中國-世界衛生組織聯合專家組中方組長梁萬年說，中國的研究人員已經對該國的蝙蝠進行了廣泛的調查和取樣，但沒有發現蝙蝠體內的病毒與新型冠狀病毒足够相似，可以認為是該病毒的來源。 “不同類型的蝙蝠廣泛分佈在全球各地，一些地區從未對它們進行過系統的研究，”他說，“科學家們一致認為，在探索病毒起源的過程中，蝙蝠應該是一個重點， 相關研究不應局限於中國，而應以更廣闊的視角覆蓋所有蝙蝠居住的國家和地區。”

義大利和荷蘭的兩個實驗室重新檢查了7月新冠疫情爆發前採集的血樣，發現新冠病毒感染者體內普遍存在抗體。 巴西聖卡塔裏納聯邦大學的專家組在去年7月發現2019年下水道樣本中存在新冠病毒-19。 一些血液樣本顯示，在武漢正式確定新冠病毒19之前，美國和法國的一些人可能已經感染。

據確定，在疫情爆發之前，有20個國家向武漢的華南海鮮市場進口了冷鏈產品，包括阿根廷、澳大利亞、巴西、加拿大、智利、法國、俄羅斯和美國。

Researchers in China have extensively surveyed and sampled bats in the country without identifying a virus in them that is similar enough to the novel coronavirus to be considered the virus' source, said Liang Wannian, the team leader of the Chinese side of the China-World Health Organization joint expert team."Bats of different types are widely dispersed around the globe, and some regions have never launched systematic research on them," he said. "As scientists agree that bats should be a focus during the probe into the virus' origin, relevant research should not be limited to China but take a wider perspective to cover all countries and regions inhabited by bats."

Two laboratories in Italy and Holland re examined blood samples collected before the outbreak of the new crown outbreak in July, and found antibodies commonly found in new crown virus infected individuals. The expert group of the Federal University of Santa Catarina in Brazil discovered in July last year that there were COVID-19 in the sewer samples in 2019. Some blood samples showed that some people in the United States and France might have been infected before Wuhan officially decided COVID-19.

It was determined that 20 countries imported cold chain products to the South China seafood market in Wuhan before the outbreak, including Argentina, Australia, Brazil, Canada, Chile, France, Russia and the United States.