Infectious disease & pathogens

Diseases such as malaria, cholera, tuberculosis and HIV/AIDS shape everyday life across Namibia and southern Africa, so in this lesson we learn what causes them and how to fight them. We begin by defining disease and separating infectious disease, caused by transmissible pathogens, from non-infectious disease such as sickle cell anaemia and lung cancer. We meet the three types of pathogen you must recognise — bacteria, protoctists and viruses — and put a name and type to each named disease: cholera (Vibrio cholerae), malaria (four Plasmodium species), TB (Mycobacterium tuberculosis and M. bovis), HIV/AIDS (HIV) and measles (Morbillivirus). We then follow how cholera, malaria, TB and HIV/AIDS are transmitted — by water, by the Anopheles mosquito, through the air, and through body fluids — and discuss the biological, social and economic factors in preventing and controlling each one. Finally we ask why malaria is found where it is, looking at climate, mosquito habitat, standing water and wealth.