Transplacental transmission of the Italian Bluetongue virus serotype 2 in sheep


Bluetongue virus serotype 2
Culicoides cell line
Transplacental transmission

How to Cite

Spedicato, M., Carmine, I., Teodori, L., Leone, A., Casaccia, C., Di Gennaro, A., Di Francesco, G., Marruchella, G., Portanti, O., Marini, V., Pisciella, M., Lorusso, A., & Savini, G. (2019). Transplacental transmission of the Italian Bluetongue virus serotype 2 in sheep. Veterinaria Italiana, 55(2), 131–141. https://doi.org/10.12834/VetIt.1913.10140.1


In order to study the capability of a Bluetongue virus serotype 2 (BTV‑2) field isolate to cross the placental barrier, 2 groups of 5 pregnant ewes were infected with a field BTV‑2 Italian strain (Group A) or with the same strain passaged once in Culicoides cells (Kc) (Group B). Following infection, EDTA‑blood and serum samples were collected weekly and tested for the presence of BTV RNA/infectious virus and anti‑BTV‑2 antibodies, respectively. At lambing, precolostral EDTA‑blood and serum samples were collected from lambs and tested as before. The lambs were then sampled as scheduled for the dams. All sheep seroconverted on day 12 post‑infection (pi) and remained seropositive throughout the sampling period (day 68 pi). BTV was isolated from day 7 pi to day 14 pi in animals of Group A and from day 5 pi to day 12 pi in animals of Group B. None of the 14 lambs born had pre‑colostral antibodies. Three lambs born from two ewes of Group B were viraemic at birth and in one lamb infectious virus was isolated from blood up to 11 days of age. This study proved for the first time that a single passage of BTV‑2 field strain in Kc cells is able to give to BTV the ability to cross the placenta barrier and infect foetal tissues.


Backx A., Heutink R., van Rooij E. & van Rijn P. 2009. Transplacental and oral transmission of wild-type bluetongue virus serotype 8 in cattle after experimental infection. Vet Microbiol, 138, 235-243.

Barnard B.J. & Pienaar J.G. 1976. Bluetongue virus as a cause of hydranencephaly in cattle. Onderstepoort J Vet Res, 43(3), 155-157.

Batten C., Henstock M.R., Steedman H.M., Waddington S., Edwards L. & Oura C.A. 2013. Bluetongue virus serotype 26: infection kinetics, pathogenesis and possible contact transmission in goats. Vet Microbiol, 162, 62-67.

Bonneau K.R., Mullens B.A. & MacLachlan N.J. 2001. Occurrence of genetic drift and founder effect during quasispecies evolution of the VP2 and NS3/NS3A genes and bluetongue virus upon passage between sheep, cattle, and Culicoides sonorensis. J Virology, 75(17), 8298-8305.

Bonneau K.R., Demaula C.D., Mullens B.A. & MacLachlan, N.J. 2002. Duration of viraemia infectious to Culicoides sonorensis in bluetongue virus-infected cattle and sheep. Vet Microbiol, 88 (2), 115-125.

Bumbarov V., Golender N., Erster O. & Khinich Y. 2016. Detection and isolation of Bluetongue virus from commercial vaccine batches. Vaccine, 34, 3317–3323.

Caporale M., Di Gialleonardo L., Janowicz A., Wilkie G., Shaw A., Savini G., Van Rijn P.A., Mertens P., Di Ventura M. & Palmarini M. 2014. Virus and host factors affecting the clinical outcome of bluetongue virus infection. J Virology, 88(18), 10399–10411.

Dal Pozzo F., Saegerman C. & Thiry E. 2009. Bovine infection with bluetongue virus with special emphasis on European serotype 8. Vet J, 182(2), 142-151.

Darpel K.E., Batten C.A., Veronesi E., Williamson S., Anderson P., Dennison M., Clifford S., Smith C., Philips L., Bidewell C., Bachanek-Bankowska K., Sanders A., Bin-Tarif A., Wilson A.J., Gubbins S., Mertens P.P., Oura C.A. & Mellor P.S. 2009. Transplacental transmission of bluetongue virus 8 in cattle, UK. Emerg Infect Dis, 15(12), 2025-2028.

