Question

A nosocomial (hospital-acquired) infection is defined as one occurring within how many hours of hospital admission?

• A. 48 hours
• B. 72 hours
• C. 24 hours
• D. 50 hours

Hint:

It is the same 2-day window used to call pneumonia ventilator-associated.

Answer 1

The Correct Option is A

Step 1: A hospital-acquired (nosocomial) infection is one that was neither present nor incubating at the time of admission.
Step 2: By the standard definition, an infection is called nosocomial when it appears more than 48 hours after admission, or within 3 days of discharge, or within 30 days of an operation.
Step 3: The 48-hour cut-off separates community-acquired infection (present or incubating on arrival) from one truly picked up in the facility. Common examples are ventilator-associated pneumonia, MRSA, catheter-associated UTI and C. difficile colitis.
So the answer is 48 hours.
Ref: Park Textbook of Preventive and Social Medicine; NCBI Bookshelf NBK441857.