First Swedish case of fatal equine parasitic encephalitis by Halicephalobus gingivalis.

The research paper investigates the first-ever case of a fatal equine parasitic infection caused by Halicephalobus gingivalis in Sweden, found in a 21-year-old Icelandic horse. With the presence of this infection in Sweden, the authors recommend including it as a potential diagnosis for acute neurological diseases in various mammals.

Case Background

• The patient was a 21-year-old Icelandic horse imported into Sweden. The horse began exhibiting severe neurological signs and was eventually euthanized due to the severity of its condition. The horse was subsequently examined post-mortem, where severe kidney lesions were discovered.

Process and Findings

• Detailed histopathological examination of the horse’s kidneys and brain revealed the presence of Halicephalobus gingivalis – a nematode parasite known to cause fatal opportunistic infections in mammals.
• This particular case study holds importance on multiple levels, primarily because no such parasite infection had ever been reported in Sweden prior to this incident.
• Furthermore, the researchers performed a phylogenetic analysis of the found parasite and determined that it belonged to Lineage 1.

Conclusion and Recommendations

• Considering the fatal potential of this parasite and its newly discovered presence in Sweden, the researchers have strongly advocated for its inclusion in the differential diagnoses in cases involving acute onset of neurological disease in various mammals, including horses and humans.
• Indeed, the nematode’s zoonotic potential makes this recommendation even more significant, reminding medical professionals to be vigilant in diagnosing not just well-known diseases but also rare and opportunistic infections.