De Clerq K., Vandemeulebroucke E., Vanbinst T., De Leeuw I., Verheyden B., Goris N., Mintiens K., Meroc E., Herr C., Hooybergs J., Houdart P., Sustronck B., De Deken R., Maquet G., Bughin J., Saulmont M., Lebrun M., Bertels G. & Miry C. 2008a. Transplacental bluetongue infection in cattle. Vet Rec, 162, 564.

De Clercq K., De Leeuw I., Verheyden B., Vandemeulebroucke E., Vanbinst T., Herr C., Méroc E., Bertels G., Steurbaut N., Miry C., De Bleecker K., Maquet G., Bughin J., Saulmont M., Lebrun M., Sustronck B., De Deken R., Hooyberghs J., Houdart P., Raemaekers M., Mintiens K., Kerkhofs P., Goris N. & Vandenbussche F. 2008b. Transplacental infection and apparently immunotolerance induced by a wild-type bluetongue virus serotype 8 natural infection. Transbound Emerg Dis, 55(8), 352-359.

Domingo E. & Holland J.J. 1997. RNA virus mutations and fitness for survival. Annu Rev. Microbiol, 51, 151–178.

Elia G., Savini G., Decaro N., Martella V., Teodori L., Casaccia C., Di Gialleonardo L., Lorusso E., Caporale V. & Buonavoglia C. 2008. Use of real-time RT-PCR as a rapid molecular approach for differentiation of field and vaccine strains of bluetongue virus serotypes 2 and 9. Mol Cell Probes, 22, 38–46.

EFSA panel on animal health and welfare (AHAW). 2011. Scientific opinion on bluetongue serotype 8. EFSA J, 9(5), : 2189.

Eigen M. 1993. Viral quasispecies. Sci Am, 269, 42–49.

Elbers A.R.W., Backx A., Meroc E., Gerbier G., Staubach C., Hendrickx G., van der Spek A. & Mintiens K. 2008a. Field observations during the bluetongue serotype 8 epidemic in 2006 I. Detection of first outbreaks and clinical signs in sheep and cattle in Belgium, France and the Netherlands. Prev Vet Med, 87, 21–30.

Elbers A.R.W., Backx A., Mintiens K., Gerbier G., Staubach C., Hendrickx G. & van der Spek A. 2008b. Field observations during the Bluetongue serotype 8 epidemic in 2006 II. Morbidity and mortality rate, case fatality and clinical recovery in sheep and cattle in the Netherlands. Prev Vet Med, 87, 31–40.

Enright F.M. & Osburn B.I. 1980. Ontogeny of host response in ovine foetuses infected with bluetongue virus. Am J Vet Res, 41(2), 224-229.

Eschbaumer M., Wackerlin R., Rudolf M., Keller M., Konig P., Zemke J., Hoffmann B. & Beer M. 2010. Infectious blood or culture-grown virus: a comparison of bluetongue virus challenge models. Vet Microbiol, 146, 150–154.

Gibbs E.P.J., Lawman M.J.P. & Herniman K.A.J. 1979. Preliminary observations on transplacental infection of bluetongue virus in sheep – a possible overwintering mechanism. Res Vet Sci, 27, 118-120.

Goffredo M. & Meiswinkel R. 2004. Entomological surveillance of bluetongue in Italy: methods of capture, catch analysis and identification of Culicoides biting midges. Vet Ital, 40(3), 260-265.

Hansen P.J. 2013. Physiology and Endocrinology Symposium: maternal immunological adjustments to pregnancy and parturition in ruminants and possible implications for postpartum uterine health: is there a prepartum-postpartum nexus? J Anim Sci, 91(4), 1639-1649.

Hoffmann A.R., Dorniak P., Filant J., Dunlap K.A., Bazer F.W., de la Concha-Bermejillo A., Welsh C.J., Varner P. & Edwards J.F. 2013. Ovine fetal immune response to cache Valley virus infection. J Virology, 87(10), 5586-5592.

Hofmann M.A., Renzullo S., Mader M., Chaignat V., Worva G. & Thuer B. 2008. Genetic characterization of Toggenburg orbivirus, a new bluetongue virus, from goats, Switzerland. Emerg Inf Dis, 14, 1855-1861.

