title: An outbreak of bovine meningoencephalomyelitis with identification of Halicephalobus gingivalis.
abstract: Halicephalobus gingivalis is an opportunistic parasite which is known to cause fatal meningoencephalomyelitis primarily in equines but sporadically also in humans. In April 2014, laboratory examination of the head of a young dairy calf, euthanized due to severe central nervous system symptoms, revealed the presence of granulomatous to necrotizing encephalitis and myriads of nematodes in the brain lesion. Morphologically the parasites were identified as H. gingivalis. The diagnosis was confirmed by molecular analysis of the large subunit (LSU) rRNA and the small subunit (SSU) rRNA genes, revealing genetic variations of 0.5-4.4% and 0.7-8.6%, respectively, between the H. gingivalis isolated from the Danish calf and published isolates, collected worldwide from free-living and parasitic stages of the nematode. Clinical symptoms and histological changes indicated infection with H. gingivalis from another three calves in the herd. This is the first scientific publication of H. gingivalis induced meningoencephalomyelitis in ruminants. As ante mortem diagnosis is a major challenge, the infection may easily remain undiagnosed in cattle.
authors.affiliation: National Veterinary Institute, Technical University of Denmark, DK-1870 Frederiksberg C, Denmark; Norwegian Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway. Electronic address: heidi.enemark@vetinst.no.
authors.forename: Heidi Larsen
authors.initials: HL
authors.lastname: Enemark
authors.affiliation: National Veterinary Institute, Technical University of Denmark, DK-1870 Frederiksberg C, Denmark.
authors.forename: Mette Sif
authors.initials: MS
authors.lastname: Hansen
authors.affiliation: National Veterinary Institute, Technical University of Denmark, DK-1870 Frederiksberg C, Denmark.
authors.forename: Tim Kåre
authors.initials: TK
authors.lastname: Jensen
authors.affiliation: National Veterinary Institute, Technical University of Denmark, DK-1870 Frederiksberg C, Denmark.
authors.forename: Gitte
authors.initials: G
authors.lastname: Larsen
authors.affiliation: National Veterinary Institute, Technical University of Denmark, DK-1870 Frederiksberg C, Denmark.
authors.forename: Mohammad Nafi Solaiman
authors.initials: MN
authors.lastname: Al-Sabi
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis / Q000469:parasitology* / Q000473:pathology; D004196:Disease Outbreaks / Q000662:veterinary*; D004679:Encephalomyelitis / Q000175:diagnosis / Q000469:parasitology / Q000473:pathology / Q000662:veterinary*; D020459:Genes, rRNA / Q000235:genetics; D010802:Phylogeny; D017168:Rhabditida / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D017196:Rhabditida Infections / Q000175:diagnosis / Q000469:parasitology / Q000473:pathology / Q000662:veterinary*
keywords: CNS; Calf; Halicephalobus gingivalis; LSU rRNA; Meningoencephalomyelitis; SSU rRNA