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Community Medicine - 8 Mark Answers (K. Park)

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60. COLD CHAIN - System, Equipment, Open Vial Policy, Reverse Cold Chain

• Vaccines are sensitive biological products - some to heat, some to freezing, some to light
• Once potency is lost, it cannot be regained
• Most vaccines: +2°C to +8°C
• Vaccines sensitive to freezing: Cholera, DTaP, Hep B, HPV, IPV, Influenza, Pneumococcal, Td, TT

1. Electrical equipment - Ice-lined refrigerators (ILR), deep freezers, refrigerators
2. Solar cold chain equipment - Solar refrigerators/freezers used in areas without reliable electricity
3. Non-electrical equipment - Cold boxes, vaccine carriers, ice packs

• Multi-dose vials of certain vaccines (OPV, measles, Hep B, DPT, TT) that have been opened may be used in subsequent sessions if: the expiry date has not passed, vaccines are stored under appropriate cold chain conditions, vaccine vial monitor (VVM) has not reached discard point, and there is no visible contamination.
• Vaccines NOT covered under OVP: Vaccines requiring reconstitution (BCG, measles, yellow fever) - must be discarded within 6 hours or at end of session.

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61. FOOD FORTIFICATION, ADULTERATION, PFA ACT

• Enacted to protect consumers from adulterated and misbranded food
• Defines standards for food articles
• Provides for appointment of food inspectors and public analysts
• Penalties for violation
• Later supplemented by the Food Safety and Standards Act (FSSAI), 2006

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62. SOCIAL MARKETING

1. Product - The desired behaviour or health practice (e.g., condom use, ORS use)
2. Price - Cost (monetary and psychological) to the consumer
3. Place - Accessibility and distribution channels
4. Promotion - Communication and persuasion strategies

• Uses consumer-oriented research to understand the target population
• Segments the population for tailored messages
• Employs commercial media and distribution channels
• Focuses on voluntary behaviour change
• Continuous monitoring and evaluation

• Condom social marketing (family planning)
• ORS sachets distribution
• Bed net promotion (malaria)
• Iodized salt promotion

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63. TYPES OF REHABILITATION

1. Medical Rehabilitation - Restoration of function through medical and surgical care, physiotherapy, occupational therapy
2. Vocational Rehabilitation - Training and retraining for suitable employment; helps disabled person earn a living
3. Social Rehabilitation - Restoring family and social relationships; adjusting the individual to community life
4. Psychological Rehabilitation - Addressing mental health, motivation, and behavioral aspects of disability

• Defined by WHO as "a strategy within general community development for the rehabilitation, equalization of opportunities and social inclusion of all people with disabilities"
• Implemented through combined efforts of disabled people themselves, their families, organizations, and communities
• Advantages: Reaches more people, less costly, uses local resources, better community acceptance
• India has launched the District Rehabilitation Centre (DRC) scheme under CBR

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64. DIETARY FIBRE

• Increases fecal bulk and reduces transit time
• Reduces intracolonic pressure
• Binds bile acids and reduces serum cholesterol
• Slows glucose absorption - beneficial in diabetes
• Produces short-chain fatty acids in colon

1. Prevention of constipation
2. Reduces risk of colorectal cancer
3. Lowers serum cholesterol - prevents coronary heart disease
4. Improves glycemic control in diabetes
5. Reduces risk of diverticular disease
6. Assists in weight management (increases satiety)

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65. LATHYRISM (Neurolathyrism)

1. Latent stage - Subclinical; no overt symptoms
2. Trembling stage (Prodromal) - Weakness, trembling of legs
3. Stage of paraplegia - Spastic paraplegia of lower limbs; "scissors gait"

• Limit lathyrus to <30% of total diet; preferably ban its sale
• Detoxification: Soak in hot water and discard the water (removes water-soluble BOAA)
• Nutritional diversification
• Agricultural substitution with safer crops

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66. OCCUPATIONAL HAZARDS AND HAZARDS OF AGRICULTURAL WORKERS

• Heat - Burns, heat exhaustion, heat stroke, heat cramps; increased accident rate
• Cold - Chilblains, erythrocyanosis, immersion foot, frostbite
• Light - Poor illumination: eye strain, "miner's nystagmus"; glare: visual fatigue
• Noise - Auditory: temporary/permanent hearing loss; Non-auditory: fatigue, decreased efficiency
• Radiation - Ionizing and non-ionizing radiation effects
• Atmospheric pressure - Decompression sickness (caisson disease)
• Vibration - Vibration white finger (Raynaud's phenomenon)