Kirkland P.D. & Hawkes R.A. 2004. A comparison of laboratory and ‘wild’ strains of bluetongue virus–is there any difference and does it matter? Vet Ital, 40 (4), 448-455.

Lefevre P.C., Mellor P.S. & Saegerman C. 2008. Bluetongue. In Infectious and parasitic diseases of livestock (S.A.S Lavoiser, ed). Provigny, France, 959-989.

Lelli R., Portanti O., Langella V., Luciani M., Di Emidio B. & Conte A. 2003. Produzione di un kit ELISA competitiva per la diagnosi sierologica della Bluetongue. Vet Ital, 47, 5-13.

Lorusso, A., Sghaier, S., Di Domenico, M., Barbria, M.E., Zaccaria, G., Legdich, A., Portanti, O., Seliman, I.B., Spedicato, M., Pizzurro, F., Carmine, I., Teodori, L., Mahjoub, M., Mangone, I., Leone, A., Hammami, S., Marcacci, M., Savini, G., 2018. Analysis of bluetongue serotype 3 spread in Tunisia and discovery of a novel strain related to the bluetongue virus isolated from a commercial sheep pox vaccine. Infect Genet Evol, 59, 63–71.

Maan S., Maan N.S., Nomikou K., Batten C., Antony F., Balaganahally M.N., Attia Mohamed Samy, Ammar Abdel Reda, Sana Ahmed Al-Rashid, Maha El Batel, Oura C.A.L. & Mertens P.P.C. 2011. Novel bluetongue virus serotype from Kuwait. Emerg Infect Dis, 17, 886-889.

MacLachlan N.J., Nunamaker R.A., Katz J.B., Sawyer M.M., Akita G.Y., Osburn B.I. & Tabachnick W.J. 1994. Detection of bluetongue virus in the blood of inoculated calves: comparison of virus isolation, PCR assay, and in vitro feeding of Culicoides variipennis. Arch Virol, 136(1-2), 1-8.

MacLachlan N,J,, Conley A.J. & Kennedy P.C. 2000. Bluetongue and equine viral arteritis viruses as models of virus-induced fetal injury and abortion. Anim Reprod Sci, 60-61, 643-651.

MacLachlan N.J., Crafford J.E., Vernau W., Gardner I.A., Goddard A., Guthrie A.J. & Venter E.H. (2008). Experimental reproduction of severe bluetongue in sheep. Vet Pathol, 45, 310–315.

MacLachlan N.J., Drew C.P., Darpel K.E. & Worwa G. 2009. The pathology and pathogenesis of bluetongue. J Comp Pathol, 141, 1-16.

Marcacci, M., Sant, S., Mangone, I., Goria, M., Dondo, A., Zoppi, S., van Gennip, R.G.P., Radaelli, M.C., Cammà, C., van Rijn, P.A., Savini, G., Lorusso, A., 2018. One after the other: a novel Bluetongue virus strain related to Toggenburg virus detected in the Piedmont region (North-western Italy), extends the panel of novel atypical BTV strains. Transbound Emerg Dis, 65, 370–374.

Mayo C.E., Crossley B.M., Hietala S.K., Gardner I.A., Breitmeyer R.E. & MacLachlan N.J. 2010. Colostral transmission of bluetongue virus nucleic acid among newborn dairy calves in California. Transb Emerg Dis, 57, 277-281.

Menzies F.D., McCullough S.J., McKeown I.M., Forster J.L., Jess S., Batten C., Murchie A.K., Gloster J., Fallows J.G., Pelgrim W., Mellor P.S. & Oura C.A.L. 2008. Evidence for transplacental and contact transmission of bluetongue virus in cattle. Vet Rec, 163, 203-209.

Méroc E., Herr C., Verheyden B., Hooyberghs J., Houdart P., Raemaekers M., Vandenbussche F., De Clercq K. & Mintiens K. 2009. Bluetongue in Belgium: episode II. Transbound Emerg Dis, 56(1-2), 39-48.

Mertens P.P. & Diprose J. 2004. The bluetongue virus core: a nano-scale transcription machine. Virus Res, 101, 29–43.

Miyasaka M. & Morris B. 1988. The ontogeny of the lymphoid system and immune responsiveness in sheep. Prog Vet Microbiol Immunol, 4, 21–55.

