A four-year-old Italian boy contracted COVID-19 in November 2019, suggesting the virus was circulating in the country far earlier than originally believed - a finding that could see the pandemic timeline rewritten.
The young boy, who had no recent travel history, came down with respiratory symptoms and a measles-like rash before being admitted to hospital on November 30, three months before Italy's first known case of COVID-19.
A throat swab taken to be tested for suspected measles came back negative, leaving doctors puzzled as to what illness the boy had.
According to a new report published by the Centres for Disease Control and Prevention, the boy's swab has been re-analysed, returning a positive COVID-19 result.
The sample was tested alongside 39 other swabs collected from patients who also had measles-like symptoms from September 2019 to February 2020.
The four-year-old Milan boy was the only swab to come back as COVID-19 positive showing a 100 percent match to reference sequence Wuhan-HU-1 as well as other SARS-CoV-2 strains.
Researchers say earlier strains may have been imported throughout Europe during late 2019, "manifesting with sporadic cases or small self-limiting clusters".
The finding, researchers say, may help in explaining the severity of Italy's first wave of the virus: "Long-term, unrecognised spread of SARS-CoV-2 in Northern Italy would help explain, at least in part, the devastating impact and rapid course of the first wave of COVID-19 in Lombardy."
COVID-19 was also found to be present in Milan's wastewater as early as mid-December 2019 at concentrations "comparable" to those found in swabs tested at later stages of the pandemic.
This evidence only further suggests the spread of the virus occurred prior to Italy's patient zero - a Codogno man infected in mid-February - and before Europe's patient zero, a 43-year-old from Paris who got sick in November.
Italy is among the countries hardest-hit by the pandemic, with over 1.7 million total cases and over 60,000 deaths to date.
