Infectious Agent Transmission Flashcards

A hospital experiences a cluster of Aspergillus infections among immunocompromised patients during building renovation. What is the PRIMARY transmission concern?

Answer: Airborne fungal spores disturbed during construction

Construction activities disturb soil and building materials, releasing Aspergillus spores that travel via air to susceptible immunocompromised hosts.

Which droplet precaution characteristic distinguishes it from airborne precautions?

Answer: Droplets (>5 µm) travel only short distances and fall quickly, unlike airborne particles

Droplets >5 µm are too heavy to remain airborne for extended periods and typically travel only 3–6 feet before settling, unlike true airborne particles.

A patient with scabies requires which type of transmission-based precautions?

Answer: Contact precautions

Scabies mites are transmitted through prolonged direct skin-to-skin contact, requiring contact precautions including gloves and gowns.

The incubation period of an infectious disease is most relevant to transmission prevention because it:

Answer: Identifies the window during which a host may be infectious before symptoms appear

During the incubation period, individuals may shed pathogens and unknowingly transmit infection before becoming symptomatic, making this period critical for outbreak control.

Which of the following BEST describes indirect contact transmission?

Answer: Transmission through a contaminated intermediate object such as a shared blood pressure cuff

Indirect contact transmission involves transfer of an infectious agent via a contaminated inanimate object (fomite) that serves as an intermediate vehicle.

RSV (Respiratory Syncytial Virus) is primarily transmitted in healthcare settings through which route?

Answer: Large droplets and contact with contaminated surfaces

RSV spreads mainly through large respiratory droplets and direct or indirect contact with contaminated secretions on surfaces or hands.

An infection preventionist is investigating a foodborne outbreak. Which transmission category does this represent?

Answer: Common vehicle transmission

Foodborne outbreaks represent common vehicle transmission, where a single contaminated source (food or water) exposes multiple susceptible hosts simultaneously.