At a press conference Tuesday, World Health Organization spokesman Christian Lindmeier called for testing of COVID-19 on samples from patients with unspecified pneumonia cases between November and December last year.

This is after Yves Cohen, the director of the intensive care unit at two hospitals in Paris, and his team tested 14 frozen samples from patients who had been suffering from flu-like symptoms over the past year and one of them tested positive.

The patient, who arrived at the emergency room on Dec. 27 and was released on Dec. 29 after showing improvement, indicates that the virus was already circulating outside China much earlier than official reports would suggest.

To this extent, Lindmeier insisted that testing these types of samples allows for a deeper understanding of the pandemic because "it's the old story of the deeper you look, the more you find."

More cases like the one reported by Cohen are likely to come to light in the coming weeks, helping to reconstruct the timeline that led to the current circumstances.