Randomized trial comparing vaccinia on the external surfaces of 3 conventional bandages applied to smallpox vaccination sites in primary vaccinees

Background. Concern about accidental contact transmission after smallpox vaccination has prompted various recommendations regarding vaccination site coverage. Methods. On days 6-8 after their first-ever smallpox vaccination, 63 adult subjects were randomized to apply a self-adhesive bandage (n = 20), gauze with adhesive tape (n = 21), or gauze with a semipermeable dressing (n = 22) over the vaccination site for a mean of 8 ± 2 h. Swabs from the external bandage surfaces and the vaccination sites were then assessed by real time vaccinia-specific polymerase chain reaction (PCR) in blinded fashion. Results. Among 58 subjects completing the study, PCR results were positive for the vaccination site in 55 (94.8%) and on 10 swabs (17.2%) from external bandage surfaces. There were no differences among the 3 bandages (P = .57). Conclusions. At 7 days after smallpox vaccination, a peak time for vaccinia shedding, a self-adhesive bandage was as effective as 2 bulkier, less convenient bandages in limiting PCR-detectable virus on the external surface.