Social networking sites, by definition, are a place where personal interests and information are shared. Companies want this information so they can better target you with goods and services. Cyber criminals want this information so they can steal from you; or in the case of stalkers, possibly harm you.
Please do run full scan to confirm that your computer is safe. Please let us know what version of McAfee is installed on your computer.
Yes, first you need to run a full scan of your computer. If you use well-known social networks there is a small chance of getting a virus. Sometimes I use some chats or dating sites like https://www.tendermeets.com/ but always after that I check my computer for viruses.