Haemorrhagic septicaemia (HS) is an acute, fatal, septicaemic disease of cattle and water buffaloes (Bubalus bubalis) caused by a gram negative bacterium Pasteurella multocida, serotypes B:2 and E:2. The organism is capable of surviving in moist soil and water for up to 2-3 weeks.

Cattle and water buffaloes are the primary species affected and water buffaloes are considered to be highly susceptible. Animals between the ages of 6 and 24 months are the most severely affected during outbreaks. The disease has been reported in swine, fallow deer (Dama dama) and sporadically in horses, donkeys, elephant and yak.

Control of HS is best achieved through good husbandry practices, including acceptable plane of nutrition, increased awareness of the disease, early reporting systems and organized vaccination programs. Different types of vaccines have been developed. Vaccine types include inactivated oil-adjuvanted vaccines providing adequate protection between 9-12 months, and alum-precipitated vaccines with protection of up to 6 months.

Large scale vaccination of cattle against HS is not practised in many countries of Africa where the disease is endemic. During the past decade, considerable research has been conducted in South Asia aimed at producing oil adjuvant vaccines of low viscosity. Sri Lanka and Indonesia have successfully used lower levels of lanoline an emulsifying agent, in an effort to reduce viscosity.

Haemorrhagic septicaemia has a wide distribution with the highest occurrence in South East Asia. The disease is important in Africa, the Middle East and some countries in southern Europe. It has also been recognized in Japan and North America. The African form of haemorrhagic septicaemia occurs sporadically, it is limited in extent and appears to be associated with stress conditions. The B:2 serotype has been reported in southern Europe, the Middle East, South East Asia and North America. The E:2 serotype occurs primarily in Africa. Both B and E serotypes have been reported in the Sudan and in Egypt. Neither serotype has been found in South America, Central America, Australia or New Zealand.