UPSC Prelims 2010 Q128: Science & Technology – Health & Diseases
- (a) The chances of transmission from female to male are twice as likely as from male to female
- (b) The chances of transmission are more if a person suffers from other sexually transmitted infections
- (c) An infected mother can transmit the infection to her baby during pregnancy, at childbirth and by breast feeding
- (d) The risk of contracting infection from transfusion of infected blood is much higher than an exposure to contaminated needle
Answer: (a) The chances of transmission from female to male are twice as likely as from male to female
Explanation
HIV transmission: finding the incorrect statement
HIV transmission risk varies by route and biological factors, with some commonly misunderstood comparisons.
| Option | Verdict | Reason |
|---|---|---|
| (a) Female-to-male transmission is twice as likely as male-to-female | NOT correct | This is reversed: biologically, male-to-female transmission is generally MORE efficient than female-to-male, due to factors like semen's higher viral exposure during intercourse — not the other way around |
| (b) Chances are higher with other sexually transmitted infections | Is correct | Co-infection with other STIs increases transmission risk, a well-established finding |
| (c) An infected mother can transmit during pregnancy, childbirth, and breastfeeding | Is correct | This describes the recognized mother-to-child transmission routes |
| (d) Risk from infected blood transfusion is much higher than needle exposure | Is correct | Blood transfusion carries a very high transmission risk (close to certainty if infected blood is used), higher than typical needle-stick exposure risk |
HIV transmission facts:
| Point | Detail |
|---|---|
| Gender asymmetry | Male-to-female transmission is MORE efficient, not female-to-male |
| Other STIs | Increase transmission risk |
| Blood transfusion | Higher risk than needle-stick exposure |
Answer: (a) The chances of transmission from female to male are twice as likely as from male to female.
Why each option is right or wrong
- (a) CORRECT. This statement reverses the actual biological asymmetry — male-to-female transmission is generally more efficient, not female-to-male.
- (b) Incorrect. This statement is true: co-infection with other STIs does raise HIV transmission risk, so it's not the answer.
- (c) Incorrect. This statement is true: these are indeed recognized mother-to-child transmission routes.
- (d) Incorrect. This statement is true: transfusion of infected blood does carry a much higher risk than needle exposure.
Key point
HIV transmission is generally MORE efficient male-to-female than female-to-male — the opposite of what this statement claims, making it the incorrect one among otherwise accurate HIV transmission facts.
Remember
HIV transmission: male-to-female is MORE efficient than female-to-male — the opposite of the claim in this incorrect statement.
Common mistakes
- Reversing the actual gender asymmetry in HIV transmission efficiency.
- Missing the question's framing: it asks for the NOT correct statement among several true ones.
- Not knowing the comparatively higher risk from blood transfusion versus needle-stick exposure.
Exam tip
Male-to-female HIV transmission is MORE efficient than female-to-male — not the reverse. A key biological asymmetry fact, often tested in reverse.
Sources
- National AIDS Control Organisation — Annual Report 2009–10 (HIV/AIDS: modes of transmission)
- World Health Organization — HIV/AIDS: fact sheet