title: Suitability of faeces and tissue samples as a basis for non-invasive sampling for African swine fever in wild boar.
abstract: A challenging aspect of ASFV control in wild boar populations is the design and implementation of effective surveillance and monitoring programmes, both for early warning, and to determine the ongoing epidemiological situation in an infected population. Testing blood samples requires invasive sampling strategies like hunting or capture of wild boar. Besides being biased towards healthy animals, such strategies are also linked to further spread of the virus. Non-invasive sampling strategies would increase the reliability of surveillance of ASFV in wild boar populations, without the negative side effects. This study evaluates the potential of faeces and tissue samples as a basis for non-invasive sampling strategies for ASFV in wild boar. In the acute phase (0-21 days after infection), in comparison with virus detection in blood, virus can be detected in faeces 50-80% of the time. This percentage decreases to below 10% for the subacute/chronic phase. ASFV DNA is quite stable in faeces. Half-lives range from more than 2 years at temperature up to 12°C, to roughly 15 days at temperatures of 30°C. In tissue samples, stored at 20°C, half-lives mostly range from 1.7 to 7.4 days. The sample of preference is the spleen, where the highest titres and highest half-life of ASFV DNA are observed. The level and duration of excretion of ASFV in the faeces, combined with the stability of the DNA, suggest that sampling of faeces could be the basis for a non-invasive sampling strategy to monitor ASFV in wild boar.
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR (CVI), Virology Department, P.O. Box 65, 8200 AB Lelystad, The Netherlands; University Utrecht, Faculty of Veterinary Medicine, Farm Animal Department, Yalelaan 7-9, 3584 CL Utrecht, The Netherlands. Electronic address: helena.ferreira@ARS.USDA.GOV.
authors.forename: H C
authors.initials: HC
authors.lastname: de Carvalho Ferreira
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR (CVI), Virology Department, P.O. Box 65, 8200 AB Lelystad, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Weesendorp
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR (CVI), Virology Department, P.O. Box 65, 8200 AB Lelystad, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Quak
authors.affiliation: University Utrecht, Faculty of Veterinary Medicine, Farm Animal Department, Yalelaan 7-9, 3584 CL Utrecht, The Netherlands.
authors.forename: J A
authors.initials: JA
authors.lastname: Stegeman
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR (CVI), Virology Department, P.O. Box 65, 8200 AB Lelystad, The Netherlands. Electronic address: willie.loeffen@wur.nl.
authors.forename: W L A
authors.initials: WL
authors.lastname: Loeffen
mesh_terms: D000357:African Swine Fever / Q000175:diagnosis* / Q000821:virology; D000358:African Swine Fever Virus / Q000235:genetics; D000818:Animals; D001826:Body Fluids; D005243:Feces / Q000821:virology*; D015203:Reproducibility of Results; D013048:Specimen Handling; D034421:Sus scrofa / Q000821:virology*; D013552:Swine
keywords: African swine fever virus; Faeces; Monitoring; PCR; Tissues