Definition:
A communicable disease is a disease that spreads from one person, animal, or surface to another person. Examples of globally impactful communicable diseases include lower respiratory infections (e.g., pneumonia and bronchitis), COVID-19, tuberculosis, diarrheal diseases (e.g., cholera), and HIV/AIDS. The most common transmission routes include faecal-oral transmission, contaminated food, sexual contact, insect bites, contact with contaminated surfaces (fomites), droplets, and direct skin contact.
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