CD40LG and COVID-19: Other keywords included product descriptions that users could easily understand and identify including “immunity spray,” “Corona Kit,” and “IgM/IgG.” Because hashtags provide a way for users to curate topics of common interest, many posts included hashtags of the specific product they were selling (eg, #hydroxychloroquine, #IgM/IgG #test, and #testkit) in combination with general COVID-19 tags (eg, #coronavirus, #COVID9, and #rapidtest).