Absence of pharyngeal shedding of vaccinia following smallpox vaccination

To examine oral shedding of vaccinia in volunteers who were recently vaccinated against smallpox, pharyngeal swabs were collected for viral culture between days 3 and 5 and days 6 and 8 after vaccination with diluted Sanofi Pasteur smallpox vaccine. From 102 adult volunteers (48 vaccinia-naive, 54 vaccinia-experienced), vaccinia was not detected in any specimen (0/201, 95% confidence interval, 0-1.8), which suggests a lack of oral shedding of vaccinia after immunization. This supports recommendations that individuals who were recently vaccinated against smallpox do not require placement in airborne or droplet precautions.