REGIONAL CONTROL PROGRAMMES AGAINST BHV1 TO OPTIMIZE ERADICATION OF INFECTION

1. Risk factors Basilicata Herds size OR 4.5 (2.7-9.9) Breeding OR 0.3 (0.1-0.6) seroprevalence 52% within herds seroprevalence 24% Vaccination 2% Risk factors Campania Heads introduction OR 2.9 (1.2-7.1) seroprevalence 47% within herds seroprevalence 46% Vaccination 5% Risk factors Piedmont Herds size OR 0.6 (0.4-0.8) Geographic position OR 2 (1.6-2.5) Heads introduction OR 1.9 (1.4-2.5) seroprevalence 70% within herds seroprevalence 56% Vaccination 30% Risk factors Sicily Heads introduction OR 7.6(2.3-25.1) seroprevalence 59% within herds seroprevalence 25% Vaccination 19% Risk factors Umbria Grazing OR 12 (3.8-27.1) Geographic position OR 5.1(1.2-21.8) seroprevalence 58% within herds seroprevalence 34% vaccination 15% Piedmont Umbria Campania Basilicata Sicily REGIONAL CONTROL PROGRAMMES AGAINST BHV1 TO OPTIMIZE ERADICATION OF INFECTION 2nd ESVV Veterinary Herpesvirus Symposium - Ghent (Belgium) , 2 – 4 March 2005 - • V. Quaranta*, F. Feliziani1, V. Caligiuri2, L. Chiavacci3, A. Guercio4, L. Masoero3, A. Mannelli5, D. Nava2, G. Purpari4, N. Vitale • *Istituto zooprofilattico sperimentale della Puglia e Basilicata, Potenza, Italy 1Istituto zooprofilattico sperimentale delle Marche e Umbria, Perugia, Italy2Istituto zooprofilattico sperimentale del Mezzogiorno, Portici, Italy 3Istituto zooprofilattico sperimentale del Piemonte, Torino, Italy 4Istituto zooprofilattico sperimentale della Sicilia, Palermo Italy 5Facoltà di Medicina Veterinaria, Torino, Italy • INTRODUCTION • In several countries BHV1 eradication or control programmes have been developed.123 These programmes are based on vaccination with DIVA (differentiating infected from vaccinated individuals) vaccines, or with inactivated or attenuated traditional vaccines used together with biosecurity measures. In order to investigate about BHV1 presence and persistence in cattle population and to develop a strategy to control BHV1 a cross sectional serological survey was carried out during 2002-2003 in 5 Italian regions: Piedmont, Sicily, Campania, Basilicata, Umbria. • MATERIALS AND METHODS • Dairy, beef and mixed cattle herds were included in a two-stage cluster sampling (herd and animal). Blood samples were collected during mandatory tests against bovine brucellosis. A questionnaire was administered to the farmer by public veterinarians at the time the blood collection, to gather information relative to herd size, introduction of cattle, breeding method, occurrence of immunization. The serum samples were tested for antibody against BHV1 by ELISA (Idexx® herdChek - Se 97 Sp 99.7). To identify predictors of seropositivity against BHV1 at herds level, a logistic regression model was performed. • RESULTS • Blood samples were collected from 24103 animals belong to 1050 herds. Of the selected herds, 310 (41.8%) were dairy herds, 243 (32.7%) mixed herds and 190 (25.5%) beef herds. Table 1 shows herd, within-herd sero-prevalence and risk factors for each region. Vaccination interested 29% of sampled herds in Piedmont, 19% of herds in Sicily, 15% of herds in Umbria, 6% in Campania and 2% in Basilicata. Vaccination was administered with inactivated (52%) and modified live vaccines (48%). Reproductive and respiratory disorders related to BHV1 were reported in Piedmont (10% of sampling), in Sicily (58%), in Umbria (6%), in Basilicata (16%) and in Campania (14%). • DISCUSSION • The 5 regions have a wide range of livestock productions and management so the probability of transmission of disease is different from Piedmont to Sicily or from Campania to Umbria or Basilicata. This agrees with presence of animals raised under different conditions of husbandry. Also vaccination strategies are performed in a different way in these areas. Based on result of this study we believe that control strategy based at regional level are more efficient so we suggest different BHV1 control programme that take into account for each region the differences on risk factors, BHV1 immunization and prevalence. • In Piedmont (70% BHV1+), a gE negative, killed vaccine could be used to protect sero – negative herds from inter herd virus transmission, whereas gE negative, live vaccines could be considered for negative animals of infected herds. During the initial phase of eradication, positive animals could be vaccinated with whole virus, killed vaccines to limit viral excretion. • In Campania (47% BHV1+, average herds size 35), a gE negative, killed vaccine could be used for seropositive herds. While vaccination could be avoided in negative herds and biosecurity measures of control could be considered for BHV1+ herds. For Basilicata (52% BHV1+, average herds size 31, within-prev 24% ), we considered vaccination with gE killed vaccines and a better controls on artificial insemination. In Sicily and Umbria (58 and 59% BHV1+ average herds size 70, mainly dairy herds), vaccination with gE negative, live vaccines could be suggested. • REFERENCE • De Wit, J.J., Hage, J.J., Brinkhof, J. and Westenbrink, F., 1998. A comparative study of serological tests for use in the bovine herpesvirus-1 eradication programme in The Netherlands. Vet. Microbiol. 61, pp. 153–163 • Solis-Calderon, J. J., Segura-Correa, V. M., Segura-Correa J. C. and Alvarado-Islas, A. (2003). Seroprevalence of and risk factors for infectious bovine rhinotracheitis in beef cattle herds of Yucatan, Mexico. Prev. Vet. Med. 57, 199-208 • F. Boelaert, P. Biront, B. Soumare, M. Dispas, E. Vanopdenbosch, J. P. Vermeersch, A. Raskin, J. Dufey, D. Berkvens and P. Kerkhofs. (2000). Prevalence of bovine herpesvirus-1 in the Belgian cattle population . Prev. Vet. Med. 45, 285-295 Tab. 1 risk factors and seroprevalence