Oberst R.D. 1993. Viruses as teratogens. Vet Clin North Am Food Anim Pract, 9, 23-31.

Osburn B.I., Johnson R.T., Silverstein A.M., Prendergast R.A., Jochim M.M. & Levy S.E. 1971. Experimental viral-induced congenital encephalopathies. II. The pathogenesis of bluetongue vaccine virus infection in fetal lambs. Lab Invest, 25(3), 206-210.

Parsonson I.M., Della-Porta A.J., McPhee D.A., Cybinski D.H., Squire K.R. & Uren M.F. 1987. Bluetongue virus serotype 20: experimental infection of pregnant heifers. Aust Vet J, 64(1), 4-17.

Pedersen N.C., Liu H., Dodd K.A. & Pesavento P.A. 2009. Significance of coronavirus mutants in feces and diseased tissues of cats suffering from feline infectious peritonitis. Viruses, 1, 166-184.

Racicot K., Kwon J.Y., Aldo P., Silasi M. & Mor G. 2014. Understanding the complexity of the immune system during pregnancy. Am J Reprod Immunol, 72(2), 107–116.

Rasmussen L.D., Savini G., Lorusso A., Bellacicco A.L., Palmarini M., Caporale M., Rasmussesn T.B., Belsham G.J. & Bøtner A. 2013. Transplacental transmission of field and rescued strains of BTV-2 and BTV-8 in experimentally infected sheep. Vet Res, 44, 75-89.

Reed L.J. & Muench H. 1938. A simple method of estimating fifty percent endpoints. Am J Hyg, 27, 493-497.

Richardson C., Taylor W.P., Terlecki S. & Gibbs E.P. 1985. Observations on transplacental infection with bluetongue virus in sheep. Am J Vet Res, 46 (9), 1912-1922.

Saegerman C., Bolkaerts B., Baricalla C., Raes M., Wiggers L., De Leeuw I., Vandenbussche F., Zimmer J.Y., Haubruge E., Cassart D., De Clercq K. & Kirschvink N. 2011. The impact of naturally-occurring, transplacental bluetongue virus serotype-8 infection on reproductive performance in sheep. Vet J, 187, 72-80.

Santman-Berends I.M.G.A., Hage J.J., Van Rijn P.A., Stegeman J.A. & van Schaik G. 2010. Bluetongue virus serotype 8 (BTV-8) infection reduces fertility of Dutch dairy cattle and is vertically transmitted to offspring. Theriogenology, 74, 1377-1384.

Savini G., Hamers C., Conte A., Migliaccio P., Bonfini B., Teodori L., Di Ventura M., Hudelet P., Schumacher C. & Caporale V. 2009. Assessment of efficacy of a bivalent BTV-2 and BTV-4 inactivated vaccine by vaccination and challenge in cattle. Vet Microbiol, 133, 1-8.

Savini G., Di Gennaro A., Carvelli A., Pisciella M., Marini V., Lorusso A., Portanti O. & Scacchia M. 2012. BTV8 infections in pregnant cows during late gestation. In Proceedings of the 6th Epizone annual meeting edn, Brighton, UK: p. 21.

Savini G., Lorusso A., Paladini C., Migliaccio P., Di Gennaro A., Di Provvido A., Scacchia M. & Monaco F. 2014. Bluetongue serotype 2 and 9 modified live vaccine viruses as causative agents of abortion in livestock: a retrospective analysis in Italy. Transbound Emerg Dis, 61, 69-74. doi: 10.1111/tbed.12004. Epub 2012 Sep 3.

Savini G., Puggioni G., Meloni G., Marcacci M., Di Domenico M., Rocchigiani A.M., Spedicato M., Oggiano A., Manunta D., Teodori L., Leone A., Portanti O., Cito F., Conte A., Orsini M., Cammà C., Calistri P., Giovannini A. & Lorusso A. 2017. Novel putative Bluetongue virus in healthy goats from Sardinia, Italy. Infect Genet Evol, 51, 108–117.

Schultz G. & Delay P.D. 1955. Losses in newborn lambs associated with bluetongue vaccination of pregnancy ewes. J Am Vet Med Assoc, 127, 224-226.

