Table 2. Article inclusion/exclusion criteria.

Inclusion criteria	Exclusion criteria
The review only focuses on COVID-19	Other viral infections and health issues were not considered relevant in the survey
Only articles that applied machine learning techniques to fight COVID-19 were considered	Articles using techniques other than machine learning techniques were excluded
Articles/conference papers published by prominent and indexed journals were included	Articles/conference papers published by non-indexed journals were excluded. The article uploaded as a preprint in preprint servers such as bioRxiv, medRxiv, arXiv, etc. without peer review were excluded
Only articles written in the English language were considered for inclusion	Articles written in languages other than English were excluded