The 25-year-old woman was affected by an atypical dermatitis and a biopsy on her skin cells, conducted on November 10, 2019, detected the presence of the novel coronavirus, according to the study, published on Thursday by the British Journal of Dermatology.
At the time the woman reported having a mild sore throat; months later, she tested positive for COVID-19 antibodies in her blood.
The virus can cause skin disorders including rashes and discolouration of fingers or toes, though they are less common than the “classic” symptoms (fever, tiredness and a dry cough).
“All these facts lead us to believe that our patient could represent the oldest case in literature of detection of the virus on tissue sample,” the study reads.
Previously, the first confirmed COVID-19 patient in Italy was a child in Milan, who was swabbed after developing a measles-like rash in early December 2019 – two months before it became clear that the virus was circulating in the nearby town of Codogno, where “native” cases were first detected in mid-February.
Researchers do not believe that the woman in the study was the first person in Italy to contract the new coronavirus, however.
“Probably, continuing to search, we would also find [the virus] in samples from October 2019,” Raffaele Gianotti, who led the study, told Italian news agency ANSA.
A separate study found traces of SARS-CoV-2 in samples of waste water in Milan and Turin from December 2019, though not from October or November.
Meanwhile, more than 100 people who enrolled in a lung cancer screening trial between September 2019 and March 2020 were discovered to have antibodies in their blood, indicating that they had already been exposed to the virus without noticing symptoms.
A handful of people had developed antibodies as early as the first week of September 2019, recent research found.
The first COVID-19 outbreak was reported in Wuhan, China, in December 2019 – although Chinese authorities have admitted that there were cases dating back to November, raising doubts over the transparency of the official data made public.