Which of the following disease is not sexually transmitted?

1. Analyze the question You are asked to pick the disease that is NOT spread through sexual contact. So three options are sexually transmitted infections (STIs), and one is spread another way.

2. Explain the concept Sexually transmitted infections spread mainly through unprotected sexual contact (and sometimes from mother to child or through contaminated blood). Diseases like influenza spread through the respiratory route instead.

3. Go through each option

• A. Gonorrhea: caused by the bacterium Neisseria gonorrhoeae. It is an STI.
• B. Herpes: genital herpes is caused by the herpes simplex virus (HSV-2 mainly). It is an STI.
• C. Influenza: caused by the influenza virus. It spreads through airborne droplets from coughing and sneezing, and through contact with contaminated surfaces. It is not an STI.
• D. Syphilis: caused by the bacterium Treponema pallidum. It is an STI.

4. Answer The disease that is not sexually transmitted is Influenza, which is option C.

5. Exam tip Group diseases by how they spread:

• STIs: gonorrhea, syphilis, herpes, HIV/AIDS, chlamydia
• Airborne: influenza, tuberculosis, measles, common cold
• Water or food-borne: cholera, typhoid, dysentery
• Vector-borne: malaria, yellow fever, sleeping sickness

When a question says "not sexually transmitted," look for the one that fits a different group. Here, the "flu" is the odd one out.