A New Report Examines First Reported Spread of Vaccinia Virus Through Shaving After Contact Transmission

On June 9, the patient sought medical care at the trainee clinic at the Joint Base San Antonio–Lackland, Texas, and complained of “bumps on his face” after noticing a single small lesion on the underside of his chin three days earlier, according to the report published in the August issue of Medical Surveillance Monthly Report (MSMR) from the Armed Forces Health Surveillance Center (AFHSC) released on August 27. He described the site of the initial lesion as itchy and burning until it “popped” later that day. Within two days, he noticed more lesions on the chin, lower jaw and throat. He had shaved his face and neck on the day of and the day following the rupture of the initial lesion.

Over the past decade, most cases of contact vaccinia (i.e., spread of the virus from a vaccinated person to an unvaccinated person) have been traced to U.S. service members, who comprise the largest segment of the population vaccinated against smallpox. Most involve women or children who live in the same household and/or share a bed with a vaccinee or with a vaccinee’s contact. Of adult female cases, most are described as spouses or intimate partners of vaccinees or secondary contacts. Of adult male cases, most involve some type of recreational activity with physical contact, such as wrestling, grappling, sparring, football, or basketball. Household interactions (e.g., sharing towels or clothing) and “unspecified contact” are also implicated.

“The numbers of reported cases of spread of the vaccine virus to other, unvaccinated persons have fallen off sharply since the first few years after the Department of Defense resumed smallpox vaccination in 2002, but they still happen,” Navy Captain Kevin Russell, director of the AFHSC. “The cases in this article illustrate some of the reasons that the vaccine virus can be spread to others.”

The patient was admitted to the hospital from the dermatology clinic because of concerns about facial vaccinia. On the day of admission, four days after lesion onset, the patient developed a fever of 39.3°C (102.7°F). The U.S. Centers for Disease Control and Prevention (CDC) was contacted to request the release of intravenous vaccinia immune globulin (VIG) for possible treatment in accordance with the “aberrant infection” indication for VIG use, the report said. Further consultation was obtained from the Armed Forces Immunization Healthcare Center (AFIHC; formerly the Military Vaccine Agency–Vaccine Healthcare Centers Network).

Per AFIHC guidance, four facial lesions were sampled by removing the scabs and swabbing the moist lesions underneath. Within several hours of shipping the swabs to the local Laboratory Response Network laboratory, vaccine virus was isolated from the four submitted samples. Through a coordinated effort between the CDC and the U.S. Army Medical Materiel Agency, sufficient VIG was obtained and shipped.

VIG arrived the evening of the patient’s third day in the hospital. After the patient’s level of serum immunoglobulin A was confirmed to be normal, he received an intravenous administration of 6,000 units per kilogram of VIG for a total dose of 372,000 units.

On the fourth day in the hospital, the patient was afebrile and had a notable decrease in his facial swelling, erythema, and pain. Thereafter, the lesions progressed as expected: crusting, scabbing, and separation of the scabs (Figure 1c). The patient was discharged when all scabs had separated, 27 days after rash onset and 23 days after initial admission. Apart from some scarring (Figure 1d), he suffered no additional sequelae.

After the patient’s diagnosis of contact facial vaccinia, the installation’s public health department conducted an epidemiologic investigation. Of the 87 students on the patient’s security forces training squadron, 13 had received smallpox vaccinations on May 20. Combatives training had occurred during June 2–6, placing the vaccinated members at approximately day 13 of the smallpox vaccine “take” time frame at the start of combatives training.

Public health and preventive medicine officials initiated an investigation to inspect potential sites of exposure—including the smallpox vaccine clinic and the security forces facilities—and to determine the extent of the outbreak.

Vaccinia inoculation sites are typically covered with a Tegaderm™ dressing. However, for the 26 recipients vaccinated from May 20 through June 6, Band-Aids® were used instead of Tegaderm as dressings. Band-Aids are acceptable covers of smallpox vaccination sites; however, in this case, only larger bandages were recommended given the physical contact involved in certain training exercises.

Public health facility inspectors evaluated the squadron dormitory and combative laboratory. No discrepancies were noted in the dormitory. The combative facility was generally clean, and shared training equipment (e.g., helmets, handcuffs, flak vests, and mock weapons) was being regularly sanitized.

The inspection revealed that floor mats, although cleaned, were not regularly sanitized. It was recommended that an antimicrobial agent capable of killing vaccinia virus should be used, such as standard hospital-grade disinfectants with quaternary-ammonia compounds or a hypochlorite solution (ideally 10 percent household bleach). Mats are now sanitized at the end of each training day. Preventive medicine officials also advised the security forces commanders to reschedule combative training to precede smallpox vaccination.

The team members of the index case were instructed to report to the trainee clinic if they had any skin lesions or otherwise felt ill. On June 11, eight students were evaluated in the clinic; of these, three were returned to training and five were referred to dermatology clinic for further evaluation. Dermatology clinic staff diagnosed one student with a non-viral reaction and the others with either acne vulgaris or folliculitis. The roommate of the initial patient was also referred for dermatologic evaluation; he was cleared of current infection by history and physical examination and advised not to use any of his roommates’ personal hygiene products.

On June 13, an unvaccinated student on another team in the security forces squadron reported to the clinic with four crusted papules of the left upper arm (Figure 2). The first papule appeared five days after he had received a tattoo at the same location. He noted that his roommate, who had been vaccinated against smallpox three weeks prior, was not keeping his vaccination site covered at all times and had mistakenly used the patient’s towel.

Another one of the students identified during active case finding presented to clinic on June 11 June with multiple 2- to 4-millimeter skin-colored to pink papules on the dorsal aspect of his hands and extensor surfaces of his upper arms (Figure 3). He had received the smallpox vaccination 24 days prior, and clinic providers were concerned about possible extensive autoinoculation. He was referred to the dermatology clinic where a non-viral reaction to the vaccination was diagnosed.

“The investigation described in this article and the discussions of the preventive measures that are necessary to prevent spread of the vaccine virus serve as a thorough refresher for commanders and public health officials on how to minimize the risks associated with the vaccination program,” Captain Russell said.”

Click here to read entire study. The MSMR is the flagship publication for the AFHSC, featuring articles on evidence-based estimates of the incidence, distribution, impact and trends of illness in members and associated populations.