Human Ocular Onchocerca lupi Infection Diagnosed in Norway

Document Type : Case Report


1 Department of Ophthalmology, Oslo University Hospital, Oslo, Norway

2 Department of Ophtalmology, Drammen Sykehus, Vestre Viken HF, Drammen, Norway

3 Department of Infectious Diseases, University Hospital of North Norway, Tromsø, Norway

4 Regional Advisory Unit for Imported and Tropical Diseases, Department of Infectious Diseases, Ullevål, Oslo University Hospital, Oslo, Norway



Introduction: Zoonotic Onchocerca lupi infection is a rare but emerging zoonotic disease affecting the eye, subcutaneous tissue and subdural cervical spine. Endemic areas of O. lupi are East and Central Europe, Turkey, Iran and the Northwest of the USA. Thirteen confirmed cases have been published in the world literature.
Case Presentation: We present a case of subconjunctival O. lupi infection in the left eye of a Norwegian male. The infection was most likely imported from Turkey. The diagnosis was verified by direct microscopy and molecular analyses with polymerase chain reaction (PCR) with subsequent sequencing. The worm did not contain microfilaria and was surgically removed. The patient was treated with tapering doses of topical steroids. At 6 months follow-up, he was asymptomatic.
Conclusion: Increasing numbers of O. lupi infections are reported and it is not clear whether the increasing number of infections is true or due to availability of novel diagnostic tools that correctly identify the cases. Humans cannot eliminate their exposure to vector-borne zoonotic diseases and increasing globalization increases the risk of infection. Both physicians and laboratory staff should be aware of the existence of zoonotic onchocerciasis in their countries.