Raj. CHO -2024: Milk transmits all, except?

Raj. CHO -2024

Applied Microbiology & Infection control

Medium

Appeared in: Raj. CHO -2024

Explanation

Endemic typhus, also known as murine typhus, is not transmitted through the consumption of milk.
It is a classic vector-borne disease, caused by the bacterium Rickettsia typhi.
The primary mode of transmission to humans is through the infected feces of fleas, most commonly the rat flea (Xenopsylla cheopis), which gets rubbed into the bite site or other breaks in the skin.

Option B: Q fever can be transmitted through milk. The causative agent, Coxiella burnetii, is shed in the milk of infected animals such as sheep, goats, and cattle.
Option C: Typhoid fever can be transmitted through milk. Milk can become contaminated with Salmonella Typhi from the hands of an infected food handler (a carrier) or from contaminated water used to wash utensils or dilute the milk.
Option D: Brucellosis is a well-known milk-borne zoonosis. It is transmitted to humans through the ingestion of unpasteurized milk and dairy products (like cheese) from infected animals, primarily cattle, goats, and sheep.

Visual 1: Infographic: A comparative flowchart showing two transmission cycles. Side A illustrates the vector-borne cycle of Endemic Typhus (Rat -> Flea -> Human). Side B illustrates the food-borne cycle of Brucellosis (Infected Goat/Cow -> Unpasteurized Milk -> Human).

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Modes of disease transmission, specifically differentiating between milk-borne and vector-borne diseases as background academic context rather than a clinical decision trigger.
A key nursing role in community health is patient education on food safety. This includes advising the public to always consume pasteurized milk and dairy products to prevent zoonotic diseases like brucellosis and Q fever.
When taking a patient history for a fever of unknown origin, it is important to ask about dietary habits (like consumption of raw milk), occupational exposures (farming, veterinary work), and potential vector exposures (tick or flea bites).
What if? If a patient from a rural area presents with fever, sweats, and joint pain, and mentions drinking raw goat's milk, the nurse should have a high index of suspicion for Brucellosis and ensure this information is communicated to the physician.

How to Approach the Question

First, identify the keyword "except". This tells you that three of the options are correct for the given condition, and you must find the one that is incorrect.
The condition is "Milk transmits...". So, you are looking for the disease that is NOT transmitted by milk.
Evaluate each option: Is Q fever transmitted by milk? Yes. Is Typhoid fever transmitted by milk? Yes. Is Brucellosis transmitted by milk? Yes.
Evaluate the final option: Is Endemic typhus transmitted by milk? No, it's transmitted by fleas.
The option that does not fit the condition is the correct answer.

Concept Tested & Keywords

Concept Tested: Modes of disease transmission, specifically differentiating between milk-borne and vector-borne diseases.
Stem keywords: Milk, transmits
Lead-in keywords: except
Negative lead-in flag: Question asks for the exception

QAb8QSjnhxHolmDvxfnC2m

Textbook of Applied Microbiology Including Infection Control and Safety (Second Edition) p. 134-143