The COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, is believed to have originated in late 2019 in the city of Wuhan, China. According to the World Health Organization (WHO) and various scientific studies, the virus likely jumped from animals to humans at a seafood market in Wuhan. The first known case was reported on December 1, 2019, and the outbreak rapidly escalated into a global pandemic.

The exact timing of the initial infection is challenging to pinpoint due to the nature of viral transmission and the early stages of the outbreak. However, genetic sequencing of the virus has provided insights into its origins. Studies have shown that the earliest cases in Wuhan were linked to the Huanan Seafood Wholesale Market, where live animals were sold. The virus is thought to have been transmitted from animals to humans, possibly through an intermediate host, although this has not been conclusively proven.

Data from the Chinese Center for Disease Control and Prevention (China CDC) and the WHO support the timeline of the outbreak. The first cluster of cases was identified in early December 2019, and the virus quickly spread within the city and beyond. By the end of December, the WHO was informed about the outbreak, and by January 2020, the virus had spread to other countries, marking the beginning of the global pandemic.

The rapid spread of the virus was facilitated by international travel, with cases being detected in various countries within a few weeks of the initial outbreak. The early lack of awareness and understanding of the virus's transmissibility and severity contributed to its rapid global spread.

In conclusion, the COVID-19 pandemic is believed to have originated in Wuhan, China, in late 2019, with the first known case reported on December 1, 2019. The virus likely jumped from animals to humans at a seafood market, and its rapid spread was due to the nature of viral transmission and international travel.