Microorganisms - Mosquitoes called vectors cary microorganisms that cause malaria. Malaria is caused by a protozoan that is a parasite as it gets food from its host, humans.
Lifestyle and diet can cause diabetes, no vitamin C causes scurvy, amaemia : not enough iron, some disorders are inherited eg red-green colourblindness.
We can prevent the spreadof malaria by understanding the lifecylce. Stagnant water kills the lava. Spraying insecterside kills them.
Cancer is a result of cells dividing out of control.
Binign tumour cells, such as warts are slow to divide and harmless
Malignant tumours are cancer cells, which divide out of control.