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📚 Your PSM Practica Exam Study Guide

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📖 PART 1: LITERATURE REVIEW (from your PDF - 30 slides)

What is a Literature Review?

"A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research."

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Why Do We Write a Literature Review? (Purpose)

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⭐ THE 5 KEY STEPS OF LITERATURE REVIEW (Most Important!)

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STEP 1: Search for Relevant Literature

• Online: PubMed, Google Scholar, Scopus
• Offline: Library books, journals
• Types of sources: journal articles, book chapters, conference papers, reports, reviews

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STEP 2: Evaluate Sources

1. What question/problem is the author addressing?
2. What are the key concepts and how are they defined?
3. What are the key theories, models, and methods?
4. Does the research use established frameworks or an innovative approach?
5. What are the results and conclusions?
6. How does it relate to other literature in the field?
7. Does it confirm, add to, or challenge existing knowledge?
8. What are the strengths and weaknesses?

Remember: Take notes and cite your sources (APA or Vancouver Style)

1. Read the abstract - decide if it's worth reading fully
2. Read the introduction - why is this study important?
3. Read the methods critically - focus on participants, measures, procedures
4. Evaluate the results - do conclusions seem logical? Any bias?
5. Take the discussion with a grain of salt - limitations are important

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STEP 3: Identify Themes, Debates, and Gaps

• What themes keep coming up?
• Where do researchers agree or disagree?
• What has NOT been studied yet? (That's the "gap" your research fills)

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STEP 4: Outline the Structure

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STEP 5: Write Your Literature Review

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Where Does the Literature Review Go in a Thesis/Dissertation?

• It comes near the beginning, after the introduction
• It grounds your research in the scholarly field
• It leads directly to your theoretical framework or methodology

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What is a Conceptual Framework?

1. Clarify concepts and propose relationships among them
2. Explain observations
3. Provide context for interpreting study findings
4. Encourage theory development useful to practice

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The Literature Review Summary Table (Template)

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Brain Storming Before Literature Search

• What to search?
• Where to search?
• How to search?
• Who is the expert locally in your department/hospital?
• What basic knowledge is needed?

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📖 PART 2: VALIDITY AND RELIABILITY (from your DOCX + PPTX)

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VALIDITY - "Does the test measure what it claims to measure?"

Types of Validity:

• Does the test cover ALL aspects of the topic?
• Example: A biology exam should include cell biology, genetics, evolution, AND ecology - not just one topic. If it only asks about cell biology, it lacks content validity.

• Convergent Validity: Related measures should actually be related (e.g., two intelligence tests should correlate)
• Discriminant Validity: Unrelated measures should NOT be related (e.g., intelligence test should NOT correlate with personality traits)

• Predictive Validity: Can the test predict a future outcome? Example: High SAT scores → higher college GPA. The SAT has good predictive validity.
• Concurrent Validity: Does it correlate with another established test taken at the SAME time? Example: A new depression test should give similar results to an already-established depression inventory.

• Does the test LOOK like it measures what it should?
• This is subjective - it's about appearance, not proof
• Example: A dietary habits questionnaire should ask about food intake, meal frequency, types of food.

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RELIABILITY - "Does the test give consistent results?"

Types of Reliability:

• Administer the SAME test to the SAME people at two different times
• Results should be similar
• Example: A personality test given today and again in 2 weeks should give similar scores

• Different raters/observers rating the SAME thing should agree
• Example: Two teachers grading the same essay should give similar marks

• Two DIFFERENT versions of the same test given to the same group should give similar results
• Example: Version A and Version B of a math test should produce similar scores

• Split-Half Reliability: Split the test into 2 halves; scores from both halves should be similar. Example: A 20-item anxiety test split into two 10-item sets.
• Cronbach's Alpha: A number (0-1) measuring how correlated items are. A value of 0.85 = high internal consistency (good)

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Why Are Validity AND Reliability Important?

Classic analogy: A clock that is always 10 minutes fast is reliable (consistent) but NOT valid (doesn't show correct time). A broken clock that randomly shows different times is neither reliable nor valid.

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Pre-testing

• Confusing or unclear questions
• Problems with the format
• Whether validity and reliability are adequate

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🔑 QUICK MEMORY TRICKS FOR THE EXAM

• Search for relevant literature
• Evaluate sources
• Identify themes, debates, and gaps
• Outline the structure
• Write your literature review

• AND = All terms (narrows)
• OR = Options (broadens)
• NOT = No that term (excludes)

• Content
• Construct (convergent + discriminant)
• Criterion (predictive + concurrent)
• Face

• Test-retest
• Inter-rater
• Parallel-forms
• Internal consistency (split-half + Cronbach's alpha)

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🎯 MOST LIKELY EXAM QUESTIONS & ANSWERS

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📄 LITERATURE REVIEW - QUICK REFERENCE

Definition

Survey of scholarly sources on a specific topic to identify theories, methods, and gaps.

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⭐ 5 STEPS (MEMORIZE THIS)

1. SEARCH     → Find relevant literature
2. EVALUATE   → Assess each source (Wh questions)
3. IDENTIFY   → Themes, debates, gaps
4. OUTLINE    → Choose structure
5. WRITE      → Intro + Body + Conclusion

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WHERE TO SEARCH

• Online: PubMed · Google Scholar · Scopus
• Offline: Books, journals, reports, conference papers

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BOOLEAN OPERATORS

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HOW TO READ AN ARTICLE (5 Steps)

1. Abstract - worth reading further?
2. Introduction - why important?
3. Methods - participants, measures, procedures
4. Results - logical? any bias?
5. Discussion - note limitations

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EVALUATE SOURCES (Wh Questions)

1. What problem is the author addressing?
2. What are the key concepts/definitions?
3. What theories, models, methods used?
4. Established or innovative approach?
5. What are results and conclusions?
6. How does it relate to other literature?
7. Confirms, adds to, or challenges knowledge?
8. Strengths and weaknesses?

Always: Cite sources in APA or Vancouver style

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4 STRUCTURES

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WRITING STRUCTURE

• Introduction - focus and purpose
• Body - summarize + synthesize + critically analyze
• Conclusion - key findings + significance

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POSITION IN THESIS

After introduction → before methodology. Grounds research, leads to theoretical framework.

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SUMMARY TABLE FORMAT

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CONCEPTUAL FRAMEWORK

• Diagram showing relationships between concepts
• Purpose: clarify concepts, explain observations, provide context, encourage theory development

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📄 VALIDITY & RELIABILITY - QUICK REFERENCE

VALIDITY = "Measures what it claims to measure"

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RELIABILITY = "Gives consistent results"

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KEY DIFFERENCE

Clock analogy: Clock always 10 min fast = Reliable ✓ but NOT Valid ✗

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PRE-TESTING

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• Steps: S-E-I-O-W
• Validity: C-C-C-F (Content, Construct, Criterion, Face)
• Reliability: T-I-P-I (Test-retest, Inter-rater, Parallel-forms, Internal consistency)

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• 📖 Definition + 5 Purposes (color-coded numbered boxes)
• ⭐ 5 Key Steps (S-E-I-O-W) - each step in its own color strip
• 🔍 Boolean Operators table (AND/OR/NOT with real examples)
• 📑 How to Read an Article (5-step reading guide)
• 🏗 4 Structures + Where in Thesis (side by side)

• 🎯 Validity types table with analogies (color-coded rows)
• 🔁 Reliability types table with analogies (color-coded rows)
• ⚖ Validity vs Reliability comparison table
• 🕐 Clock analogy box (highlighted in red)
• 🧪 Pre-testing section
• ❓ 8 likely exam Q&As
• 🧠 Final memory codes strip at the bottom

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📚 PSM PRACTICAL EXAM STUDY GUIDE

Chikungunya Fever | Malaria | Congenital Anomalies

(Based on Park's Textbook of Preventive & Social Medicine)

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🦟 TOPIC 1: CHIKUNGUNYA FEVER

What is it? (in simple words)

"Chikungunya" = Word from Kimakonde language (Tanzania) meaning "to become contorted" or "doubled up" - because joint pain is SO severe the patient walks bent over.

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Agent (Cause)

• Virus: Chikungunya virus - a single-stranded RNA virus, Alphavirus genus, Togaviridae family
• Also called a "Group A Arbovirus" (arthropod-borne virus)

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Epidemiology (How it spreads)

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Incubation Period

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Clinical Features (Signs & Symptoms)

1. High fever with chills
2. Severe joint pain (arthropathy) - the hallmark! Affects metacarpophalangeal joints, wrist, elbow, shoulder, knee, ankle - bilateral and symmetric
3. Headache (cephalalgia)
4. Backache (lumbago)
5. Morbilliform rash (measles-like rash) in 60-80% patients - on trunk and limbs - can recur every 3-7 days
6. Conjunctivitis
7. Lymph node enlargement (adenopathy)
8. Anorexia, nausea, vomiting

• Coffee-coloured vomiting
• Epistaxis (nosebleed)
• Petechiae

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Difference from Dengue (Examiner favourite!)

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Diagnosis

• Clinical - history + features
• RT-PCR - within first week (detects virus)
• IgM antibodies - develop end of first week, persist 30-90 days
• Plaque-Reduction Neutralization Test (PRNT) - reference test at CDC

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Treatment

• NO specific antiviral available
• Supportive treatment:
  • Rest + fluids
  • Paracetamol or Diclofenac sodium for fever and joint pain
  • Chloroquine has been used
  • Avoid Aspirin and Steroids (important!)
  • NSAIDs - avoid initially (rule out dengue first)
  • Physiotherapy for persistent joint pain
  • Methotrexate/Hydroxychloroquine for severe persistent arthritis

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Prevention & Control

• No vaccine available (as of Park's edition)
• Vector control: Eliminate Aedes mosquito breeding sites
• Personal protection: insect repellent, long sleeves, screened dwellings
• Protect febrile patients from mosquito bites (to stop further spread)
• Reportable disease - notify to state/local health department

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Memory Trick

CHIK = Contorted, Hot, Insect (Aedes), Knees (joints)

• C: Contorted = severe joint pain (the name)
• H: High fever, sudden onset
• I: Insect = Aedes mosquito
• K: Knees + all joints = arthropathy is the hallmark

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🦟 TOPIC 2: MALARIA

What is it? (in simple words)

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Agent (Cause)

India: P. falciparum is the main killer - it's drug resistant and causes complications

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Epidemiology

1. Young children (not yet immune)
2. Non-immune pregnant women (causes miscarriage, maternal death)
3. HIV patients
4. International travellers (no immunity)
5. Tribal populations in forest/border areas

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Classic Clinical Features - The "Malarial Paroxysm"

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Complications of Malaria (Mainly P. falciparum)

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Diagnosis

1. Thick blood smear (gold standard) - done during fever
2. Thin blood smear - species identification
3. Rapid Diagnostic Test (RDT) - HRP-2 antigen for P. falciparum
4. PCR - most sensitive
5. Widal test - NOT for malaria (common mistake)

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Treatment (ACT is the KEY)

• ACT = Artemisinin-based Combination Therapy (e.g., Artesunate + Amodiaquine)
• Severe malaria: IV Artesunate or IV Quinine

• Chloroquine (14 days)
• Plus Primaquine (for radical cure - to kill liver hypnozoites and prevent relapse)

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Prevention & Control

1. Vector Control (Most important in PSM!)

• IRS = Indoor Residual Spraying of insecticides (DDT, Malathion)
• ITN = Insecticide-Treated Nets / Long-Lasting Insecticidal Nets (LLINs)
• Larval control: anti-larval measures (oil, larvicides, draining stagnant water)
• Biological control: Gambusia fish (eats larvae)

2. Personal Protection

• Bed nets, repellents (DEET)
• Protective clothing

3. Chemoprophylaxis (for travellers)

• Chloroquine (where sensitive), or Doxycycline/Mefloquine

4. Vaccine

• RTS,S/AS01 (Mosquirix) - first approved malaria vaccine (WHO approved 2021, for P. falciparum, for children in sub-Saharan Africa)

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National Programme

• Controls malaria, dengue, chikungunya, kala-azar, filaria, JE in India
• Strategies: early diagnosis, prompt treatment, IRS, ITN, epidemiological surveillance

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Memory Trick for Malaria

"FACT" = Falciparum is the most dangerous, Anopheles female transmits, Cold-Hot-Sweating are 3 stages, Treatment is ACT

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👶 TOPIC 3: CONGENITAL ANOMALIES

What is it? (in simple words)

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Definitions (Know the difference!)

WHO document 1972: "Congenital anomaly" is the broader term - includes biochemical, structural, and functional disorders.