Schulz C., Bréard E., Sailleau C., Jenckel M., Viarouge C., Vitour D., Palmarini M., Gallois M., Höper D., Hoffmann B., Beer M. & Zientara S. 2016. Bluetongue virus serotype 27: detection and characterization of two novel variants in Corsica, France. J Gen Virol, 97: 2073-2083. doi: 10.1099/jgv.0.000557. Epub 2016 Jul 19.

Shimshony A., Goldsmith L. & Barzilai E. 1980. Bluetongue in Israel. Bull Off Int Epiz, 92, 525-534.

Silverstein A.M., Uhr J.W., Kraner K.L. & Lukes R.J. 1963. Fetal response to antigenic stimulus. ii. antibody production by the fetal lamb. J Exp Med, 117, 799-812.

Stott J.L., Lauerman L.H. & Luedke A.J. 1982. Bluetongue virus in pregnant elk and their calves. Am J Vet Res, 43, 423-428.

Sun E.C., Huang L.P., Xu Q.Y., Wang H.X., Xue X.M., Lu P., Li W.J., Liu W., Bu Z.G. & Wu D.L. 2016. Emergence of a Novel Bluetongue Virus Serotype, China 2014. Transbound Emerg Dis, 63(6), 585-589.

Takamatsu H., Mellor P.S., Mertens P.P.C., Kirkham P.A., Burroughs J.N., Parkhouse RM. (2003). A possible overwintering mechanism for bluetongue virus in the absence of the insect vector. J Gen Virol, 84, 227-235.

Tizard I.R. 1996. Immunity in the fetus and newborn, p 237–250. In Veterinary immunology: an introduction, 5th ed. WBSaunders, Philadelphia, PA.

Van der Sluijs M.T., Timmermans M., Moulin V., Noordegraaf C.V., Vrijenhoek M., Debyser I., de Smit A.J. & Moormann R. 2011. Transplacental transmission of Bluetongue virus serotype 8 in ewes in early and mid-gestation. Vet Microbiol, 149(1-2), 113-25.

Van der Slujis M.T.W., Schroer-Joosten D.P.H., Fid-Fourkour A., Smit M., Vrijenhoek M.P., Moulin V., de Smit A.J. & Moormann R.J.M. 2013. Transplacental transmission of BTV-8 in sheep: BTV viremia, antibody responses and vaccine efficacy in lambs infected in utero. Vaccine, 31, 3726-3731.

Van der Sluijs M.T., de Smit A.J. & Moormann R.J. 2016. Vector independent transmission of the vector-borne bluetongue virus. Crit Rev Microbiol, 42(1), 57-64.

Verwoerd D.W. & Erasmus B.J. 2004. Bluetongue. In Infectious diseases of livestock, 2nd ed. (J.A. Coetzer & R.C. Tutsin, eds) RC. Oxford University Press, Cape Town, South Africa, 1201-1220.

White D.M., Wilson W.C., Blair C.D. & Beaty B.J. 2005. Studies on overwintering of bluetongue viruses in insects. J Gen Virol, 86, 453-462.

Wilson A., Darpel K. & Mellor P.S. 2008. Where does bluetongue virus sleep in the winter? PLoS Biol, 26;6(8):e210.

World Organisation for Animal Health (OIE). 2018. Bluetongue (infection with bluetongue virus). In Manual of Diagnostic Tests and Vaccines for Terrestrial Animals (Terrestrial Manual). (http://www.oie.int/fileadmin/Home/eng/Health_standards/tahm/3.01.03_BLUETONGUE.pdf/ accessed on 30 June 2019).

Wouda W., Peperkamp T., Roumen M., Muskens J., Van Rijn P.A. &Vellema P. 2009. Epizootic congenital hydranencephaly and abortion in cattle due to bluetongue virus serotype 8 in Netherlands. Tijdschr Diergeneeskd, 134, 422-427.

Zientara S., Sailleau C., Viarouge C., Höper D., Beer M., Jenckel M., Hoffmann B., Romey A., Bakkali-Kassimi L, Fablet A, Vitour D & Bréard E. 2014. Novel bluetongue virus in goats, Corsica, France, 2014. Emerg Infect Dis, 20(12), 2123-2125.