand for this kind of mass testing of workers started to increase in mid-March, when business in the city gradually resumed before the lockdown was fully lifted. Companies are already required by the local government to disinfect their factories daily and prepare sufficient protective supplies for their employees.
On top of that, state-owned enterprises, construction operators and other labor-intensive businesses have set up on-site testing centers run by private companies including UniMedLab, a gene testing institution.