title: Different routes and doses influence protection in pigs immunised with the naturally attenuated African swine fever virus isolate OURT88/3.
abstract: This study compares different combinations of doses and routes of immunisation of pigs with low virulent African swine fever virus (ASFV) genotype I isolate OURT88/3, including the intramuscular and intranasal route, the latter not previously tested. Intranasal immunisations with low and moderate doses (103and 104TCID50) of OURT88/3 provided complete protection (100%) against challenge with virulent genotype I OURT88/1 isolate. Only mild and transient clinical reactions were observed in protected pigs. Transient moderate virus genome levels were detected in blood samples after challenge that decreased, but persisted until the end of the experiment in some animals. In contrast, pigs immunised intramuscularly with low and moderate doses (103and 104TCID50) displayed lower percentages of protection (50-66%), and low or undetectable levels of virus genome were detected in blood samples throughout the study. In addition, clinical courses observed in protected pigs were asymptomatic. In pigs that were not protected and developed acute ASF, an exacerbated increase of IL-10 sometimes accompanied by an increase of IFNγ was observed before euthanasia. These results showed that factors including delivery route and dose determine the outcome of immunisation with the naturally attenuated isolate OURT88/3.
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom. Electronic address: pedro.sanchez-cordon@pirbright.ac.uk.
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: Sánchez-Cordón
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Dave
authors.initials: D
authors.lastname: Chapman
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Tamara
authors.initials: T
authors.lastname: Jabbar
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Ana L
authors.initials: AL
authors.lastname: Reis
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Lynnette
authors.initials: L
authors.lastname: Goatley
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Netherton
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Geraldine
authors.initials: G
authors.lastname: Taylor
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Maria
authors.initials: M
authors.lastname: Montoya
authors.affiliation: The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey, United Kingdom.
authors.forename: Linda
authors.initials: L
authors.lastname: Dixon
mesh_terms: D000281:Administration, Intranasal; D000357:African Swine Fever / Q000517:prevention & control* / Q000821:virology; D000358:African Swine Fever Virus / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification / Q000472:pathogenicity; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D004279:DNA, Viral / Q000097:blood; D016679:Genome, Viral; D007273:Injections, Intramuscular; D007371:Interferon-gamma / Q000235:genetics; D016753:Interleukin-10 / Q000235:genetics; D013552:Swine; D014611:Vaccination / Q000379:methods / Q000662:veterinary*; D014613:Vaccines, Attenuated / Q000008:administration & dosage; D019562:Viral Load; D014765:Viral Vaccines / Q000008:administration & dosage*
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D014613:Vaccines, Attenuated; D014765:Viral Vaccines; D016753:Interleukin-10; D007371:Interferon-gamma
keywords: African swine fever; Cytokines; Immunisation routes; Pigs; Protection