All are STDs except:

AIIMS Delhi NO-2016

Applied Microbiology & Infection control

Easy

Appeared in: AIIMS Delhi NO-2016

Explanation

Hepatitis A is primarily transmitted through the fecal-oral route, by ingesting contaminated food or water.
While sexual transmission (specifically oral-anal contact) can occur, it is not the primary mode of transmission, and Hepatitis A is classified as a food and water-borne illness.
The causative agent, Hepatitis A Virus (HAV), is an enterovirus shed in the feces of infected individuals, which differs from typical STD pathogens.

Option A: Gonorrhoea is a classic bacterial infection transmitted almost exclusively through sexual contact, making it a definitive STD.
Option C: AIDS is the late stage of infection with HIV, a virus that is primarily transmitted through sexual fluids and blood, placing it firmly in the category of STDs.
Option D: Syphilis is a bacterial infection caused by Treponema pallidum and is transmitted by direct contact with an infectious sore during sexual activity, defining it as an STD.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Classification of infectious diseases based on their primary mode of transmission as background academic context rather than a clinical decision trigger.
Understanding the exact transmission route is critical for nurses to provide correct patient education on prevention (e.g., hand hygiene and food safety for Hepatitis A vs. safe sex for HIV).
This knowledge directly impacts infection control protocols. For a patient with Hepatitis A, enteric precautions are key, whereas for other STDs, standard precautions and safe sex counseling are priorities.
What if the question asked about Hepatitis B? Hepatitis B is primarily transmitted through blood and sexual contact, making it a definite STD. In that case, it would be an incorrect answer for this 'except' question.

How to Approach the Question

First, identify the core concept being tested: modes of disease transmission, specifically sexually transmitted diseases (STDs).
Note the keyword 'except'. This is a negative question, meaning you are looking for the one option that does NOT fit the category of an STD.
Systematically evaluate each option based on your knowledge of infectious diseases.
Recall that Gonorrhoea, AIDS (caused by HIV), and Syphilis are classic examples of diseases primarily spread through sexual contact.
Consider Hepatitis A. Recall that it is most commonly associated with contaminated food and water, spreading via the fecal-oral route.
Conclude that because its primary transmission route is not sexual, Hepatitis A is the correct exception among the choices.

Concept Tested & Keywords

Concept Tested: Classification of infectious diseases based on their primary mode of transmission.
Stem keywords: STDs, except
Lead-in keywords: except
Negative lead-in flag: The question uses negative framing ('except'), asking to identify the option that is not a sexually transmitted disease.

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