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Incidence (Park's PSM figures)

• Affects approximately 1 in 33 infants
• Causes 3.2 million birth defect-related disabilities every year
• 270,000 newborns die in the first 28 days of life each year from congenital anomalies

1. Heart defects (most common)
2. Neural tube defects (NTDs - e.g., spina bifida, anencephaly)
3. Down syndrome

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Causes (Etiology)

1. Genetic Factors

2. Environmental Factors (Teratogens)

Remember TORCH infections: Toxoplasma, Other (syphilis, HIV, Parvovirus), Rubella, CMV, Herpes

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Risk Factors

1. Advanced maternal age - main risk for Down syndrome (risk = 1:67 at age 40-45 vs 1:800 overall)
2. Consanguineous marriages (first cousin, uncle-niece) - increases risk of mental retardation and malformations
3. Previous malformed child - risk in next pregnancy is 10x higher
4. Drug exposure in first trimester
5. Infections in first trimester

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Types of Presentation

• Obvious at birth: Cleft palate, cleft lip
• Obvious in early life: Congenital dislocation of hip (CDH)
• Detected later: Patent ductus arteriosus (PDA)
• Major: Need surgical intervention
• Minor: No functional implication (e.g., skin tag in front of ear)

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Prenatal Diagnosis (Very important for PSM exam!)

CVS vs Amniocentesis: CVS is done earlier (9-11 weeks) vs amniocentesis (after 12 weeks)

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Prevention - 3 Main Approaches (Park's)

1. Discourage further reproduction after birth of a malformed child (risk 10x higher in next pregnancy)
2. Avoid pregnancy in high-risk circumstances:
   • Advanced maternal age (Down syndrome risk)
   • Consanguineous marriages
3. Identify and remove teratogens:
   • Avoid drugs in pregnancy (especially first trimester)
   • Treat infections (rubella vaccination - now routine in many countries)
   • Avoid X-rays, radiation
   • Folic acid supplementation before and during pregnancy (prevents NTDs)
   • Avoid alcohol, tobacco

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Surveillance

• Birth defects surveillance is key for public health planning
• Penrose (1961): Major advances in prevention must come from environmental factors (not genetic control)

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Memory Trick

"GEMS" for causes:

• Genetic (chromosomal, inborn errors, single gene)
• Environmental infections (TORCH)
• Maternal conditions (diabetes, radiation)
• Substances/drugs (thalidomide, alcohol, folate deficiency)

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🔑 QUICK COMPARISON TABLE (Examiner Favourite)

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🧠 ALL MEMORY TRICKS TOGETHER

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❓ MOST LIKELY EXAM QUESTIONS

• Q: Define chikungunya. What does the name mean? → "Doubled up / contorted" due to joint pain; Tanzania 1952-53
• Q: Vector of chikungunya? → Aedes aegypti and Aedes albopictus
• Q: Treatment of chikungunya? → Supportive; Paracetamol; avoid Aspirin & Steroids
• Q: How is chikungunya different from dengue? → Joint pain more severe; no deaths; chronic arthritis

• Q: Define malaria / causative agent? → Protozoal disease caused by Plasmodium, transmitted by female Anopheles
• Q: What are the 3 stages of malarial paroxysm? → Cold → Hot → Sweating
• Q: Most dangerous species? → P. falciparum (cerebral malaria, blackwater fever)
• Q: Treatment of P. falciparum malaria? → ACT (Artemisinin-based Combination Therapy)
• Q: What is NVBDCP? → National Vector Borne Disease Control Programme

• Q: Definition of congenital anomaly (WHO)? → All structural, biochemical, and functional disorders present at birth
• Q: Incidence? → 1 in 33 infants; 270,000 neonatal deaths/year
• Q: 3 approaches to prevention? → Discourage reproduction after malformed child; avoid pregnancy in high-risk; remove teratogens
• Q: Teratogens you must name? → Thalidomide, Rubella, Folic acid deficiency, X-rays, Alcohol
• Q: CVS vs Amniocentesis? → CVS at 9-11 weeks; Amniocentesis after 12 weeks
• Q: Risk factor for Down syndrome? → Advanced maternal age (risk 1:67 at age 40-45)

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• Definition, name origin, first isolation
• Agent + Epidemiology side by side
• Clinical features table
• Diagnosis + Treatment side by side
• Warning box: AVOID Aspirin & Steroids
• Memory box

• Definition
• 4 Plasmodium species table (P. falciparum highlighted as dangerous)
• Malarial paroxysm stages + Complications side by side
• Diagnosis table (thick smear, RDT, API/ABER/SPR)
• Treatment table (ACT for falciparum, Chloroquine+Primaquine for vivax)
• Prevention table (IRS, LLIN, Gambusia, RTS,S vaccine, NVBDCP)
• Memory box

