you forgot option of US bioweapons lab
check this out
On July 9th, another pneumonia of unknown cause was reported in Alexandria, VA and all lung images showed the ‘ground glass’ shadow typical of Covid-19. Coincidentally, the CDC chose that date to withdraw the only American epidemiologist embedded with Beijing’s CCDC. The following week a pneumonia epidemic was reported at a nursing home in Burke, VA and the Virginia State Health Bureau banned collective activities and began screening residents in assisted care facilities and requiring enhanced hygiene. In early August the CDC expanded its pneumonia patient detection system and, in an unprecedented civilian intervention in military affairs, shut down the Army’s main military biowarfare lab (and Superfund site), Fort Detrick, MD where, a senior scientist said, the atmosphere was one of “fear and mistrust.”
https://www.unz.com/article/the-hunt-for-patient-zero/