Analyze Diet
Medical and veterinary entomology2007; 21(4); 377-383; doi: 10.1111/j.1365-2915.2007.00706.x

Virus recovery rates for wild-type and live-attenuated vaccine strains of African horse sickness virus serotype 7 in orally infected South African Culicoides species.

Abstract: Previously reported virus recovery rates from Culicoides (Avaritia) imicola Kieffer and Culicoides (Avaritia) bolitinos Meiswinkel (Diptera, Ceratopogonidae) orally infected with vaccine strain of African horse sickness virus serotype 7 (AHSV-7) were compared with results obtained from concurrently conducted oral infections with five recent AHSV-7 isolates from naturally infected horses from various localities in South Africa. Culicoides were fed sheep bloods spiked with 10(7.6) TCID(50)/mL of a live-attenuated vaccine strain AHSV-7, and with five field isolates in which virus titre in the bloodmeals ranged from 10(7.1) to 10(8.2) TCID(50)/mL). After an extrinsic incubation of 10 days at 23.5 degrees C, virus recovery rates were significantly higher in C. imicola (13.3%) and C. bolitinos (4.2%) infected with the live-attenuated virus than in midges infected with any of the field isolates. The virus recovery rates for the latter groups ranged from 0% to 9.5% for C. imicola and from 0% to 1.5% for C. bolitinos. The C. imicola population at Onderstepoort was significantly more susceptible to infection with AHSV-7 isolated at Onderstepoort than to the virus strains isolated from other localities. Results of this study suggest that tissue culture attenuation of AHSV-7 does not reduce its ability to orally infect competent Culicoides species and may even lead to enhanced replication in the vector. Furthermore, oral susceptibility in a midge population appears to vary for geographically distinct isolates of AHSV-7.
Publication Date: 2007-12-21 PubMed ID: 18092976DOI: 10.1111/j.1365-2915.2007.00706.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research examines the recovery rates of the African horse sickness virus serotype 7 from Culicoides species that were orally infected with different strains of the virus. The study finds higher virus recovery rates from Culicoides infected with live-attenuated vaccine strains of the virus than those infected with field isolates, and further suggests the role of genetic attenuation in the oral infectivity of the virus to Culicoides species.

Objective of the Study

  • The objective of the research is to compare the virus recovery rates of a live-attenuated vaccine strain and five field isolates of the African horse sickness virus serotype 7 (AHSV-7) in orally infected South African Culicoides species.

Methodology

  • The researchers orally infected Culicoides species with sheep blood containing the virus strain AHSV-7 and 5 field isolates, tracking virus numbers over time. The blood contained different titres of the virus, ranging from 10-7.1 to 10-8.2 TCID(50)/mL.
  • After an extrinsic incubation period of 10 days, the researchers determined the virus recovery rates

Findings

  • Higher virus recovery rates were observed in Culicoides infected with live-attenuated AHSV-7 virus (C. imicola – 13.3% and C. bolitinos – 4.2%) than those infected with any of the field isolates. The virus recovery rates in the latter groups ranged from 0% to 9.5% for C. imicola and from 0% to 1.5% for C. bolitinos.
  • The C. imicola population at Onderstepoort was significantly more susceptible to AHSV-7 isolated from the same location than to the strains of AHSV-7 that were isolated from other places.
  • Evidence from the study suggested that tissue culture attenuation of AHSV-7 doesn’t reduce its ability to orally infect competent Culicoides species. Instead, it may enhance the virus’ replication in the vector.
  • The research also suggested that oral susceptibility to AHSV-7 might vary in geographically distinct isolates amongst the midge species.

Implications

  • This study provides valuable insights about the influence of genetic attenuation on the oral infectivity of AHSV-7 to Culicoides species. It may have potential implications for the use of live-attenuated vaccines in controlling the spread of the virus.
  • The results highlight the need for understanding geographical variations in the susceptibility of Culicoides populations to different strains of AHSV-7, which can guide strategizing effective disease control measures.

Cite This Article

APA
Venter GJ, Paweska JT. (2007). Virus recovery rates for wild-type and live-attenuated vaccine strains of African horse sickness virus serotype 7 in orally infected South African Culicoides species. Med Vet Entomol, 21(4), 377-383. https://doi.org/10.1111/j.1365-2915.2007.00706.x

Publication

ISSN: 0269-283X
NlmUniqueID: 8708682
Country: England
Language: English
Volume: 21
Issue: 4
Pages: 377-383

Researcher Affiliations

Venter, G J
  • Department of Entomology, Agriculture Research Council-Onderstepoort Veterinary Institute, Onderstepoort, South Africa. venterg@arc.agric.za
Paweska, J T

    MeSH Terms

    • Administration, Oral
    • African Horse Sickness / prevention & control
    • African Horse Sickness / transmission
    • African Horse Sickness / virology
    • African Horse Sickness Virus / classification
    • African Horse Sickness Virus / isolation & purification
    • Animals
    • Ceratopogonidae / virology
    • Horses
    • Insect Vectors / virology
    • Serotyping
    • South Africa
    • Vaccines, Attenuated
    • Viral Vaccines / administration & dosage
    • Virus Replication