• WHO definition
• Stats boxes: 1 in 33 infants • 3.2 million • 270,000 deaths
• Causes: Genetic vs Environmental side by side
• Risk factors table
• Prenatal diagnosis + 3 Prevention approaches side by side
• Memory box (GEMS, TORCH)

• Chikungunya vs Malaria comparison table
• 14 most likely exam Q&As (colour-coded by topic)
• Bottom memory strip with all key mnemonics

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🟡 YELLOW FEVER — PSM EXAM STUDY GUIDE

Based on Park's Textbook of Preventive & Social Medicine

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WHAT IS YELLOW FEVER? (Simple Definition)

Park's Definition: "A zoonotic disease caused by an arbovirus. It affects principally monkeys and other vertebrates in tropical America and Africa and is transmitted to man by certain culicine mosquitoes. It is characterized by more severe hepatic (liver) and renal (kidney) involvement."

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PROBLEM STATEMENT (Global Burden)

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EPIDEMIOLOGICAL TRIAD (PSM Framework)

(A) AGENT FACTORS

(B) HOST FACTORS

(C) ENVIRONMENTAL FACTORS

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INCUBATION PERIOD

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CLINICAL FEATURES (Stages of Yellow Fever)

Stage 1 — Infection (Acute Phase, Days 1-3)

• Sudden onset of high fever
• Headache, backache, muscle aches
• Nausea, vomiting
• Loss of appetite

Stage 2 — Remission (Brief improvement, Hours to 1 day)

• Fever falls
• Patient seems to be getting better
• Most patients recover at this stage

Stage 3 — Intoxication (Toxic Phase — Severe cases)

• Jaundice (liver damage) — this gives the disease its NAME "Yellow Fever"
• Haemorrhagic manifestations:
  • "Black vomit" (vomiting of digested blood — very characteristic!)
  • Epistaxis (nosebleed)
  • Melena (blood in stool)
• Albuminuria or anuria (kidney failure — protein/no urine)
• Shock
• Agitation, stupor, coma
• Death — between 5th and 10th day of illness

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MODES OF TRANSMISSION — 3 CYCLES (Very Important!)

Most common outbreak type in Africa: Intermediate cycle Most dangerous type: Urban cycle (large epidemics, human-to-human spread via Aedes aegypti) Jungle yellow fever is UNCONTROLLABLE — no practical measures exist

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TREATMENT

• NO specific antiviral treatment available
• Only supportive care:
  • Treat dehydration
  • Treat fever
  • Antibiotics for associated bacterial infections
  • ICU support for severe cases

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CONTROL OF YELLOW FEVER

1. VACCINATION (Most important!)

"Rapid immunization of the population at risk is the most effective control strategy for yellow fever."

Who should NOT be vaccinated?

1. Children under 9 months (routine); under 6 months during epidemic
2. Pregnant women — except when risk of infection is high during outbreak
3. People with severe egg protein allergy
4. People with severe immunodeficiency (symptomatic HIV/AIDS, thymus disorder)

Post-vaccinial reactions:

• Mild reactions (myalgia, headache, low-grade fever) in 2-5% of vaccinees, appearing 5-10 days after vaccination
• Anaphylaxis is very rare (mainly in those allergic to eggs)

Important Note:

Cholera vaccine and Yellow Fever vaccine given together (or within 3 weeks) interfere with each other — give them at least 3 weeks apart!

2. VECTOR CONTROL

• Control Aedes aegypti (peri-domestic mosquito)
• Anti-adult measures (insecticides)
• Anti-larval measures (eliminate breeding sites)
• "Source reduction" — long-term policy (eliminate breeding places)
• Health education

Aedes aegypti Index:

• A house index = "Percentage of houses and their premises in a defined area showing actual breeding of Aedes aegypti larvae"
• Should NOT exceed 1% in towns and seaports in endemic areas to ensure freedom from yellow fever

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INDIA AND YELLOW FEVER — KEY PSM Facts

1. Population is unvaccinated and susceptible
2. Vector Aedes aegypti is found in abundance in India
3. Climate is favourable for transmission in most parts
4. The common monkey of India (Macacus spp.) is susceptible to yellow fever
5. The only missing link is the yellow fever virus itself — it does not currently occur in India

1. Through infected travellers (clinical and subclinical cases)
2. Through infected mosquitoes on aircraft/ships

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INTERNATIONAL MEASURES (IHR)

