What is the most common method of family planning sterilization practiced in India?
According to WHO guidelines, what prevalence of Bitot's spots indicates a public health problem?
Which of the following best describes the concept where a suspected cause precedes the observed effect?
Who made the statement 'The secret of national health lies in the homes of people'?
Which disease is most closely associated with intensive international surveillance for global eradication?
What is the minimum percentage of the population that needs to be vaccinated to eradicate measles?
In the context of epidemiology, what is the denominator used for calculating incidence?
Secondary prevention is applicable to
Measles vaccination is given at -
Which disease is associated with a propagative cycle?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 11: What is the most common method of family planning sterilization practiced in India?
- A. Female sterilization (Correct Answer)
- B. Male sterilization
- C. Intrauterine device (IUD)
- D. Condom use
Explanation: ***Female sterilization*** - **Female sterilization** (tubal ligation) is the most prevalent method of permanent contraception in India, accounting for over **95% of all sterilization procedures**. - This is primarily due to historical policies focusing on female methods and various **socio-cultural factors** including gender norms and male reluctance. - According to **NFHS data**, female sterilization is the single most common contraceptive method overall in India. *Male sterilization* - **Male sterilization** (vasectomy) is significantly less common compared to female sterilization in India, accounting for less than 5% of sterilization procedures. - This disparity is attributed to **gender norms**, misconceptions about masculinity, and limited promotion of vasectomy services. *Condom use* - While condoms are a common **temporary contraceptive method**, the question specifically asks about **sterilization methods**, which are permanent. - Condoms are barrier methods, not sterilization procedures. *Intrauterine device (IUD)* - IUDs are **reversible long-acting contraceptive methods**, not sterilization procedures. - Though IUDs are increasingly popular in India, they do not constitute a sterilization method as they can be removed.
Question 12: According to WHO guidelines, what prevalence of Bitot's spots indicates a public health problem?
- A. > 1% prevalence
- B. > 2% prevalence
- C. None of the options
- D. ≥ 0.5% prevalence (Correct Answer)
Explanation: ***≥ 0.5% prevalence*** - According to **WHO guidelines**, a prevalence of Bitot's spots of **≥ 0.5%** (greater than or equal to 0.5%) in children aged 6-71 months indicates a **moderate public health problem** related to **vitamin A deficiency**. - This threshold is used for **programmatic decision-making** and intervention strategies to combat **xerophthalmia** (vitamin A deficiency eye disease). - At **≥ 1.0%** prevalence, it indicates a **severe public health problem**. *> 1% prevalence* - While ≥ 1% prevalence indicates a **severe public health problem**, the **initial WHO threshold** for identifying a public health problem due to **vitamin A deficiency** as indicated by Bitot's spots is **≥ 0.5%**. - This allows for **earlier public health action** before the situation becomes severe. *> 2% prevalence* - A prevalence of 2% implies a **critical vitamin A deficiency situation**, far exceeding the **WHO's diagnostic threshold** for initiating public health interventions. - Interventions would be critically urgent at this level, but the criteria for recognizing a problem are met at **≥ 0.5%**. *None of the options* - This option is incorrect because the **WHO has specific guidelines** for the prevalence of **Bitot's spots** that indicate a public health problem. - The correct threshold of **≥ 0.5%** is provided among the choices, which is the established criterion for a **moderate public health problem**.
Question 13: Which of the following best describes the concept where a suspected cause precedes the observed effect?
- A. Temporal association (Correct Answer)
- B. Consistency of association
- C. Strength of association
- D. Coherence of association
Explanation: ***Temporal association*** - This principle in **causal inference** emphasizes that for a factor to be a cause, it must precede the effect. - In epidemiology, it's crucial to establish that exposure occurred **before the disease manifestation**. *Consistency of association* - Refers to the observation of a **similar association across different studies** and populations. - While important for causal inference, it does not directly address the timing of cause and effect. *Strength of association* - Quantifies how often the **exposure and outcome co-occur**, often measured by relative risk or odds ratio. - A strong association is more likely to be causal, but it doesn't confirm that the cause came before the effect. *Coherence of association* - Implies that the observed association should be **consistent with existing biological and medical knowledge**. - This criterion supports the plausibility of an association but doesn't specifically deal with the temporal sequence.
Question 14: Who made the statement 'The secret of national health lies in the homes of people'?
