A team of scientists from the World Health Organization, investigating the origin of the Covid-19 pandemic, has zeroed in on a 25-year-old woman in Milan who reportedly suffered from coronavirus symptoms, the media reported.

The Milan resident in November 2019 visited a hospital with a sore throat and skin lesions -- the symptoms of Covid -- a month before the virus was actually discovered in the city of Wuhan in China, the Wall Street Journal reported.

A research published by the British Journal of Dermatology, in January, revealed that the woman left behind a skin sample, smaller than a dime, that in two tests conducted more than six months later yielded traces of the SARS-CoV-2 virus that causes Covid-19.

Previous studies have shown that the deadly infectious virus likely began spreading unnoticed in China, before causing an outbreak a month later. The woman's case further asserts the theory, the scientists said, pressing the need for additional studies.

"The Covid-19-positive skin sample, sitting in wax in a researcher's office in Milan, is an example of the scattered clues about the pandemic's early days that the WHO-led investigation is pursuing outside of China, where the pandemic began," the WSJ report said.

"You cannot ignore it," Dutch virologist Marion Koopmans, a member of the WHO-led team, was quoted as saying, referring to the Italian case in an interview earlier.

According to Koopmans, the case offered enough evidence to merit broader investigation into whether the virus had spread to Italy by November 2019.

The problem, researchers say, is that the identity and whereabouts of the woman remain unknown, the report said.

The WHO has recommended searching for possible Covid-19 cases in other countries that predate the first confirmed Wuhan case. The finding may help draw a timeline of the early spread of the virus. For this, the team has also asked blood banks in several countries to test samples from late 2019 for the presence of coronavirus antibodies.

Globally, many experts have pushed to determine the origins of the pandemic. The debate is between its natural origin and the theory that Covid-19 leaked out of a Chinese laboratory.