title: Invasion of the central nervous system in a porcine host by nipah virus.
abstract: Nipah virus, a newly emerged zoonotic paramyxovirus, infects a number of species. Human infections were linked to direct contact with pigs, specifically with their body fluids. Clinical signs in human cases indicated primarily involvement of the central nervous system, while in pigs the respiratory system was considered the primary virus target, with only rare involvement of the central nervous system. Eleven 5-week-old piglets were infected intranasally, orally, and ocularly with 2.5 x 10(5) PFU of Nipah virus per animal and euthanized between 3 and 8 days postinoculation. Nipah virus caused neurological signs in two out of eleven inoculated pigs. The rest of the pigs remained clinically healthy. Virus was detected in the respiratory system (turbinates, nasopharynx, trachea, bronchus, and lung in titers up to 10(5.3) PFU/g) and in the lymphoreticular system (endothelial cells of blood and lymphatic vessels, submandibular and bronchiolar lymph nodes, tonsil, and spleen with titers up to 10(6) PFU/g). Virus presence was confirmed in the nervous system of both sick and apparently healthy animals (cranial nerves, trigeminal ganglion, brain, and cerebrospinal fluid, with titers up to 10(7.7) PFU/g of tissue). Nipah virus distribution was confirmed by immunohistochemistry. The study presents novel findings indicating that Nipah virus invaded the central nervous system of the porcine host via cranial nerves as well as by crossing the blood-brain barrier after initial virus replication in the upper respiratory tract.
authors.affiliation: National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Canadian Science Centre for Human and Animal Health, 1015 Arlington St., Winnipeg, MB R3E 3M4, Canada. hweingartl@inspection.gc.ca
authors.forename: Hana
authors.initials: H
authors.lastname: Weingartl
authors.forename: Stefanie
authors.initials: S
authors.lastname: Czub
authors.forename: John
authors.initials: J
authors.lastname: Copps
authors.forename: Yohannes
authors.initials: Y
authors.lastname: Berhane
authors.forename: Deborah
authors.initials: D
authors.lastname: Middleton
authors.forename: Peter
authors.initials: P
authors.lastname: Marszal
authors.forename: Jason
authors.initials: J
authors.lastname: Gren
authors.forename: Greg
authors.initials: G
authors.lastname: Smith
authors.forename: Shelley
authors.initials: S
authors.lastname: Ganske
authors.forename: Lisa
authors.initials: L
authors.lastname: Manning
authors.forename: Markus
authors.initials: M
authors.lastname: Czub
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000821:virology; D001921:Brain / Q000821:virology; D002490:Central Nervous System / Q000821:virology; D020805:Central Nervous System Viral Diseases / Q000503:physiopathology / Q000662:veterinary* / Q000821:virology; D002555:Cerebrospinal Fluid / Q000821:virology; D003391:Cranial Nerves / Q000821:virology; D005260:Female; D006168:Guinea Pigs; D045464:Henipavirus Infections / Q000503:physiopathology* / Q000821:virology; D006801:Humans; D007150:Immunohistochemistry; D045405:Nipah Virus / Q000472:pathogenicity*; D013552:Swine; D013553:Swine Diseases / Q000503:physiopathology* / Q000821:virology*; D012668:Trigeminal Ganglion / Q000821:virology