Respiratory infections can be transmitted through droplets of different sizes: when the droplet particles are >5-10 μm in diameter they are referred to as respiratory droplets, and when then are <5μm in diameter, they are referred to as droplet nuclei. According to current evidence, COVID-19 virus is primarily transmitted between people through respiratory droplets and contact routes. In an analysis of 75,465 COVID-19 cases in China, airborne transmission was not reported.
Links:
[1] http://admin.indiaenvironmentportal.org.in/reports-documents/modes-transmission-virus-causing-covid-19-implications-ipc-precaution
[2] http://www.indiaenvironmentportal.org.in/files/file/WHO-2019-nCoV-Sci_Brief-Transmission_modes-2020.2-eng.pdf
[3] http://admin.indiaenvironmentportal.org.in/category/publisher/who
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/global
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/coronavirus
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/respiratory-diseases
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-care