“If he got the original wuhan 18 months ago, maybe he didn’t have good antibody reaction or maybe his antibodies lost their ‘go’ after 18 months?”
That’s what I’m betting. And he’s not vaccinated that’s for sure. He’s having a tough time getting his body to spin up antibodies to the 2020 infection. And if it’s mutated, Delta variant, etc. there may be a significant lag in anti-body production.
I got it in Jan ‘20 and have the J&J and 1st shot of Pfizer. Even with all that I had to take a day off work last week due to fatigue (my Covid-infection Proximity Alarm). A co-worker went out with Covid. But I tested negative last week.
The vaccines and prior encounters both work imo.
“And he’s not vaccinated that’s for sure.”
Absolute speculation.
Except you don’t know that. For sure.