Paper I — 2025 August (Supplementary) (2010 Scheme) — Q11

Paper I

2025 August (Supplementary) (2010 Scheme) · 40 marks · 120 min

Question

Name TWO modes of transmission of infection with examples for each

Q112 marksShort Notes★✓

Answer

Two modes of transmission of infection, with examples:

1. Direct transmission — the infectious agent passes directly from an infected host to a susceptible host without an intermediate vehicle or vector, e.g., droplet infection (respiratory droplets in influenza, pulmonary tuberculosis) and direct contact/sexual transmission (e.g., gonorrhoea, syphilis via sexual contact; direct skin contact in impetigo).

2. Indirect transmission — the infectious agent is transferred via an intermediate vehicle or vector, e.g., vector-borne transmission (mosquito-borne — malaria, dengue; tick-borne — Lyme disease) and vehicle-borne (common-vehicle) transmission via contaminated water or food (faecal-oral transmission of cholera, typhoid fever) or fomites (contaminated inanimate objects, e.g., surgical instruments).

(Other valid categorization: airborne transmission via droplet nuclei that remain suspended and travel further than large droplets, e.g., measles, chickenpox; vertical transmission from mother to child, e.g., transplacental transmission of syphilis/HIV.)

Related Concepts

1. 1Needle Stick Injury and Standard Precautions

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