- A. Indira Gandhi
- B. Florence Nightingale
- C. Bhore (Correct Answer)
- D. Abraham Lincoln
Explanation: ***Bhore (Bhore Committee Report, 1946)*** - This famous statement emphasizes the importance of **community-level health** and the role of individuals and families in maintaining national health. - The **Bhore Committee**, chaired by Sir Joseph Bhore in colonial India (1943-1946), was a landmark Health Survey and Development Committee that laid the foundation for India's health policy. - The committee highlighted the need for **primary healthcare at the grassroots level**, accessibility of health services, and the integration of preventive and curative services. - This philosophy remains foundational to India's public health approach and community medicine. *Indira Gandhi* - While a prominent Prime Minister of India who contributed significantly to national development programs and social welfare initiatives, this specific statement is not attributed to her. - Her health-related contributions included the **National Health Policy** discussions and family planning programs, but this quote predates her political leadership. *Abraham Lincoln* - As the 16th U.S. President (1861-1865), his leadership focused on the Civil War and abolition of slavery. - His famous speeches include the Gettysburg Address with "**government of the people, by the people, for the people**" but do not address national health in this specific manner. *Florence Nightingale* - A pioneer of modern nursing and founder of professional nursing education, she emphasized **sanitation**, hygiene, and patient care. - While she revolutionized hospital conditions and public health nursing, particularly during the Crimean War (1853-1856), this exact quote is not attributed to her. - Her focus was on **evidence-based nursing practice** and improving hospital sanitation standards.
Question 15: Which disease is most closely associated with intensive international surveillance for global eradication?
- A. Polio (Correct Answer)
- B. Hepatitis
- C. TB
- D. Leprosy
Explanation: **Polio** - **Polio** has been the focus of an intensive global eradication campaign, requiring robust **international surveillance** to track cases, mutations, and vaccine-derived polioviruses. - The **Global Polio Eradication Initiative (GPEI)**, a major international collaboration, relies heavily on coordinated surveillance efforts to ensure no wild poliovirus remains undetected. *Hepatitis* - While **hepatitis** is a significant global health burden, particularly hepatitis B and C, it is not subject to the same level of internationally coordinated, aggressive surveillance aimed at **global eradication** as polio. - Surveillance for hepatitis often focuses on prevalence, incidence, and risk factors at national and regional levels rather than a centralized, real-time eradication tracking system. *TB* - **Tuberculosis (TB)** is a major global health concern, and there are international efforts for control and elimination, but it is not currently targeted for **global eradication** in the same manner as polio. - Surveillance for TB often involves tracking drug-resistant strains and treatment outcomes, but it doesn't involve the immediate, outbreak-focused international alert system seen with diseases like polio or novel pandemics. *Leprosy* - **Leprosy** is a neglected tropical disease, and while there are international efforts for its control and elimination, primarily led by the WHO, it does not involve the same level of intensive, real-time global surveillance for eradication as **polio**. - Surveillance for leprosy is typically focused on case detection, treatment completion, and identifying areas with high endemicity rather than rapid international notification of individual cases for eradication purposes.
Question 16: What is the minimum percentage of the population that needs to be vaccinated to eradicate measles?
- A. 85%
- B. 95% (Correct Answer)
- C. 70%
- D. 80%
Explanation: **95%** - Measles is highly contagious, requiring a **high percentage of immunity** in the population to establish **herd immunity** and prevent outbreaks. - A **95% vaccination coverage** ensures that enough individuals are protected, breaking the chain of transmission and leading to potential eradication. *85%* - This percentage is **insufficient** for highly transmissible diseases like measles. - An 85% vaccination rate would still leave a significant portion of the population susceptible, allowing measles to **continue circulating** and causing outbreaks. *70%* - This level of vaccination is **far too low** for measles, which has a basic reproduction number (R0) of 12-18. - A 70% coverage would result in frequent and widespread measles outbreaks due to **inadequate herd immunity**. *80%* - While 80% vaccination offers some protection, it is still **below the threshold** needed for measles eradication. - Measles outbreaks can still occur with an 80% coverage, particularly in populations with **non-uniform distribution of immunity**.
Question 17: In the context of epidemiology, what is the denominator used for calculating incidence?
