China first informed the WHO (World Health Organization) of the existence of a new virus, soon to be named SARS-CoV-2, in late December, 2019. According to the WHO, the first laboratory-confirmed case of the new virus beyond China's borders was in January 13, 2020, confirmed by the Thailand Ministry of Public Health. However, a new study published in late August of this year reveals that the novel coronavirus was already circulating beyond China as early as September 2019.
The researchers leading this study were investigating measles and rubella when they came across cases of illness and rash that were found not to be caused by these two diseases. They decided to test the samples and twelve of them, from dates prior to when a pandemic was first declared, were found to be positive for SARS-CoV-2.
The cases were all from Italy, but although later transmission from China to Italy was confirmed, none of the cases in this study had any relevant travel history that would have explained their contracting a virus that is commonly believed to have originated in Wuhan, China.
Furthermore, four of the twelve people whose samples tested positive for SARS-CoV-2 had antibodies to the virus, with the earliest sample being that of an eight-month-old infant who was tested on 12 September 2019.
The researchers noted that the genetic sequences of the samples indicated that they derived from the original, Wuhan strain, suggesting that the virus was in circulation around the globe many months earlier than is widely believed.