For Travellers:

• All travellers from/through yellow fever endemic zones must have a valid International Certificate of Vaccination
• If no certificate: placed in quarantine in a mosquito-proof ward for 6 days
• Certificate validity starts 10 days after vaccination
• Since 11th July 2016 (IHR amendment, May 2014): Certificate valid for the LIFETIME of the person (previously 10 years)
• No booster/revaccination required for international travel as of 2016

For Aircraft/Ships:

• Aerosol spraying with insecticides on arrival from endemic areas
• Airports and seaports kept free of vector breeding for at least 400 metres around their perimeters
• Aedes aegypti index must be kept below 1%

India's requirement:

• Valid certificate required from travellers coming from infected areas
• Required even if the traveller was only in transit
• Required for infants ≥9 months of age

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EYE STRATEGY (Elimination Yellow Fever Epidemics)

1. Protect at-risk populations
2. Prevent international spread of yellow fever
3. Contain outbreaks rapidly

1. Affordable vaccines and sustained vaccine market
2. Strong political commitment (global, regional, country)
3. High-level governance with long-term partnerships
4. Synergies with other health programmes
5. Research and development for better tools

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DIAGNOSIS

A confirmed case of yellow fever in an unvaccinated population = potential outbreak = need for emergency vaccination campaign

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YELLOW FEVER ENDEMIC COUNTRIES (Know these for exam)

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🧠 MEMORY TRICKS

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❓ MOST LIKELY EXAM QUESTIONS & ANSWERS

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⚡ QUICK SUMMARY TABLE (One-page Glance)

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💉 IMMUNIZATION vs VACCINATION

Complete PSM Exam Study Guide

(Based on Park's Textbook of Preventive & Social Medicine)

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STEP 1 — UNDERSTAND THE BASIC DIFFERENCE FIRST

Simple analogy: Vaccination is like planting a seed. Immunization is when the tree has grown and is bearing fruit (protection). You can't have immunization without first having vaccination — but vaccination alone doesn't guarantee immunization (because not everyone responds to every vaccine).

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KEY DEFINITIONS (Park's PSM)

Vaccine

"An immuno-biological substance designed to produce specific protection against a given disease. It stimulates the production of protective antibody and other immune mechanisms."

• Vaccines may be prepared from: live modified organisms, inactivated/killed organisms, extracted cellular fractions, toxoids, or combinations.

Vaccination

• The act of administering a vaccine — giving the injection, oral drop, or spray
• It is a physical process

Immunization

• The process by which an individual is made immune or resistant to an infectious disease
• Includes both vaccination AND the body's response to it
• It is a biological process
• Immunization can also happen through natural infection

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THE BIG DIFFERENCE TABLE (Most Exam-Friendly Format)

Exam tip: Immunization is the broader term — it includes vaccination as one of its methods. Vaccination is just one WAY to achieve immunization.

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TYPES OF IMMUNIZATION

TYPE 1 — ACTIVE IMMUNIZATION

Park's: "Active immunization is one of the most powerful and cost-effective weapons of modern medicine."

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TYPE 2 — PASSIVE IMMUNIZATION

1. Normal human immunoglobulin — general protection
2. Specific (hyperimmune) human immunoglobulin — against specific disease
3. Antisera or anti-toxins — animal-derived (e.g., anti-snake venom)

• Duration is short and variable (1–6 weeks)
• Undesirable reactions may occur (especially if antiserum is of non-human origin)
• Limited value in mass control of disease

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TYPE 3 — COMBINED (Passive + Active) Immunization

Important rule: Immunoglobulin should NOT be given within 3 weeks BEFORE or until 2 weeks AFTER a live attenuated vaccine — they interfere! (Exception: Hepatitis B vaccine + Hepatitis B immunoglobulin can be given together)

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COMPLETE CLASSIFICATION OF IMMUNIZATION

IMMUNIZATION
├── ACTIVE
│   ├── Natural (through infection)
│   └── Artificial (through vaccination)
│       ├── Live attenuated vaccines
│       ├── Killed/inactivated vaccines
│       ├── Toxoids
│       └── Subunit/recombinant vaccines
└── PASSIVE
    ├── Natural (maternal antibodies to infant)
    └── Artificial (immunoglobulins, antisera)

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TYPES OF VACCINES (Very Important!)

