This disease is caused by Pasteurella multocida type 1. It causes a form of acute pasteurellosis in bufallos and cattle.
Occurrence
Classical haemorrhagic septicaemia has been reported from all continents except Australia. The first regular occurrence is in the south east Asia where it appears every year with the monsoon rams and it is considered to be the most important infectious disease of cattle and domestic animals which are affected. Of the domestic animals, buffalos are the most susceptible followed by cattle.
Transmission
There is no satisfactory evidence that insect vectors are implicated or that infection persists in the soil. Healthy carriers of pasteurella organism have long been known in most susceptible species. About 5% of healthy cattle and buffalos are said to harbor the organism in the nasopharynx. Carriers or animals infected from them may under stress, breakdown into clear clinical cases. In the early clinical stage, there is salivation and nasal discharge containing numerous pasteurella organisms. The surrounding including drinking water becomes contaminated as bacteria can survive for some hours and the opportunity is there for other animals to become infected.
Clinical signs
Most cases in cattle and domestic buffalos are acute and sometimes peracute with death occurring 6-24 hours after the appearance of clinical signs. The first signs are dullness, reluctance to move about and fever. Salivation and nasal discharge appear. Commonly, swelling becomes visible around the laryngeal region and spreads around the head. The swelling is hot and doughy. The tongue may swell and protrude and mucous membranes are congested and breathing difficulty/respiratory distress appears. The animal usually goes down and dies within a few hours or lingers for 3-4 days. Recovery from the disease is rare.
Diagnosis
An outbreak of haemorrhagic septicaemia is readily identified but individual cases may be more difficult. The rapid cause of disease and higher occurrence of throat inflammation indicate haemorrhagic septicaemia. The lesions eliminate rinderpest, anthrax and black quarter. A snake bite near the head will simulate haemorrhagic septicaemia but such cases are rare. Confirmations of diagnosis can be made by examining blood films from muribond or recently dead animals and by sending materials to the laboratory for culture. Films are stained by Leishmann or Giemsa stain.
Treatment
To be effective, treatment must start before bacteraemia becomes well established. In later stages, although the organism can be killed by chemotherapy, the animal will nevertheless die. The organism is sensitive to sulfonamide and broad spectrum antibiotic but when clinical signs are obvious, the prognosis is usually grave.
Control
In endemic areas, vaccination is indicated and should be carried out yearly with vaccine known to confer long immunity like the oil adjuvant vaccine which can produce solid immunity lasting for about at least one year. Prior to the establishment of protective immunity, healthy animals should be segregated from the sick and in contact animals.
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