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

Abstract

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.