- Direct contact
- Infectious mononucleosis
- Lymphogranuloma venereum
- RSV, rhinovirus, Norwalk virus
- Droplet (>5 µm) (eg, coughing, sneezing)
- Influenza
- Meningococcal meningitis
- Adenovirus, pertussis
- Airborne (<5 µm) (eg, aerosols, ventilation system)
- Tuberculosis
- Measles, chickenpox, smallpox
- Vector-borne
- Mosquito: malaria, dengue, chikungunya, Zika virus
- Tick: Lyme disease, RMSF