Bovine respiratory disease (BRD) is a multifactorial syndrome causing major economic losses in the global cattle industry, exceeding USD 1 billion annually in North America alone. Four viruses play a key role: parainfluenza-3 virus (BPIV-3), infectious bovine rhinotracheitis virus (IBR, BHV-1), bovine viral diarrhea virus (BVDV), and bovine respiratory syncytial virus (BRSV). This theoretical review analyzes the scientific basis and modern approaches to the development of combined vaccines that simultaneously target all four pathogens. We discuss the advantages and disadvantages of inactivated (killed) versus live modified (attenuated/recombinant) vaccines, including their immunological mechanisms, adjuvant requirements, and vaccination schedules. Recent efficacy data from 2025–2026 field trials are presented, demonstrating significant reduction in viremia, fever, and lung lesions in vaccinated calves. The paper also places combined vaccination within an integrated BRD control strategy (biosecurity, nutrition, housing, genetic selection) and outlines future perspectives including mRNA vaccines, vector-based vaccines, DIVA vaccines, and inclusion of bacterial antigens. This work provides a theoretical foundation for the rational design of multivalent vaccines and their practical implementation in cattle farming.
Pavel Shulga (Fri,) studied this question.