An infectious disease is a transmissible disease that can be spread from one person to another
Pathogens are disease-causing organisms such as bacteria and virus
Virus:
An organism with a protein coat enclosing its genetic material and reproduces only in living host cells
Bacteria:
An organism with a cell wall and DNA without a nucleus
Some bacteria are pathogenic and some are non-pathogenic
A sign of a disease can be observed or measured. Examples are rashes, fever, coughing or vomiting
A symptom of a disease can be described or felt by the patient
Examples of symptoms are headaches, fatigue and nausea
A vaccine is an agent that resembles a pathogen and prevents infectious diseases by stimulating white blood cells to quickly produce antibodies when the pathogen invades
Antibiotics are drugs used to treat bacterial or fungal infections
Modes of transmission: air, direct contact with an infected person/surface, ingestion of contaminated food & water, vector transmits from one person to another