14 words related to infections:
1. Epidemic - A widespread occurrence of an infectious disease
2. Pandemic - (of a disease) prevalent over a whole country or the world
3. Transmissible disease / communicable disease - An infectious disease transmissible (as from person to person) by direct contact
4. Immune system - the organs and processes of the body that provide resistance to infection and toxins
5. Viral infection - Infection caused by the presence of a virus in the body
6. Bacterial infection - An infection caused by bacteria
7. Dormant infection - Causing no symptoms but not cured and liable to recur
8. Acute infection - An infection that appears suddenly and may be of brief or prolonged duration
9. Contagious - (of a disease) spread from one person or organism to another by direct or indirect contact
10. Pathogen - A bacterium, virus, or other microorganism that can cause disease
11. Transmission - The conveyance of disease from one person to another
12. Diagnosis - The identification of the nature of an illness or other problem by examination of the symptoms
13. Host - an organism that harbors or nourishes another organism (the parasite)
14. Parasite - An organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense