The immunity that is transferred from maternal antibodies to the fetus trans-placentally and to the infant through breast milk to protect them until their own immune system matures to function is a kind of?

1. A

   Innate immunity

2. B

   Acquired immunity

3. C

   Active immunity

4. D

   Passive immunity

Appeared in: AIIMS Raipur NO - 2017 (Shift-1)

Explanation

• Passive Immunity because the fetus and infant are receiving 'ready-made' antibodies from the mother, rather than producing them on their own.
• This is a form of naturally acquired passive immunity.
• IgG antibodies are small enough to cross the placental barrier, providing protection to the fetus in utero.
• After birth, IgA antibodies are transferred to the infant through colostrum and breast milk, protecting the gastrointestinal tract.
• This protection is temporary and wanes as the maternal antibodies degrade, which is why the infant vaccination schedule is crucial.

Why Other Options Were Wrong

• Option A: Innate immunity refers to the non-specific, inborn defense mechanisms of the body, such as the skin, mucous membranes, and phagocytic cells. It does not involve the transfer of specific antibodies.
• Option B: Acquired immunity is a broad category that includes both active and passive immunity. While technically correct that this is a form of acquired immunity, 'Passive immunity' is the more specific and accurate answer describing the mechanism.
• Option C: Active immunity is the opposite of what is described. It occurs when the body is exposed to a pathogen (either through infection or vaccination) and produces its own antibodies and memory cells.

Related Visual

Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Types of immunity, specifically naturally acquired passive immunity as background academic context rather than a clinical decision trigger.
• Nurses play a vital role in educating new mothers about the immunological benefits of breastfeeding, as it provides essential IgA antibodies that protect the infant's gut from infections.
• Understanding the temporary nature of passive immunity is crucial for explaining the importance of adhering to the recommended childhood vaccination schedule to parents. This schedule is designed to stimulate the infant's own active immunity as maternal protection fades.
• What if? If an infant is born prematurely, they may have received fewer maternal IgG antibodies via the placenta, making them more vulnerable to infections. This highlights the increased importance of infection control measures and potentially the use of passive immunization products like palivizumab for RSV prevention in high-risk infants.

How to Approach the Question

• First, analyze the question to identify the core mechanism of immunity being described. The key phrase is 'transferred from maternal antibodies'.
• Recognize that the recipient (fetus/infant) is 'receiving' protection, not 'creating' it.
• Differentiate between the main types of immunity. 'Active' means the body is actively making antibodies. 'Passive' means the body is passively receiving them.
• Based on the keyword 'transferred', identify the process as passive.
• Evaluate the options. Innate immunity is non-specific. Active immunity is the opposite process. Acquired immunity is too general. Passive immunity perfectly describes the transfer of ready-made antibodies.
• Select 'Passive immunity' as the most precise and correct answer.

Concept Tested & Keywords

• Concept Tested: Types of immunity, specifically naturally acquired passive immunity.
• Stem keywords: immunity, maternal antibodies, fetus, trans-placentally, infant, breast milk
• Lead-in keywords: is a kind of
• Clinical cues: Age/sex group narrows the expected diagnosis, intervention, or normal reference range.
• Negative lead-in flag: false

Question ID

QC6bIMTCtKcu_cmZU5lbgB

Copy ID

Reference Book

E6 Microbiology Applied AnjuDhir 3e Part 2 p. 88-90

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart A (pp 26-201 of 604) p. 95-97

E6 Microbiology Essentials Sastry 4e Part 1 p. 137-139