This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General, Subject name: Social & Preventive Medicine
Nosocomial infections are those which develop: 
Select and explain. 
A. 24 hours after hospitalization, B. Within 48 hours of hospitalization, C. After 48 hours of hospitalization, D. After 7 days of hospitalization
C: After 48 hours of hospitalization
Answer: C: After 48 hours of hospitalization 
Explanation: Ans. (c) After 48 hours of hospitalizationRef.: K. Park 23rd ed. / 94, 359* Nosocomial infections are hospital acquired infections.* It is considered nosocomial if it develops after a minimum of 48 hours of hospitalization.* Most common organism responsible for nosocomial infection: Staph. Aureus.