• Pesticide poisoning (organophosphates, carbamates)
• Heat exhaustion
• Skin diseases (contact dermatitis)
• Respiratory diseases (farmers' lung - due to mouldy hay)
• Tetanus, leptospirosis, hookworm
• Zoonoses (anthrax, brucellosis)
• Musculoskeletal problems

• Helmets, gloves, masks, goggles, ear plugs, protective clothing, safety shoes

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67. ANTI-RODENT MEASURES AND RODENT-BORNE DISEASES

• Plague (Yersinia pestis, via rat flea Xenopsylla cheopis)
• Murine typhus (Rickettsia typhi)
• Leptospirosis (direct contact with rat urine)
• Rat bite fever (Spirillum minus, Streptobacillus moniliformis)
• Scrub typhus
• Hantavirus infections
• Salmonellosis (contaminated food)

• Rodent proofing of buildings (sealing holes, use of metal)
• Proper garbage disposal and sanitation
• Elimination of harborages (woodpiles, rubbish)
• Proper food storage
• Rat-proofing of drains and sewers

• Anticoagulants (preferred): Warfarin, coumatetralyl - multiple feeding required; rats do not develop bait shyness
• Acute poisons: Zinc phosphide (single dose, bait shyness develops)
• Brodifacoum, bromadiolone (second generation anticoagulants)

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68. TOOLS OF EPIDEMIOLOGY

• Incidence rate, prevalence rate, attack rate, mortality rate, CFR, etc.

• Descriptive studies (case reports, cross-sectional surveys)
• Analytical studies (case-control, cohort)
• Experimental studies (RCT, field trials, community trials)

• Mass screening, selective screening, multiphasic screening

• Passive, active, sentinel surveillance; epidemiological intelligence

• Verify diagnosis, confirm epidemic, describe by time/place/person, formulate hypothesis, test hypothesis, control measures

• Measures of central tendency, dispersion, tests of significance (chi-square, t-test)

• GIS mapping, disease registries, health information systems

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69. FATHER OF INDIAN SURGERY - CONTRIBUTION

• Wrote Sushruta Samhita (600 BC) - a comprehensive surgical treatise
• Described 300 surgical procedures and 120 surgical instruments
• Pioneer of rhinoplasty (reconstruction of nose) - technique later adopted by Europeans
• Described cataract couching
• Classified surgical operations into 8 types (Ashtavidha karma)
• Described anatomy, pathology, and wound healing
• Emphasized aseptic techniques (fumigation, wound cleaning)
• Recognized importance of surgical training on inanimate objects before operating on humans

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70. ACCIDENTS IN INDUSTRY AND PRE-PLACEMENT MEDICAL EXAMINATION

1. Host (Worker) - Age, sex, intelligence, skill, fatigue, alcohol, emotional state
2. Agent (Hazardous environment) - Machinery, chemicals, heights, electrical hazards
3. Environment - Poor lighting, noise, inadequate space, weather

• Engineering controls (guarding machinery)
• Safe work procedures
• Personal protective equipment
• Health education and training
• Adequate lighting and ventilation
• Enforcement of Factories Act

1. Detect pre-existing diseases that may be aggravated by specific work
2. Identify conditions that may render a worker unsuitable for certain jobs
3. Establish a baseline health record
4. Ensure the worker is fit for the demands of the job
5. Detect communicable diseases (e.g., TB) that could be transmitted to co-workers
6. Includes: complete medical history, physical examination, vision/hearing tests, chest X-ray, blood and urine tests, and specific tests based on the nature of work

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71. CLASSIFICATION OF EPIDEMIOLOGICAL STUDIES AND TYPES OF EPIDEMICS / SECULAR TREND

1. Descriptive Studies:
   • Case reports/series
   • Cross-sectional (prevalence) studies
   • Ecological (correlational) studies
2. Analytical Studies:
   • Case-control studies (retrospective)
   • Cohort studies (prospective/retrospective)

1. Randomized Controlled Trials (RCT)
2. Field trials
3. Community intervention trials

1. Common Source Epidemic:
   • Point source - All exposed to the same source at one time; sharp rise then rapid fall; incubation period can be deduced. E.g., food poisoning outbreak
   • Continuous/Propagated source - Continued exposure over time; plateau-shaped curve. E.g., waterborne typhoid
   • Intermittent source - Interrupted exposure; series of peaks
2. Propagated (Person-to-Person) Epidemic:
   • Spread from person to person; gradual rise; curve has multiple peaks at successive incubation periods; e.g., measles, chickenpox
3. Mixed Epidemic: Initial common source followed by person-to-person spread (e.g., Hepatitis A)

