March 31, 2020 Coronavirus may remain, at least in some cases, in the saliva and feces of healed patients, even when the swab for diagnosis is negative. This was revealed by research published in the Annals of Internal Medicine and conducted at Beijing Ditan Hospital, Capital Medical University. This type of study has important practical implications, because it could lead to more lasting isolation measures even when the swab (pharyngeal) performed on a patient has become negative. Experts analyzed saliva and stool samples from 133 patients admitted to the Chinese hospital for the presence of the virus, even after the patients tested negative for the diagnostic swab. For 22 of the patients involved the examination of feces and saliva was positive (virus present) even after 39 and 13 days respectively from the negative swab. The study will have to be repeated on a larger sample of patients and above all it will be necessary to investigate whether those recovered with viruses that persist in stool and saliva are still contagious.