The prevalence of the three diseases namely malaria fever,
typhoid fever and bilharzia (schistosomiasis) comes about as a
result of the nature of the environment together with human
invasion of such an environment. The most important factor is
that, without the human invasion of the environment, there could
be no prevalence of these three diseases.ยท This, therefore,
suggests that humans have invaded the mosquito environment and
thus contracted malaria fever and spread the same to others.
Hum,ans have also invaded the water environment by contaminating
water with their excreta and thus spread typhoid fever and
bilharzia (schistosomiasis). The three diseases, malaria fever, typhoid fever, and bilharzia