Most effective preventive measure against rabies
In which condition is a night blood survey performed?
Which of the following diseases is not covered under the Integrated Disease Surveillance Project (IDSP)?
Antiserum is available for passive immunization against ?
Which of the following statements best describes the operational definition of onchocerciasis elimination?
Transovarian transmission is seen in-
What is the primary method of primordial prevention for Coronary Artery Disease (CAD)?
What is the BMI classification for an obese person?
In a developing country, the prevalence of diabetes mellitus is increasing at an annual rate of 1.8%. Using epidemiological principles similar to the Rule of 70, approximately how many years will it take for the diabetes prevalence to double, and what are the primary healthcare planning implications of this growth rate?
In the context of demographic studies, how is 'population explosion' defined in terms of growth rate?
NEET-PG 2013 - Community Medicine NEET-PG Practice Questions and MCQs
Question 41: Most effective preventive measure against rabies
- A. Heat
- B. Humidity
- C. Avoiding contact with infected animals and vaccination (Correct Answer)
- D. None of the options
Explanation: ***Avoiding contact with infected animals and vaccination*** ✓ - The most effective preventive measure against rabies is to **avoid contact with potentially infected animals**, especially wild animals and unvaccinated domestic animals. - **Vaccination** (pre-exposure prophylaxis) is crucial for individuals at high risk of exposure (veterinarians, animal handlers, laboratory workers) and for domestic animals, forming the cornerstone of rabies prevention. - Post-exposure prophylaxis (PEP) with immunoglobulin and vaccine series is highly effective when administered promptly after exposure. *Heat* - While high temperatures can inactivate the rabies virus in a laboratory setting, it is **not a practical or effective preventive measure** against rabies in real-world scenarios. - The virus is transmitted through bites, scratches, and mucous membrane contact with infected saliva; environmental heat does not prevent transmission or infection. *Humidity* - **Humidity does not play a significant role** in the prevention or transmission of rabies. - The rabies virus is labile outside of a host and does not survive long in the environment, regardless of humidity levels. *None of the options* - This option is incorrect because there are highly effective preventive measures against rabies, as detailed in the correct option. - Rabies prevention is well-established through public health interventions (animal vaccination programs, post-exposure prophylaxis) and individual precautions.
Question 42: In which condition is a night blood survey performed?
- A. Lymphatic filariasis (Correct Answer)
- B. Typhoid fever
- C. Malaria infection
- D. Visceral leishmaniasis
Explanation: ***Lymphatic filariasis*** - A **night blood survey** is crucial for diagnosing lymphatic filariasis because the microfilariae of species like *Wuchereria bancrofti* and *Brugia malayi* exhibit **nocturnal periodicity**, meaning they are most abundant in peripheral blood between 10 PM and 2 AM. - Collecting blood at night maximizes the chance of detecting these parasites, which are responsible for the disease. *Typhoid fever* - Diagnosis of **typhoid fever** primarily relies on **blood cultures** taken during the febrile phase, or stool/urine cultures later in the disease. - A night blood survey is not relevant for detecting the causative bacterium, *Salmonella Typhi*. *Malaria infection* - While a **blood smear** is essential for diagnosing malaria, the timing of blood collection is less critical than for filariasis, although peak parasite density can vary. - **Malaria parasites** are typically detected in blood samples taken during symptomatic periods, regardless of specific time of day. *Visceral leishmaniasis* - **Visceral leishmaniasis** is diagnosed by detecting parasites in samples from **bone marrow**, spleen, or lymph nodes, or through serological tests for antibodies. - A night blood survey is not used in the diagnosis of *Leishmania donovani* infection.
Question 43: Which of the following diseases is not covered under the Integrated Disease Surveillance Project (IDSP)?
