Haemorrhagic septicaemia (HS) is the most common contagious bacterial infection of cattle and buffaloes in Pakistan. It is highly fatal disease with mortality rates above 70% inflicting economic losses of more than 2 billion rupees annually. Livestock breeders fear this disease the most.
Introduction
Haemorrhagic septicaemia (HS) is the most common contagious bacterial infection of cattle and buffaloes in Pakistan. It is highly fatal disease with mortality rates above 70% inflicting economic losses of more than 2 billion rupees annually. Livestock breeders fear this disease the most.
Clinical Picture Humoral immune response of oil based and Alum precipitated vaccine
The disease is caused by Pasteurella multocida serotype B:2. When clinical disease is established, death invariably occurs and case fatality rate is nearly 100%. Treatment is effective only in early stages of the disease. Vaccination is the most effective tool
for controlling this disease. It was observed that immunity conferred by conventional vaccine (alum precipitated bacterin) lasted for 3-4 months and therefore, three or more shots are required in a year for protecting the animals against H.S. Moreover, there were reports of outbreaks inspite of vaccination.
An oil based H.S vaccine was developed and its immunogenecity and protective efficacy was evaluated on state owned and private livestock farms. This vaccine provided a higher level of immunity for a longer duration i.e. for one year and its protective efficacy was more than 95%. After getting promising results the technology was transferred to private and public sector. Presently the vaccine is being produced by six public and ten private sector manufacturers. Furthermore, protective antigens of Pasteurella multocida were also determined.
Key References
Muneer, R. & Afzal, M. (1989). Preliminary Studies on improved oil adjuvant vaccine for Haemorrhagic septicaemia in buffalo calves. Rev. Sci. Tech. Off. Int. Epiz., 8(4) 999-1004.
Muneer, R., Akhtar, S. & Afzal, M. (1994). Evaluation of three oil adjuvant vaccines against Pasteurella multicida in buffalo calves. Rev. Sci. Tech. Off. Int. Epiz., 13(3) 837-843.
