Vet on call: Dealing with anthrax scare on your farm
While the latter is periodic, occurring during wet seasons and mainly in some mapped-out areas, it can come in mild forms and easily infect people through inhalation of the viruses from open carcasses or through mosquito bites before it is diagnosed in animals.
Rabies infection in animals shows up dramatically either by causing the animal to drool saliva, become aggressive, vocalise abnormally and seek to bite things and people or just go unusually dull and quiet with swaying of the hind quarters. People get infected from animal bites or contact with body fluids.
Last week, I got a call from one Njuguna of Kahawa Sukari at about 11am. “Doctor, please come and help my friends because a bull they were expecting to feast on has just collapsed and died,” he said.
He explained the friends were a church-run children’s home and he was concerned that they did not seem to understand the implications of a sudden death in a cow. “You see, I read your article on anthrax and I am concerned it could be the problem,” he concluded.
I arrived on the farm late afternoon accompanied by Jane, an animal health student attached to my practice. The situation was as Njuguna had described. The cow had been fed water and kitchen waste in the morning and let out to graze in a field. The bull soon walked back to the closed gate, attempted to push it open before it collapsed and died.
The carcass lay at the edge of the plot close to the children’s home perimeter wall. Njuguna confirmed he had closely followed the instructions I gave on phone on removing the carcass from the gate to the current location. He had ensured nobody touched fluids from the carcass.
The bull had not been vaccinated against anthrax. Although the legs were sticking out, they were not stiff. I was able to fold the fore limbs at the carpal joint. This showed there was no rigor mortis — the stiffening that occurs after death. It is another good indicator of anthrax.
I was preparing to cut the nasal vein to observe the nature of blood when Jane urgently came to me and whispered, “Doctor, do you really want to open an anthrax carcass?” This was one of the days when she was required to observe cases, make her separate diagnosis and we compare notes before making the final diagnosis and intervention decision.
Care must be taken when cutting the blood vessel for the doctor to minimise chances of inhaling anthrax spores. The spores are formed as soon as the anthrax bacteria come into contact with air. Therefore, the cut must be small and the doctor must face the direction of the wind.
I opted for open burning and then burying the ash because the groundwater in the area was very close to the surface and it was also rocky. It would have been very difficult to bury the carcass the required two metres deep.
Using diesel, charcoal and hard wood, we incinerated the carcass in an open fire. Diesel is the fuel of choice because of its lower volatility and higher energy level compared to petrol. Petrol should never be used because it can spread fire through the wind or even burn the person lighting it.