The closest I could find in online archives to a December 2019 pandemic discussion on 4chan was this single (terribly racist and cruel) comment from December 30th[0], "Don't worry. The worlds going to suffer a global pandemic soon (very, very, soon) which will wipe out poor urban populations..."

[0] https://archive.4plebs.org/pol/thread/237746333/#q237746818 (Warning, this link contains graphic hate speech like much of 4chan does and is not suitable for human consumption.)