• Changes in the frequency of a disease over a long period of time (decades to centuries)
• Reflects changes in herd immunity, virulence, living standards, medical care
• Example: Declining trend of TB mortality in England over 150 years before BCG or antibiotics were introduced - attributed to improved living conditions

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72. SCREENING TEST - VALIDITY, CRITERIA, TYPES, USES, EVALUATION

1. Acceptability - Acceptable to the target population
2. Repeatability (Reliability) - Consistent results on repeated application
3. Validity - Ability to measure what it purports to measure
   • Sensitivity - Ability to correctly identify diseased persons (true positives)
   • Specificity - Ability to correctly identify non-diseased persons (true negatives)

• Sensitivity = TP/(TP+FN) × 100
• Specificity = TN/(TN+FP) × 100
• Predictive Value Positive = TP/(TP+FP) × 100
• Predictive Value Negative = TN/(TN+FN) × 100

1. Mass screening - Entire population
2. Selective (High-risk) screening - Target high-risk groups
3. Multiphasic screening - Several tests applied simultaneously
4. Case-finding (Opportunistic) - During routine clinical contact

• Early detection of disease
• Reduction of morbidity and mortality
• Identify high-risk groups
• Study natural history of disease
• Cost-effective use of health resources

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73. COMMUNITY NUTRITION PROGRAMMES IN INDIA AND ICDS

• Launched: 1975 (October 2)
• Target beneficiaries: Children 0-6 years, pregnant women, nursing mothers, adolescent girls
• Implemented through Anganwadi centres

1. Supplementary nutrition
2. Immunization
3. Health check-up
4. Referral services
5. Non-formal pre-school education
6. Nutrition and health education

• Improve nutritional and health status of children under 6
• Lay foundation for proper psychological, physical, and social development of the child
• Reduce mortality, morbidity, malnutrition, and school dropout
• Achieve effective coordination of policy and implementation

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74. PRENATAL DIAGNOSIS

1. Maternal age >35 years (risk of Down syndrome)
2. Previous child with chromosomal abnormality
3. Family history of genetic disorders
4. Consanguineous marriages
5. Carrier status for X-linked disorders (mother)
6. Balanced translocation in parent

1. Ultrasonography - Detects structural abnormalities, fetal age
2. Maternal serum screening - AFP, beta-hCG, estriol (Triple test); PAPP-A (Double marker)
3. Fetal imaging (MRI)

1. Amniocentesis (15-18 weeks) - Amniotic fluid; chromosomal karyotyping, biochemical analysis
2. Chorionic Villus Sampling (CVS) (10-12 weeks) - Earlier result; risk of miscarriage ~1%
3. Cordocentesis/PUBS - Fetal blood sampling from umbilical cord; rapid karyotyping
4. Fetoscopy - Direct visualization of fetus

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75. GROUP DISCUSSION (Health Communication Method)

• Group size: 8-15 persons (ideal)
• Duration: 45-90 minutes
• Requires a skilled leader/moderator
• All members actively participate
• No formal presentation; conversational

1. Group discussion
2. Panel discussion - 4-8 experts discuss before an audience
3. Symposium - Series of prepared speeches by experts
4. Workshop - Small groups work on specific problems
5. Conference/Seminar
6. Role play

• Active participation of all members
• Encourages sharing of experiences and peer learning
• Effective for attitude and behaviour change
• Allows questions, doubts and fears to be expressed
• More influence on below-average educational level groups
• Suitable for sensitive topics (family planning, STD)

• Time-consuming
• Requires skilled leader
• Not suitable for large groups
• Dominant members may control discussion

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76. HEALTH TEAM CONCEPT

• The modern physician is overworked and many functions can be performed by trained auxiliaries
• An auxiliary is "one who has less than full professional qualifications in a particular field and is supervised by a professional worker"

• Medical: Physicians, specialists
• Nursing: Nurses, midwives, ANMs
• Technical: Lab technicians, pharmacists, radiographers
• Social: Medical social workers, health educators
• Field workers: ASHAs, MPWs, health assistants
• Community members themselves

