Recombinant hemagglutinin (HA) from a novel H1N1 influenza strain was produced using an alphavirus replicon expression system. The recombinant HA vaccine was produced more rapidly than traditional vaccines, and was evaluated as a swine vaccine candidate at different doses in a challenge model utilizing the homologous influenza A/California/04/2009 (H1N1) strain. Vaccinated animals showed significantly higher specific antibody response, reduced lung lesions and viral shedding, and higher average daily gain when compared to non-vaccinated control animals. These data demonstrate that the swine vaccine candidate was efficacious at all of the evaluated doses.

BackgroundBovine viral diarrhea virus is one of the most significant and costly viral pathogens of cattle worldwide. Alphavirus-derived replicon particles have been shown to be safe and highly effective vaccine vectors against a variety of human and veterinary pathogens. Replicon particles are non-propagating, DIVA compatible, and can induce both humoral and cell mediated immune responses. This is the first experiment to demonstrate that Alphavirus-based replicon particles can be utilized in a standard prime/boost vaccination strategy in calves against a commercially significant bovine pathogen.FindingsReplicon particles that express bovine viral diarrhea virus sub-genotype 1b E2 glycoprotein were generated and expression was confirmed in vitro using polyclonal and monoclonal antibodies specific to E2. Vaccine made from particles was generated in Vero cells and administered to BVDV free calves in a prime/boost regimen at two dosage levels. Vaccination resulted in neutralizing antibody titers that cross-neutralized both type 1 and type 2 BVD genotypes following booster vaccination. Additionally, high dose vaccine administration demonstrated some protection from clinical disease and significantly reduced the degree of leukopenia caused by viral infection.ConclusionsReplicon particle vaccines administered in a prime/boost regimen expressing BVDV E2 glycoprotein can induce cross-neutralizing titers, reduce leukopenia post challenge, and mitigate clinical disease in calves. This strategy holds promise for a safe and effective vaccine to BVDV.

Improved vaccines are necessary to prevent swine influenza, especially in young growing pigs. The objective of this study is to determine whether intranasal vaccination with Alphavirus replicon particle (RP) vector vaccine prevents influenza A virus (IAV) in pigs. RP vaccine was prepared with the hemagglutinin (HA) gene of pandemic H1N1 influenza virus (A/California/04/2009, pH1N1). The efficacy of intranasal (IN) administration with pH1N1 HA RP was evaluated in two pig experiments. In the first experiment, prime/boost RP vaccination was administered IN/IN to pigs. In the second experiment, pigs were administered a one dose intramuscular (IM) or IN HA RP vaccine, or with a combination of IN/IM routes with an interval of three weeks. Results showed that two doses IN administration of HA RP did not protect pigs against IAV; one dose IM and combination IN/IM routes vaccination with HA RP reduced pneumonia significantly and partially inhibited virus shedding following homologous challenge.

SUMMARYIntestinal health plays a major role in profitable and efficient turkey production. Blackhead disease (histomoniasis) is caused by Histomonas meleagridis, an anaerobic protozoan parasite. Histomonas meleagridis disrupts intestinal integrity and may cause systemic infection. Some field outbreaks of blackhead disease are associated with low morbidity and mortality, while in some instances, it may cause severe morbidity and mortality. In the current study, a presumptive diagnosis of blackhead disease was made based on the characteristic gross lesions in the liver and ceca. The cecal culture, PCR, and sequencing confirmed the presence of H. meleagridis and Pentatrichomonas hominis. Pentatrichomonas hominis has been reported in enteritis cases of several other species, such as dogs, cats, and cattle. The impact of P. hominis on intestinal health of turkeys has not previously been studied, and to the best of our knowledge, this is the first case report of concurrent H. meleagridis and P. hominis infection in turkeys.

and Implications Porcine Reproductive and Respiratory Syndrome (PRRS) imposes a huge financial burden on the swine industry. Thus, there is a clear and immediate need for improved PRRS virus (PRRSV) vaccines. Our group has proposed a new classification scheme for PRRSV strains that allows for immunological differentiation based on level of GP5 glycosylation. This classification based on glycantype has allowed us to choose PRRSV strains that offer the best chance of protection against PRRS.