Delayed diagnosis of parapoxvirus infections and a review of pox infections other than mpox in the United Kingdom

Abstract

Background

Orf virus is a member of the genus parapoxvirus. Orf is an infection of sheep and goats but humans can become infected after direct contact with an infected mammal. It is normally a self-limiting cutaneous infection but it has the potential to cause more severe infection in immunosuppressed individuals.

Case Report

We report two cases of delayed diagnosis of orf. The first case was a fifty-year-old sheep farmer who presented with a painful lesion on her finger. The second patient was a twenty-five-year-old veterinary nurse who presented with a painful lesion on her finger after being bitten by a lamb. Both cases were mis-diagnosed by a number of different clinicians and the second case received multiple courses of inappropriate anti-microbial therapy.

Results

Skin swabs from both cases were sent to the UKHSA Porton Rare and Imported Pathogens Laboratory (RIPL) for parapoxvirus PCR. Parapoxvirus DNA was detected in both cases, indicating presumptive orf infection.

Conclusion

A thorough history, including occupation and animal exposure, is key to making a prompt diagnosis of orf. Early recognition is required in order to prevent unnecessary anti-microbial therapy and surgical intervention, and to allow for prompt treatment in those severe cases where it is required.