I'm wondering if it could be something contaminated inside a sterile container... something that would be delivered to hospitals and doctor's offices... something that would be made and/or delivered nearby IH95 from Chester PA to the elderly lady's doctor's offices or clinics in CT.
That particular trail of infections and suspected infections (and suspicious people) seem to have medical facilities in common. If I were the FBI, I'd be all over the doctor's office, his trash, etc.
Needles, bandages, lab kits, gloves, etc. are in sterile containers and once used are thrown away - thus minimizing the potential for additional contamination.