So, while Airbnb has been raising service fees, canceling reservations and issuing vouchers in an attempt make up for lost revenues, it appears that some other short-term rental related businesses have been working on their side-hustle, and are now offering online courses and issuing cleaning "certifications": www.cleaningcertification.com.
The course material is only a compilation of information that is available to the general public from the WHO, CDC, Mayo Clinic, etc. For $20USD and 30 minutes of your time, you can get a decal badge, similar to the Superhost badge, to display on your listing.
The course providers are spreading the word via affiliates to endorse and market their offerings in exchange for a 10% commission. I am sure that eventually the larger OTAs such as Booking.com, Expedia.com, Hotels.com, and probably Airbnb will buy-in after they are able to negotiate a higher commission. Then, they too will promote this cleaning certification, or another one, to hosts and guests.