1. Each member has specific and recognized function
2. Division of labour with complementary skills
3. The team requires a leader
4. Co-ordination and mutual respect among members
5. Common goal - health of the community

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77. ICEBERG PHENOMENON OF DISEASE

• In many diseases (hypertension, diabetes, anaemia, malnutrition, mental illness), the hidden (submerged) morbidity far exceeds known morbidity
• The hidden portion constitutes an important, undiagnosed reservoir of infection or disease
• Detection and control of the "below waterline" cases is a major challenge in preventive medicine
• Absence of methods to detect the subclinical state is a major deterrent in chronic disease study

• Poliomyelitis: 1 clinical case for every 200+ subclinical infections
• Tuberculosis: Large reservoir of infection without clinical disease
• Hypertension: Majority of cases undiagnosed
• Diabetes mellitus: For every known diabetic, 1-2 undiagnosed cases exist
• Mental illness: Only a fraction reaches medical attention

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78. SCREENING vs DIAGNOSTIC TEST

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79. PQLI (PHYSICAL QUALITY OF LIFE INDEX)

1. Infant mortality rate (per 1000 live births)
2. Life expectancy at age one (years)
3. Literacy rate (%)

• Each component is placed on a scale of 0 to 100
  • 0 = absolutely defined "worst" performance
  • 100 = absolutely defined "best" performance
• PQLI = Average of the three indicators (equal weight to each)
• PQLI ranges from 0 to 100
• Ultimate objective: PQLI of 100

• Does NOT consider per capita GNP - shows "money is not everything"
• Oil-rich Middle Eastern countries: High per capita income but not very high PQLI
• Sri Lanka and Kerala state (India): Low per capita income but HIGH PQLI - demonstrating the role of social policies
• PQLI measures results of social, economic and political policies
• Intended to complement, not replace, GNP

• Only 3 indicators - does not capture all dimensions of quality of life
• Replaced in part by the broader Human Development Index (HDI) which includes life expectancy at birth, education (mean + expected years of schooling), and GNI per capita

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80. SENSITIVITY AND SPECIFICITY

• Introduced by Yerushalmy (1940s)
• Defined as "the ability of a test to identify correctly all those who have the disease" - i.e., true positive rate
• 90% sensitivity = 90% of diseased persons test positive; 10% give false-negative results
• Formula: Sensitivity = TP/(TP+FN) × 100

• Defined as "the ability of a test to identify correctly those who do NOT have the disease" - i.e., true negative rate
• 90% specificity = 90% of non-diseased persons test negative; 10% give false-positive results
• Formula: Specificity = TN/(TN+FP) × 100

• Sensitivity and specificity are inversely related
• Increasing sensitivity decreases specificity and vice versa
• An ideal test would be 100% sensitive AND 100% specific - rarely achieved in practice

• Positive Predictive Value (PPV) = TP/(TP+FP) × 100 - probability of having disease if test is positive; depends heavily on prevalence
• Negative Predictive Value (NPV) = TN/(TN+FN) × 100

• 2-hour post-prandial blood glucose ≥180 mg/dl for diabetes: Sensitivity = 50%, Specificity = 99.8%
• CAT scan is both more sensitive and more specific than EEG for brain tumour diagnosis

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81. BREAKPOINT CHLORINATION

• As chlorine dose is increased, residual chlorine initially falls (because chloramine is being destroyed)
• At a certain point, all combined chlorines (chloramines) are completely destroyed
• After this point, residual chlorine begins to increase in proportion to the added chlorine dose
• This critical point is called the BREAKPOINT

• At breakpoint, free residual chlorine is present - which is far more effective as a disinfectant
• Breakpoint chlorination = controlled superchlorination
• Ensures maximum bactericidal efficiency
• Used when water contains high ammonia levels
• Eliminates tastes and odours caused by chloramines

• 0.2 mg/L free residual chlorine for clear water
• 0.5 mg/L for slightly turbid water

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82. CLASSIFICATION OF DUST DISEASES, BYSSINOSIS AND BAGASSOSIS

• Caused by inhalation of cotton fibre dust over long periods
• India has a large textile industry employing ~35% of factory workers
• Incidence: 7-8% (surveys in Mumbai, Ahmedabad, Delhi)
• Features: Chronic cough, progressive dyspnoea; characteristic "Monday fever" (symptoms worse on first day back after weekend)
• Ends in chronic bronchitis and emphysema

