I have checked and it all seems right to me. Hot spot was 93 but I bumped it to 94.5 when I saw sickness the first time. Humidity runs between 60-75% sometimes a bit higher due to weather here in FL. Ambient is between 80-85 F night-day. When I change the tubs I pull them out two at a time, one shelf at a time. They could have come in contact then and are right next to each other in the rack. He would be the most likely of any of them to have caught it from her. I checked all my others yesterday and they all seem fine also.