3. A person or a doctor of medicine who studies human diseases as they affect the society. A person who studies epidemic disease.

4. Agent Factors Host Factors Environmental Factors Social Factors

5. Include the organisms that cause an infectious disease These can be; Bacteria Virus Ricketsiae Protozoa Fungi

9. Ricketsiae are tiny microorganisms much like bacteria. They are midway of bacteria and viruses having both characteristics. They live in the cell of host like mites, lice thick and fleas. These are carriers of diseases that infects man and animals.

11. Fungi are saprophytes and may be small single-celled like yeast Infections like athletes foot, ringworm are caused by skin fungus

12. Are attributes of individuals that may increase or decrease their susceptibility to certain disease They include genetic factor, immunity, health related behaviours and person’s general state of health. A host factor that offers special protection against disease is immunity

13. Are extrinsic biological, social, and physical factor that influence the probability of developing an infection.