Unless proper precautions are followed, pig, dog and cat manure can be harmful to human health. The composting process that can kill organisms harmful to man requires high temperatures and special conditions commonly not attained in Kenya and most developing countries.
The primary hazard present in pig and dog manure is parasites such as roundworms and tapeworms that can be passed on to man. Some resistant bacteria such as listeria and staphylococcus found in these animals, particularly the pig, may also survive the composting process and have been responsible for disease outbreaks in agricultural and livestock workers.
The risk involved in manure from these animals is not worthy the use in any crops that will be tendered by man. Cat feaces poses the greatest threat to human health because they may transmit Toxoplasmosis, a disease that is particularly hazardous for pregnant women, causing serious damage to the central nervous system (the brain) of an unborn child, resulting in foetal blindness, brain damage leading to retardation and other problems.
The adult parasite involved in this disease is carried only by cats, but the eggs, which are resistant to most environmental conditions, shed in the manure can infect humans, pigs, cows and other mammals.
The eggs remain viable in the soil for as long as 18 months, and the illness can be acquired through contact with infected cat manure or by ingesting the undercooked meat of an animal that has obtained the infection through grazing on pasture contaminated by cat faeces.
Therefore, cat manure, should always be handled with great care, and not at all by pregnant women and should never be used in food gardens.
For this reason, it is not advisable to use cat manure at all.
Dr Jane N. Maina, Veterinarian, Faculty of Veterinary Medicine and Surgery, Egerton University.