How SARS-CoV-2 causing COVID-19 is transmitted in humans?

So far three mechanisms of transmission have been identified:

1. Droplet, produced during coughing or sneezing.
2. Fomit transmission (e.g. surfaces infected with viral particles).
3. Fecal-Oral; A number of studies suggest that the viral particles could be found in human stool and the lack of proper hygiene may lead to new infections.