Age: 27.0
Sex: M
Vaccine: SMALL
Symptoms: Blood immunoglobulin G increased, Blood test, Cellulitis, Culture positive, Debridement
Clinical narrative: Initial unsolicited case received on 30 April 2015 from literature. A 27-year-old male patient, whose medical history and concomitant medications were not reported, received ACAM2000 (lot number not reported) on 28 January 2013. On 05 February 2013, nine days after vaccination the patient was evaluated and found 0.5 cm white lesion at the center of the vaccination site. Wound edges were pink but intact. Scant yellow/green drainage was present on the dressing. On follow-up a week later, a 0.5-cm brown dry eschar was present at the center of the wound. This was consistent with a major cutaneous reaction or take, "suggesting a successful response to vaccination". Approximately nine months later, on 17 November 2013, he was accidentally exposed to wild type vaccinia virus (VACV) Western Reserve in the left thumb after recapping a 25 gauge needle he was using to inoculate a mouse by scarification at the laboratory where he was working. The following is verbatim from the literature report: "On November 26, 2013, the CDC poxvirus laboratory was notified by the Public Health Commission (PHC) of an inadvertent inoculation of a recently vaccinated (ACAM2000 smallpox vaccine) laboratory worker with wild type vaccinia virus (VACV) Western Reserve. A joint investigation by CDC and PHC confirmed orthopoxvirus infection in the worker, who had reported a needle stick in his thumb while inoculating a mouse with VACV. He experienced a non-tender, red rash on his arm, diagnosed at a local emergency department as cellulitis. He subsequently developed a necrotic lesion on his thumb, diagnosed as VACV infection. Three weeks after the injury, the thumb lesion was surgically debrided and at 2 months post-injury, the skin lesion had resolved. The investigation confirmed that the infection was the first reported VACV infection in a laboratory worker vaccinated according to the Advisory Committee on Immunization Practices (ACIP) recommendations. The incident prompted the academic institution to outline biosafety measures for working with biologic agents, such as biosafety training of laboratory personnel, vaccination (if appropriate), and steps in incident reporting. Though vaccination has been shown to be an effective measure in protecting personnel in the laboratory setting, this case report underscores the importance of proper safety measures and incident reporting." Case Report: "On November 23, 2013, a man aged 27 years who was a laboratory worker at an academic institution went to a local emergency department with a non-tender, erythematous rash on the skin over his left biceps and extending to the antecubital fossa. He reported a needle stick in his left thumb had occurred on November 17 while he was inoculating a mouse by scarification with VACV. He had no fever, chills, or other systemic or neurologic symptoms. An ultrasound of his left thumb revealed a small collection of fluid at the puncture site. No culture was performed. Cellulitis was diagnosed in the patient, and he was admitted to the hospital and given Cefazolin intravenously, 1 g every 6 hours for 18 hours. He was discharged on November 24 with a prescription for cephalexin, 500 mg orally four times a day for 10 days. A dressing was placed over the wound, and he was instructed to change the dressing three times a day and dispose of the contents in a biohazard container provided by the hospital. He was also instructed to report the next day to the occupational health clinic at the institution where he worked. On November 25, the patient went to the institution's occupational health clinic with a necrotic lesion on the volar surface of the left thumb and erythema over the left biceps extending to the volar forearm. A necrotic VACV infection was diagnosed, and the patient was advised to continue cephalexin. As required by PHC research laboratory regulations, occupational health notified PHC, which notified the state Department of Public Health and CDC. PHC initiated an investigation and reinforced infection control measures, including instruction on keeping the wound covered and proper disposal of dressings. An evaluation on November 26 revealed that the necrotic lesion on the thumb persisted, but erythema of the arm was less pronounced. A blood specimen was sent to the CDC for serological and molecular testing. By November 27, the lesion appeared stable and the erythema had resolved. On December 10, 23 days after the injury, the lesion was surgically debrided and a specimen was submitted for diagnostic testing at State Laboratory Institute and CDC. Orthopoxvirus infection was confirmed at both laboratories using polymerase chain reaction. VACV was isolated using tissue culture at CDC. Serology completed by CDC revealed high levels of orthopoxvirus immunoglobulin G. By January 9, 2014, the skin lesion had resolved, and the patient was asymptomatic." According to the authors, "The ACIP recommends smallpox vaccination for laboratory personnel who directly handle cultures or animals contaminated or infected with non-highly attenuated VACV". Additionally, "The patient's elevated levels of immunoglobulin G indicate prior exposure by vaccination and infection. However, the level of antibody that protects against VACV infection is unknown and antibody level might not be indicative of protective, neutralizing antibodies against infectivity." The outcome was resolved. Documents held by sender: complete literature article.