• Caused by inhalation of bagasse (sugarcane fibre) dust
• First reported in India by Ganguli and Pal (1955) near Kolkata
• Causative agent: Thermoactinomyces sacchari (thermophilic actinomycete)
• Features: Breathlessness, cough, haemoptysis, slight fever; acute diffuse bronchiolitis; mottling on X-ray
• Complications if untreated: Diffuse fibrosis, emphysema, bronchiectasis
• Prevention: Dust control (wet process, exhaust ventilation), PPE (masks/respirators), medical surveillance, keep moisture content of bagasse >20% and spray with 2% propionic acid

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83. CLASSIFICATION OF HEALTH COMMUNICATION / GROUP AND MASS APPROACH

• Personal contact
• Home visits
• Personal letters

• Lectures (Chalk and talk)
• Demonstrations
• Discussion methods:
  • Group discussion (8-15 persons; active participation)
  • Panel discussion (4-8 experts before audience)
  • Symposium (series of prepared speeches)
  • Workshop
  • Conferences, Seminars
  • Role play

• Television
• Radio
• Newspapers
• Printed material (leaflets, pamphlets)
• Direct mailing
• Posters/billboards
• Health museums and exhibitions
• Folk methods (street plays, puppet shows)
• Internet/social media

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84. GERM THEORY OF DISEASE

• Man long groped in darkness about disease causation
• Early theories: Supernatural theory, Theory of Humors (Greeks/Indians), Miasmatic theory (disease from noxious air), Theory of spontaneous generation

• 1860 - Louis Pasteur (1822-1895) demonstrated bacteria in air and disproved spontaneous generation
• 1873 - Pasteur advanced the Germ Theory of Disease
• 1877 - Robert Koch (1843-1910) showed anthrax was caused by bacteria

• Gonococcus (1847), Typhoid bacillus & Pneumococcus (1880), Tubercle bacillus (1882), Cholera vibrio (1883), Diphtheria bacillus (1884)

1. The organism must be found in all cases of the disease
2. It must be isolated from the diseased host and grown in pure culture
3. The cultured microbe must cause disease when introduced into a healthy experimental host
4. The organism must be reisolated from the experimentally diseased host

• Germ theory brought scientific basis to medicine
• All attention focused on microbes as disease causative agents
• Foundation for development of vaccines, antibiotics, antiseptics
• Led eventually to the more comprehensive Epidemiological Triad (Agent-Host-Environment)

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85. THE SICK ROLE (Parsons)

• He strips off customary identity
• Becomes subject to a schedule not of his own making
• Becomes passive and child-like

1. Exemption from normal social responsibilities - The sick person is exempt from usual roles (work, family duties) depending on severity of illness; this exemption requires validation by a physician
2. The sick person needs to be cared for - He/she is dependent and needs care; cannot recover by will power alone; requires care of others
3. Sick role is regarded as undesirable (a misfortune) - The state of illness is considered undesirable and the individual is obligated to want to get well
4. Obligation to seek competent medical help and cooperate - The sick person is obliged to seek competent medical care and cooperate with the doctor in getting well

• Typical sick role - Temporary; patient wants to recover
• Prolonged sick role - Some patients prefer extended sick role to escape everyday responsibilities (secondary gain)
• Deviant sick role - Person refuses to accept treatment or cooperate
• Hypochondriac - Assumes sick role without biological justification

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86. SCREENING - DEFINITION, USES

1. Early detection of disease - Detect disease in pre-symptomatic or early symptomatic stage when treatment is more effective (e.g., cervical cancer by Pap smear)
2. Reducing morbidity and mortality - Early treatment improves prognosis
3. Identify high-risk groups - For targeted intervention and health education
4. Study natural history of disease - Understanding spectrum of disease from subclinical to clinical
5. Cost-effective public health - Treating early disease is less expensive than treating advanced disease
6. Control of communicable diseases - E.g., pre-employment chest X-ray for TB
7. Evaluation of control programmes - Assess impact of interventions

1. The condition must be important public health problem
2. Accepted treatment must be available
3. Facilities for diagnosis and treatment must be available
4. Recognizable latent or presymptomatic stage must exist
5. Suitable test or examination must exist
6. Test must be acceptable to the population
7. Natural history of disease must be adequately understood
8. Agreed policy on whom to treat
9. Cost must be economically balanced
10. Case-finding must be a continuing process

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87. HARD TICKS vs SOFT TICKS

