Beijing, 19 August 2022 (dpa/MIA) — The Chinese authorities have begun testing fish caught at sea for SARS-CoV-2, prompting ridicule on social media in their efforts to contain a major outbreak. Videos of fish being swabbed in the port city of Xiamen have been widely shared online in China, triggering a range of reactions. "What do they do with a close contact? Quarantine the fish at sea?" one person wrote. "Off to a quarantine center if they're positive?" China's SARS-CoV-2 containment policies are the strictest in the world, with the authorities imposing repeated, lengthy lockdowns and mass testing. A representative of Xiamen's health department confirmed that the authorities were testing not only returning fishermen but also the fish they had caught. "What comes in has to be tested," the spokesperson told dpa on Friday. The step came after the Jimei district issued a directive last month highlighting a danger from illegal trade with foreign fishermen at sea and requiring people and goods to be tested when fishermen and their catch come ashore. While much of the world is seeking ways to live with SARS-CoV-2, China — where the airborne virus was first detected in December 2019 — still has strict zero-tolerance regulations in place. The few people who may enter the country usually have to undergo quarantine for seven days in a hotel then spend three days under observation. People have to be tested every three days in many of the country's sprawling urban areas. Citizens must prove they have tested negative for the virus through an app before they may enter shops, markets or even their own apartment complexes. Anyone who comes into contact with the virus has to isolate, while those who test positive are hospitalized. Where cases break out, entire neighborhoods are sealed off. Despite these measures, China is grappling with a major wave of cases, with the highly-transmissible Omicron variant spreading rapidly. China's health commission in Beijing reported more than 500 new cases and more than 2,000 asymptomatic cases on Friday, with many identified at a popular holiday resort island. The outbreak has left tens of thousands of holidaymakers stranded on the southern Chinese resort island of Hainan, after local authorities ordered a mass lockdown as the region had the country's highest number of SARS-CoV-2 infections earlier this month. The Xiamen Marine Development Bureau told Hong Kong-based newspaper South China Morning Post that the coronavirus may have been brought to Hainan by fishermen who may have come into contact with others from abroad at sea, according to reports. "We're not the only place doing this," the bureau was quoted as saying, referring to the practice of testing of fish and fishermen alike.