Re-testing of blood samples has shown that coronavirus may have been circulating in Italy as early as October 2019, two months before China alerted the world to the new disease, researchers have claimed.
The World Health Organization asked for further clarification from researchers at a cancer centre in Milan after they claimed last November that samples from cancer patients had antibodies, showing the virus may have been circulating for several months in northern Italy – even before the first cases were reported in China in November 2019.
“The results of this retesting suggest that what we previously reported in asymptomatic patients is a plausible signal of early circulation of the virus in Italy,” Giovanni Apolone, one of the researchers, told the Financial Times.
However, other experts said the findings needed to be interpreted with caution. Paul Hunter, professor in medicine at the University of East Anglia, said other coronaviruses circulating could have sparked an antibody response.
“This paper is insufficient to prove that the virus was circulating in October. That is not to exclude this as a possibility, just that the paper, though interesting, does not provide sufficient proof,” he said.