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88. TYPES OF FAMILY

1. Nuclear Family - Husband, wife, and their unmarried children; most common in urban areas; also called "conjugal family"
2. Joint (Extended) Family - Three or more generations living together; includes grandparents, parents, children, and sometimes other relatives; prevalent in rural India
3. Three-generation Family - Three generations under one roof
4. Single-parent Family - Only one parent (divorced, widowed, unmarried) with children

1. Patriarchal Family - Authority vested in father/oldest male
2. Matriarchal Family - Authority vested in mother/oldest female

1. Patrilineal - Descent traced through father's line
2. Matrilineal - Descent traced through mother's line (e.g., Khasi, Nair)

1. Patrilocal - Couple lives with husband's family
2. Matrilocal - Couple lives with wife's family
3. Neolocal - Couple establishes independent residence

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89. WATER-BORNE DISEASES AND RAPID SAND FILTRATION

1. Cholera
2. Typhoid and Paratyphoid fever
3. Bacillary and Amoebic Dysentery
4. Hepatitis A and E
5. Gastroenteritis (various bacterial, viral, parasitic causes)
6. Poliomyelitis
7. Leptospirosis
8. Dracunculiasis (Guinea worm - now nearly eradicated)
9. Giardiasis, Cryptosporidiosis

• Also called Mechanical filtration or Pressure filtration
• Rate: 5 metres/hour (much faster than slow sand filter which runs at 0.1-0.4 m/hour)
• Requires prior coagulation and sedimentation (alum is added)

1. Raw water → Coagulation (addition of alum/ferric sulphate) → Floc formation
2. → Sedimentation tank (floc settles)
3. → Rapid sand filter (sand bed 60-75 cm; gravel underlayer)
4. → Chlorination → Distribution

• Much faster (handles large volumes)
• Occupies less land
• Easier to manage
• Suitable for large municipal supplies

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90. DEPROFESSIONALISATION OF MEDICINE

1. Rise of the informed patient - Internet, health literacy; patients question medical authority
2. Growth of paramedical professions - Nurses, physiotherapists, nurse practitioners taking over some physician roles
3. Bureaucratization of health care - Doctors employed by governments/hospitals lose autonomy
4. Alternative/complementary medicine - Patients seek non-allopathic care
5. Consumer movement - Patients demand rights, second opinions, involvement in treatment decisions
6. Commercialization - Medicine increasingly seen as a service industry
7. Advances in technology - Diagnostic machines replace clinical judgment

• Shift from paternalistic to partnership model of doctor-patient relationship
• Greater accountability and transparency in medical practice
• Increased patient autonomy
• Challenges to medical ethics and traditional professional values

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91. ISOLATION vs QUARANTINE AND EMPORIATRICS

• Definition: "Separation, for the period of communicability of infected persons or animals from others in such places and under such conditions as to prevent or limit the direct or indirect transmission of the infectious agent." (Last, 2001)
• Applied to: Infected/sick persons (cases and carriers)
• Purpose: Protect community by preventing transfer of infection to susceptible hosts
• Duration: Determined by the period of communicability of the disease

1. Standard isolation - Routine precautions
2. Strict isolation - Highly contagious diseases
3. Protective (Reverse) isolation - Protect immunocompromised host from environment
4. High security isolation - Special pathogens (Ebola, etc.)

• Definition: "Limitation of freedom of movement of such well persons or domestic animals exposed to a communicable disease for a period not longer than the longest usual incubation period of the disease, in such manner as to prevent effective contact with those not so exposed."
• Applied to: Healthy contacts (exposed but not yet ill)
• Types:
  1. Absolute quarantine - Complete restriction for full incubation period
  2. Modified quarantine - Selective partial restriction (e.g., exclusion of children from school)
  3. Segregation - Separation of part of a group for observation

• Isolation → for the SICK (infected)
• Quarantine → for the HEALTHY (exposed/contacts)

• Derived from Greek word "emporos" (traveller/passenger)
• Branch of medicine dealing with health problems of international travellers
• Includes: pre-travel vaccinations, chemoprophylaxis (malaria), food/water safety advice, management of travel-related illness (traveller's diarrhoea, deep vein thrombosis, jet lag), re-entry health assessment
• Important with increase in international travel and risk of importation of exotic diseases

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Source: All answers compiled from K. Park's Textbook of Preventive and Social Medicine (Park's PSM). Each answer is structured for an 8-mark exam response with definition, classification, key points, and clinical/public health significance.