Prevention of bovine respiratory syncytial virus infection and clinical disease by vaccination

Abstract

A double blind field trial was carried out with a live attenuated bovine respiratory syncytial virus vaccine. The trial involved 530 calves, two to 10 months old, on 27 dairy farms, where respiratory problems due to bovine respiratory syncytial virus infections had been observed during the preceding year. In 17 herds either all calves were vaccinated (nine groups) or all calves received a placebo (eight groups). In 10 herds half the number of calves were vaccinated and the other half kept as non-vaccinated controls. Calves were vaccinated intramuscularly twice with an interval of four to five weeks. These groups were under regular clinical observation and animals were tested periodically for antibodies to bovine respiratory syncytial virus and parainfluenza type 3 virus. Serological examination indicated that no bovine respiratory syncytial virus infection had occurred prior to the first vaccination in August. Vaccination did not cause adverse reactions. Low concentrations of neutralising and complement fixing antibodies were induced by vaccination and a sharp increase of antibody titres was observed after natural infection of vaccinated animals. Infections with bovine respiratory syncytial virus occurred in six out of eight non-vaccinated groups, in nine out of 10 partly vaccinated groups and in only two out of nine completely vaccinated groups. Virus infection in completely vaccinated groups was significantly reduced compared with partly vaccinated and non-vaccinated groups. The incidence of bovine respiratory syncytial virus lower respiratory disease was significantly reduced in completely vaccinated groups compared to non-vaccinated groups. Generally only mild signs of upper respiratory disease were present in completely vaccinated groups after bovine respiratory syncytial virus infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Protection against bovine respiratory syncytial virus challenge following a single dose of vaccine in young calves with maternal antibody

“…Field studies of early vaccination suggest that calves may be protected by either live or inactivated vaccines. In the Netherlands, Verhoeff and van Nieuwstadt (1984) gave calves two doses of vaccine before they were housed and challenged naturally, and observed a reduction of BRSV-associated disease. The calves were between two and 10 months of age when they were vaccinated but no data on the differences in the response or protection of calves with or without maternally derived antibody were given.…”

Animal Models of Respiratory Syncytial Virus Pathogenesis and Vaccine Development: Opportunities and Future Directions

“…Most such trials have been carried out in Europe; in one excellent example involving 530 calves on 27 farms, calves on farms where all calves were vaccinated with a modified live BRSV vaccine by intramuscular route had significantly decreased rates of BRSV infection and disease, compared to farms where calves were not vaccinated. Farms where half the calves were vaccinated had significantly decreased rates of disease but not infection (Verhoeff and van Nieuwstadt, 1984).…”

“…Because of the similarities between HRSV and BRSV, it should be possible to gain insight regarding factors that impact safety, efficacy, and duration of immunity in individuals vaccinated either in the presence or absence of circulating neutralizing antibodies using the BRSV model. Many published studies have shown that commercially available BRSV vaccines can induce protection against experimentally induced or naturally occurring BRSV disease (Durham and Hassard, 1990;Ellis et al, 2001;Van Donkersgoed et al, 1990b;Vangeel et al, 2007b;Verhoeff and van Nieuwstadt, 1984;West et al, 1999b;Xue et al, 2010).…”

“…Although BRSV vaccine ERD has been well-studied, extensive research and clinical experience indicate that BRSV vaccination can be safe and effective (Ellis et al, 1995;Ellis et al, 2005;Van Donkersgoed et al, 1990a;Vangeel et al, 2007a;Vangeel et al, 2009;Verhoeff and van Nieuwstadt, 1984;West et al, 1999b;Xue et al, 2010). In studies of resistance to experimental challenge, vaccination of calves with low or absent concentrations of serum neutralizing antibodies can protect them from virulent challenge.…”

Calf Pneumonia

“…Generally, only mild signs of upper respiratory tract disease were present in completely vaccinated groups following RSV infection. 61 In a recent study, an experimental inactivated RSV vaccine was compared with two live vaccines in a group of calves aged 4 to 8 months. 50 These calves had low or undetectable levels of maternal antibody to RSV.…”