The BBC looks at the joint WHO-China report on the origins of Covid-19, saying a lack of access to blood samples from donors in the city and swab samples from adults, stands out. As does the lack of access to samples of frozen food, from domestic suppliers, sold at Huanan wholesale market – the place where a significant cluster of the first cases emerged.
In the now infamous Huanan market, Covid-19 traces were found on numerous surfaces. But there was no evidence of the disease in animal products collected from the stalls in early January 2020. Nor from suppliers.
China has repeatedly emphasised the possibility of contamination – even origin – through cold chain supply. Just over 1,000 samples of imported frozen foreign goods on sale at the time, which were still in stock, were tested. All were negative. The report says no domestic supplies were available.