- A. Mid year population
- B. Population at risk (Correct Answer)
- C. Total number of cases
- D. Total number of deaths
Explanation: ***Population at risk*** - Incidence measures the **rate of new cases** of a disease in a population over a specified period. - The denominator for calculating incidence must exclude individuals who are **already diseased** or are **immune** and thus not susceptible to developing the condition. - This is the **most accurate and theoretically correct** denominator as it represents only those who can actually develop the disease. *Mid year population* - While often used as a **practical approximation** in epidemiological calculations when the exact population at risk is difficult to determine. - However, it includes individuals who may not be at risk (e.g., already have the disease or are immune), making it **less precise** than using the actual susceptible population. - For the **theoretical definition** of incidence rate, population at risk is the correct denominator. *Total number of cases* - This value represents the **numerator** for incidence calculations, as it counts the number of new events or diseases occurring. - It cannot serve as the denominator, as the denominator must reflect the pool of individuals from which these **new cases arose**. *Total number of deaths* - This is a measure of **mortality**, not incidence, and is used to calculate death rates. - The denominator for mortality rates is typically the **population at risk of death**, not specifically the population at risk of developing a disease.
Question 18: Secondary prevention is applicable to
- A. Early stage of disease (Correct Answer)
- B. Factors leading to disease
- C. Advanced stage of disease
- D. None of the options
Explanation: ***Early stage of disease*** - **Secondary prevention** focuses on early detection and prompt treatment to halt the progression of an existing disease. - This stage is crucial for interventions like **screening tests** and **early diagnosis**, which aim to minimize the impact of the disease once it has begun. *Factors leading to disease* - This relates to **primary prevention**, which aims to prevent the disease from occurring in the first place by addressing risk factors or promoting health. - Examples include **vaccination** or promoting healthy lifestyle choices. *Advanced stage of disease* - This is the domain of **tertiary prevention**, which focuses on managing the disease, preventing complications, and improving quality of life once the disease is well-established. - Rehabilitation and long-term care are key aspects of this stage. *None of the options* - This option is incorrect because secondary prevention specifically targets the **early stage of disease** to prevent further progression and adverse outcomes.
Question 19: Measles vaccination is given at -
- A. 9 months (Correct Answer)
- B. At birth
- C. 4 weeks
- D. 8 weeks
Explanation: ***9 months*** - The first dose of the **measles vaccine (MMR)** is typically administered at **9 months** of age in many national immunization programs. - This timing is chosen because maternal antibodies, which can interfere with vaccine effectiveness, generally wane by this age. *At birth* - Vaccines given at birth, such as **Hepatitis B** and **BCG**, target diseases with early exposure risks or have efficacy despite maternal antibodies. - Giving measles vaccine at birth would be ineffective due to the presence of **maternal antibodies** that neutralize the vaccine virus. *4 weeks* - This age is generally too early for measles vaccination as significant levels of **maternal antibodies** are often still present, which would reduce the vaccine's efficacy. - Other vaccines, like the rotavirus vaccine, might be given around this age, but not measles. *8 weeks* - While maternal antibodies might be decreasing, 8 weeks of age is still generally considered too early for optimal measles vaccine response. - Many primary vaccine series (e.g., DTaP, IPV, Hib) begin at 6-8 weeks, but measles is usually delayed further for better efficacy and seroconversion rates.
Question 20: Which disease is associated with a propagative cycle?
- A. None of the options
- B. Plague
- C. Filaria (Correct Answer)
- D. Malaria
Explanation: ***Filaria*** - The **filarial worm** undergoes a **biological transmission cycle** in the mosquito vector where microfilariae develop through larval stages (L1 → L2 → L3) with multiplication. - This represents a **cyclopropagative cycle** (both development and multiplication occur in the vector). - In the context of this question and classical teaching, filaria is considered the standard example of biological transmission with vector multiplication. - The infective L3 larvae multiply from a single microfilaria, and multiple larvae can develop within one mosquito. *Plague* - **Plague** (*Yersinia pestis*) is transmitted by fleas through **mechanical transmission**. - Bacteria multiply in the flea's gut causing blockage (blocking transmission), but this is not considered a true biological cycle. - The pathogen does not undergo developmental stages in the vector. *Malaria* - **Malaria** (*Plasmodium* spp.) undergoes the **sporogonic cycle** in the mosquito, which is also a **cyclopropagative cycle**. - Gametocytes → ookinete → oocyst → sporozoites (development with multiplication). - While biologically similar to filaria, in classical epidemiology teaching, filaria is more commonly cited as the example for propagative transmission. *None of the options* - This option is incorrect as filaria demonstrates biological transmission with multiplication in the vector. - Both filaria and malaria technically undergo cyclopropagative cycles, but filaria is the conventional answer in medical education contexts.