According to Bloomberg, SARS-CoV-2 infects a wide variety of human tissues along with the lungs, including the gut, and is frequently excreted by infected people.
Dutch researchers reported in March 2020 that they were able to find genetic material from the virus in wastewater before Covid-19 cases were reported in the population.
A mother had read about recent studies showing that COVID-fighting antibodies were present in breast milk and could possibly help her baby fight off the virus — though experts caution it’s unclear how much protection they actually get. She had received the vaccine but had to stop breastfeeding. By the end of the day, three women had offered her some of their supply.