A. LIVE VACCINES (Live Attenuated)

• Single dose usually enough
• Long-lasting immunity (mimics natural infection)
• Produces both IgA + IgG
• Produces mucosal immunity + cell-mediated immunity
• No adjuvant needed

• Heat sensitive — need cold chain
• Can revert to virulence (e.g., VAPP from OPV)
• Contraindicated in immunodeficient, pregnant, cancer patients

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B. KILLED / INACTIVATED VACCINES

• Safe (cannot cause disease)
• Stable — no strict cold chain issues
• Safe in immunocompromised and pregnant patients

• Multiple doses needed
• Shorter duration of immunity
• Adjuvant often needed
• Only IgG produced (no mucosal/cellular immunity)

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LIVE vs KILLED VACCINE COMPARISON (Park's Table 30)

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C. TOXOIDS

• Diphtheria toxoid (in DPT)
• Tetanus toxoid (TT)

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D. SUBUNIT / RECOMBINANT VACCINES

• Hepatitis B vaccine (recombinant — uses HBsAg protein)
• HPV vaccine (virus-like particles)
• Acellular pertussis (DTaP)

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HERD IMMUNITY (Park's PSM Definition)

Park's definition: "Herd immunity (or community immunity) describes a type of immunity that occurs when the vaccination of a portion of population provides protection to unprotected individuals."

• More immune people → harder for the virus to find a susceptible person
• The chain of infection breaks
• Even people who CAN'T be vaccinated (babies, immunocompromised) get protected

1. Occurrence of clinical and subclinical infection in the herd
2. Immunization of the herd
3. Herd structure (births, deaths, migration)

• Virulence of the disease
• Efficacy of the vaccine
• Contact parameter (how infectious the disease is)

Note: In tetanus — herd immunity does NOT protect the individual (because tetanus is not spread person-to-person, it comes from soil)

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COLD CHAIN (Park's PSM)

Park's definition: "The cold chain is a system of storage and transport of vaccines at low temperature from the manufacturer to the actual vaccination site."

1. Right vaccine
2. Right quantity
3. Right place
4. Right time
5. Right condition (no temperature break)
6. Right cost

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NATIONAL IMMUNIZATION PROGRAMME (PSM Focus)

EPI → UIP History:

• 1974: WHO launched EPI (Expanded Programme on Immunization) globally — protect all children against 6 diseases (diphtheria, whooping cough, tetanus, polio, TB, measles) by year 2000
• 1978: EPI launched in India (January 1978)
• 1985 (October): UNICEF launched Universal Child Immunization
• 1985 (November 19): India launched UIP (Universal Immunization Programme) — dedicated to memory of Smt. Indira Gandhi

National Immunization Schedule (NIS) — Key vaccines:

Good Immunization Schedule Criteria (Park's — 4 criteria):

1. Epidemiologically relevant — only against diseases that are public health problems
2. Immunologically effective — vaccinate at right age (before exposure, after maternal antibodies wane)
3. Operationally feasible — minimize visits, achieve high coverage
4. Socially acceptable — consider local customs, beliefs, seasonal factors

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MILESTONES IN VACCINATION (From Park's Table 31)

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🧠 MEMORY TRICKS

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❓ MOST LIKELY EXAM QUESTIONS

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⚡ ONE-PAGE QUICK SUMMARY

VACCINATION = Give the vaccine (physical act)
IMMUNIZATION = Become immune (biological result) ← BROADER TERM

IMMUNIZATION
   ↓
ACTIVE                          PASSIVE
(body makes own antibodies)     (ready-made antibodies given)
• Delayed onset                 • Immediate onset
• Long duration (lifelong)      • Short duration (1–6 weeks)
• Examples: BCG, OPV, DPT       • Examples: ATS, Anti-rabies Ig
• Vaccination achieves this     • Immunoglobulins/antisera

VACCINES:
• Live attenuated → BCG, OPV, MMR, YF, Varicella
• Killed/inactivated → DPT, IPV, Hep A, Typhoid, Cholera
• Toxoids → TT, Diphtheria toxoid
• Recombinant → Hep B, HPV

HERD IMMUNITY = Community protection when enough people are immune
COLD CHAIN = Keep vaccines cold from factory to patient (6 rights)
UIP = Launched India Nov 19, 1985 (EPI launched globally 1974; India 1978)
EPI original 6 diseases = Diphtheria, Whooping cough, Tetanus, Polio, TB, Measles

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