    Citations

    This article has been cited 11 times.
    1. Punyadarsaniya D, Taesuji M, Rattanamas K, Ruenphet S. Establishment of an In-House Indirect Enzyme-Linked Immunosorbent Assay to Detect Antibodies Against African Horse Sickness Based on Monovalent and Polyvalent Live Attenuated Vaccines During the First Outbreak in Thailand. Animals (Basel) 2025 May 15;15(10).
      doi: 10.3390/ani15101433pubmed: 40427310google scholar: lookup
    2. Li N, Meng J, He Y, Wang W, Wang J. Potential roles of Culicoides spp. (Culicoides imicola, Culicoides oxystoma) as biological vectors of bluetongue virus in Yuanyang of Yunnan, P. R. China. Front Cell Infect Microbiol 2023;13:1283216.
      doi: 10.3389/fcimb.2023.1283216pubmed: 38274733google scholar: lookup
    3. Kunanusont N, Taesuji M, Kulthonggate U, Rattanamas K, Mamom T, Thongsri K, Phannithi T, Ruenphet S. Longitudinal humoral immune response and maternal immunity in horses after a single live-attenuated vaccination against African horse sickness during the disease outbreak in Thailand. Vet World 2023 Aug;16(8):1690-1694.
    4. Taesuji M, Rattanamas K, Kulthonggate U, Mamom T, Ruenphet S. Sensitivity and specificity for African horse sickness antibodies detection using monovalent and polyvalent vaccine antigen-based dot blotting. Vet World 2022 Dec;15(12):2760-2763.
    5. More S, Bicout D, Bøtner A, Butterworth A, Calistri P, De Koeijer A, Depner K, Edwards S, Garin-Bastuji B, Good M, Gortazar Schmidt C, Michel V, Miranda MA, Nielsen SS, Raj M, Sihvonen L, Spoolder H, Thulke HH, Velarde A, Willeberg P, Winckler C, Bau A, Beltran-Beck B, Carnesecchi E, Casier P, Czwienczek E, Dhollander S, Georgiadis M, Gogin A, Pasinato L, Richardson J, Riolo F, Rossi G, Watts M, Lima E, Stegeman JA. Vector-borne diseases. EFSA J 2017 May;15(5):e04793.
      doi: 10.2903/j.efsa.2017.4793pubmed: 32625493google scholar: lookup
    6. Porphyre T, Grewar JD. Assessing the potential of plains zebra to maintain African horse sickness in the Western Cape Province, South Africa. PLoS One 2019;14(10):e0222366.
      doi: 10.1371/journal.pone.0222366pubmed: 31671099google scholar: lookup
    7. van de Water SG, van Gennip RG, Potgieter CA, Wright IM, van Rijn PA. VP2 Exchange and NS3/NS3a Deletion in African Horse Sickness Virus (AHSV) in Development of Disabled Infectious Single Animal Vaccine Candidates for AHSV. J Virol 2015 Sep;89(17):8764-72.
      doi: 10.1128/JVI.01052-15pubmed: 26063433google scholar: lookup
    8. Fall M, Diarra M, Fall AG, Balenghien T, Seck MT, Bouyer J, Garros C, Gimonneau G, Allène X, Mall I, Delécolle JC, Rakotoarivony I, Bakhoum MT, Dusom AM, Ndao M, Konaté L, Faye O, Baldet T. Culicoides (Diptera: Ceratopogonidae) midges, the vectors of African horse sickness virus--a host/vector contact study in the Niayes area of Senegal. Parasit Vectors 2015 Jan 21;8:39.
      doi: 10.1186/s13071-014-0624-1pubmed: 25604465google scholar: lookup
    9. Diarra M, Fall M, Fall AG, Diop A, Seck MT, Garros C, Balenghien T, Allène X, Rakotoarivony I, Lancelot R, Mall I, Bakhoum MT, Dosum AM, Ndao M, Bouyer J, Guis H. Seasonal dynamics of Culicoides (Diptera: Ceratopogonidae) biting midges, potential vectors of African horse sickness and bluetongue viruses in the Niayes area of Senegal. Parasit Vectors 2014 Mar 31;7:147.
      doi: 10.1186/1756-3305-7-147pubmed: 24690198google scholar: lookup
    10. Wilson AJ, Mellor PS. Bluetongue in Europe: past, present and future. Philos Trans R Soc Lond B Biol Sci 2009 Sep 27;364(1530):2669-81.
      doi: 10.1098/rstb.2009.0091pubmed: 19687037google scholar: lookup
    11. Wilson A, Mellor PS, Szmaragd C, Mertens PP. Adaptive strategies of African horse sickness virus to facilitate vector transmission. Vet Res 2009 Mar-Apr;40(2):16.
      doi: 10.1051/vetres:2008054pubmed: 19094921google scholar: lookup