Acta Tropica 160 (2016) 58–61 Contents lists available at ScienceDirect Acta Tropica journal homepage: www.elsevier.com/locate/actatropica Brucella abortus RB51 in milk of vaccinated adult cattle Karina Leite Miranda a , Fernando Padilla Poester a , Elaine Maria Seles Dorneles a,b , Thiago Magalhães Resende a , Adil Knackfuss Vaz c , Sandra Maria Ferraz c , Andrey Pereira Lage a,∗ a Laboratório de Bacteriologia Aplicada, Departamento de Medicina Veterinária Preventiva, Escola de Veterinária, Universidade Federal de Minas Gerais − UFMG, Avenida Antônio Carlos 6627, Caixa Postal 567, 31270-901, Belo Horizonte, MG, Brazil b Departamento de Medicina Veterinária, Universidade Federal de Lavras − UFLA, Avenida Dr. Sylvio Menicucci 1001, Caixa Postal 3037, 37200-000, Lavras, MG, Brazil c Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina − UDESC, Avenida Luís de Camões 2090, 88520-000, Lages, SC, Brazil a r t i c l e i n f o Article history: Received 14 January 2016 Received in revised form 20 April 2016 Accepted 23 April 2016 Available online 30 April 2016 Keywords: Cattle Milk Brucellosis Vaccine RB51 Vaccination a b s t r a c t The aim of this study was to evaluate the shedding of Brucella abortus in the milk of cows vaccinated with a full dose of RB51 during lactation. Eighteen cows, nine previously vaccinated with S19 as calves and nine non-vaccinated, were immunized subcutaneously with 1.3 × 10 10 CFU of B. abortus RB51, 30–60 days after parturition. Milk samples from all animals were collected daily until day 7, and at weekly interval for the next 9 weeks after vaccination. To evaluate the shedding of B. abortus, milk samples were submitted for culture and PCR. No B. abortus was isolated from any sample tested. Only one sample, collected on first day after vaccination from a cow previously vaccinated, was faintly positive in the PCR. In conclusion, the public health hazard associated with milk consumption from cows vaccinated with RB51 in post-partum is very low, despite vaccination with the full dose and regardless of previous S19 vaccination. © 2016 Elsevier B.V. All rights reserved. 1. Introduction Brucellosis caused by Brucella abortus is a chronic disease of cat- tle of worldwide economic and public health importance (Corbel et al., 2006). In Brazil, brucellosis is widely distributed (Poester et al., 2002), with herd prevalences ranging from 0.32% (Sikusawa et al., 2009) to 41.2% (Negreiros et al., 2009) among states. Vacci- nation of cattle is one of the most effective measure to reduce the prevalence of brucellosis, being successfully used in many control and eradication programs (Olsen and Stoffregen, 2005; Dorneles et al., 2015). Brucella abortus RB51 vaccine strain is a lipopolysaccharide O- antigen deficient mutant derived from the virulent strain B. abortus 2308, which does not induce an antibody response detectable by routine serological tests (Schurig et al., 1991). This feature allows RB51 vaccination to be performed at any age, while vac- cination with S19 is normally restricted to calves between 3 and 8 ∗ Corresponding author. E-mail addresses: karinalmi@gmail.com (K.L. Miranda), poesterf@terra.com.br (F.P. Poester), elaine.dorneles@dmv.ufla.br (E.M.S. Dorneles), thiago.violacaipira@gmail.com (T.M. Resende), adilvaz@gmail.com (A.K. Vaz), sandra@cav.udesc.br (S.M. Ferraz), alage@vet.ufmg.br (A.P. Lage). months of age (Brasil, 2006; Corbel et al., 2006). In Brazil, and in some other countries, RB51 is approved for vaccination of heifers older than 8 months (Poester and Gonc ¸ alves, 2006; Brasil, 2006, 2007). As the majority of the Brazilian adult cattle population was never vaccinated against brucellosis and the major current strat- egy of Programa Nacional de Controle e Erradicac ¸ ão de Brucelose e Tuberculose (National Program on the Control and Eradication of brucellosis and tuberculosis) (Brasil, 2006) is based on a vaccina- tion program using Strains 19 and RB51, the vaccination of lactating cows with RB51 is prone to become frequent. Hence, many concerns on the public health safety of RB51 vaccination of adult animals are raised, as there are only scanty data on the shedding of RB51 in the milk (Samartino et al., 1999; Samartino and Fort, 2000; Uzal et al., 2000). Additionally, the colonization of mammary gland and associated lymph nodes by B. abortus have been demonstrated (Carvalho-Neta et al., 2010), and organisms may be excreted in the milk (Xavier et al., 2009). Foodborne transmission of Brucella spp. is well known and is especially common through the consumption of raw milk and cheese made with unpasteurized milk (Godfroid and Cloeckaert, 2005). Considering the enormous importance of vaccination with RB51 for the control of bovine brucellosis and its possible impacts on http://dx.doi.org/10.1016/j.actatropica.2016.04.012 0001-706X/© 2016 Elsevier B.V. All rights reserved.