Fauci said that he was open to the coronavirus lab leak theory all along, saying acknowledged COVID-19 "could possibly be an engineered virus" with the potential of an accidental leak from a lab but maintains that the most likely origin was through zoonotic transmission, reported Fox News.      

Amid criticism of an inconclusive international probe into the virus' origins and new reports of Covid-related illness in the region weeks before it was officially identified, the theory is once again sparking debate that the virus leaked from Wuhan lab.        

Earlier this month, a report by Wall Street Journal had stated that three researchers from China's Wuhan Institute of Virology sought hospital care after they fell ill in November 2019, a month before Beijing reported the first patient with COVID-like symptoms.   

Fauci discussed a conference call that took place on February 1, 2020, just days after the World Health Organization raised the alert level on COVID-19, calling it a public health emergency of international concern, during an interview with USA Today this week.   

Fauci told USA Today that they decided on the call the situation really needed to be looked into carefully.                               

The call included several scientists, including Kristian Andersen, an expert in infectious disease at Scripps Research Translational Institute in California.     

In an email to Fauci the day before the call, and reviewed by Fox News, Andersen wrote that the unusual features of the virus make up a really small part of the genome so one has to look really closely at all the sequences to see that some of the features potentially look engineered.