Researches from Harvard University studying the strains of the recent outbreak of coronavirus in Beijing in June suggest that strains may have originated in South or South East Asia.
The study looked at the genetic sequencing data of three virus strains from patients in Beijing made public by the Chinese Centre for Disease Control and Prevention.
The sudden outbreak triggered speculations of a second wave in China, but officials quickly ramped up test. Until Sunday this week Beijing tested one third of its population, about 7.69 million people.
Beijing reported over 300 coronavirus cases in June taking the total number of infections to 919.
Georg Hahn, a research associate with the Biostatistics Department of the Harvard T.H. Chan School of Public Health, and his team compared these genes to more than 7,000 genome sequences reported from around the world.
They found the three strains were part of a group that has been mostly circulating in Europe, but has recently been reported “almost exclusively” in Asia’s tropical zone.
The new virus cases were circulated between May to June.
The outbreak traced to Beijing’s huge Xinfadi wholesale market on June 11 had infected 329 people by the end of Wednesday.
Quarantine restrictions and large-scale testing of residents began soon after the first cases were identified, and China also required all shipments of imported meat to be tested for COVID-19 before they could leave its ports.
The virus has claimed over 10.7 million cases globally with over 516,000 deaths.