What are the organs of immune system? Give a schedule of immunization for newborn children.
In short
The immune system's primary organs are the bone marrow and thymus, while secondary organs include the spleen, lymph nodes and tonsils. Under the Universal Immunisation Programme, newborns get BCG, OPV and Hepatitis B at birth, Pentavalent, OPV and rotavirus at 6, 10 and 14 weeks, and measles-rubella at 9 months.
Model answer
Ghissu Editorial · Verified 4 Oct 2026 · 281 words
Secondary Lymphoid Organs and MALT
Spleen filters blood pathogens; lymph nodes trap antigens from lymph fluid; tonsils and Peyer’s patches in the gut are key sites for immune activation. Mucosa-Associated Lymphoid Tissue (MALT), constituting about 50% of lymphoid tissue, protects mucosal surfaces where many infections enter.
Functional Coordination
These organs work together to initiate immune responses, enabling both innate and adaptive immunity essential for vaccine effectiveness.
Newborn Vaccines
The schedule includes BCG (tuberculosis), OPV (oral polio vaccine), Hepatitis B at birth, followed by Pentavalent vaccine (diphtheria, pertussis, tetanus, hepatitis B, Haemophilus influenzae type b), rotavirus and pneumococcal vaccines from 6 weeks and measles-rubella at 9 months, building active immunity.
Implementation Barriers
Challenges include vaccine hesitancy driven by misinformation, logistical difficulties in remote areas, and disparities between urban and rural coverage. Andhra Pradesh is addressing these through improved cold chain infrastructure and frontline health worker training.
Surveillance and Monitoring
Mission Indradhanush 4.0 enhances data collection and adverse event tracking, enabling timely interventions and improving vaccine coverage quality.
Community Engagement
Awareness campaigns via Anganwadi centres and local health workers help combat misinformation, increasing vaccine acceptance and demand among parents.
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Question from the official APPSC Group-I Mains 2012 paper. Answer written by Ghissu's engine and checked against our editorial standards. Found an error? Tell us and we correct it within 48 hours.