Covid-19 was circulating in Italy in late November 2019, three months before the first local transmission was detected, a new study has shown.

Analysis was carried out on a swab taken from a 4-year-old child, who had respiratory problems and was vomiting, on 30 November 2019. He developed a rash the next day and the illness was mistaken for measles.

The swab, observed months later, showed that the child had been suffering from coronavirus, according to the study researchers at the University of Milan and published by the Centers for Disease Control and Prevention.

Researchers analysed oropharyngeal swab specimens collected between September 2019 and February 2020 from 39 people and one tested positive for Covid-19.