- A. Tuberculosis
- B. Cholera
- C. Herpes zoster (Correct Answer)
- D. Meningococcal disease
Explanation: ***Herpes zoster*** - **Herpes zoster** (shingles) is not included in the Integrated Disease Surveillance Project (IDSP) as it is neither an epidemic-prone disease nor a notifiable disease under the program. - IDSP focuses on diseases with significant public health impact, epidemic potential, or those requiring immediate public health response. - While herpes zoster can cause morbidity in immunocompromised individuals, it does not pose a widespread public health threat requiring national surveillance. *Tuberculosis* - **Tuberculosis (TB)** is explicitly covered under IDSP as a major notifiable disease due to its high burden in India and significant public health importance. - TB surveillance under IDSP helps monitor disease trends, detect outbreaks, and evaluate the effectiveness of the National Tuberculosis Elimination Programme. - Regular reporting and surveillance are essential for achieving TB elimination goals. *Cholera* - **Cholera** is a priority disease under IDSP as an epidemic-prone disease with potential for rapid outbreaks and high mortality if untreated. - It is part of the core surveillance list due to its ability to cause severe dehydration and waterborne epidemics. - Early detection through IDSP enables timely implementation of control measures including safe water supply and oral rehydration therapy. *Meningococcal disease* - **Meningococcal disease** (acute bacterial meningitis) is covered under IDSP due to its high case fatality rate, epidemic potential, and need for urgent public health response. - Surveillance is critical for early outbreak detection and implementation of preventive measures such as mass vaccination and chemoprophylaxis. - Close monitoring helps identify circulating serotypes and guide vaccination strategies.
Question 44: Antiserum is available for passive immunization against ?
- A. Rabies (Correct Answer)
- B. Typhoid
- C. Mumps
- D. Measles
Explanation: ***Rabies*** - **Antiserum** (or rabies immune globulin, RIG) provides immediate **passive immunity** against rabies, neutralizing the virus before the body can mount an active immune response. - It is administered in conjunction with the **rabies vaccine** for post-exposure prophylaxis, especially in severe exposures. *Typhoid* - **Typhoid fever** is primarily prevented through vaccination (active immunization) and improved sanitation. - There is no routinely available antiserum for **passive immunization** against *Salmonella typhi* infection. *Measles* - **Measles** is prevented through active immunization with the MMR (measles, mumps, rubella) vaccine. - While immune globulin can be used for passive protection in exposed, immunocompromised individuals, it's not commonly referred to as "antiserum" in the same context as rabies. *Mumps* - **Mumps** is prevented by active immunization with the MMR vaccine. - Similar to measles, there is no commonly used specific antiserum for **passive immunity** against mumps in the clinical setting.
Question 45: Which of the following statements best describes the operational definition of onchocerciasis elimination?
- A. All interventions have been successfully implemented.
- B. There is no recrudescence of the disease after a defined period.
- C. All of the options are true.
- D. Transmission of O. volvulus has been reduced to a level where it cannot sustain itself in the population. (Correct Answer)
Explanation: **Transmission of O. volvulus has been reduced to a level where it cannot sustain itself in the population.** - This statement accurately reflects the definition of **disease elimination**, where the incidence of infection is reduced to zero in a defined geographical area, signifying that the **transmission cycle can no longer be sustained**. - For onchocerciasis, this means the **vector (blackfly)** is no longer transmitting the parasite (*Onchocerca volvulus*) between humans at a rate that allows the disease to persist. *All interventions have been successfully implemented.* - While successful implementation of interventions is crucial for elimination, it is a **process goal**, not the **ultimate outcome** or operational definition of elimination itself. - Elimination is defined by the **absence of sustained transmission**, which is a direct measure of disease burden, not intervention fidelity. *There is no recrudescence of the disease after a defined period.* - The **absence of recrudescence** (re-emergence) after a defined period is an important indicator of successful elimination validation, but it is a **consequence** or **part of the verification process**, not the primary operational definition. - The operational definition focuses on the **state of transmission** that leads to this sustained absence. *All of the options are true.* - This option is incorrect because only one of the provided statements accurately describes the **operational definition of elimination** in the context of parasitic diseases like onchocerciasis. - The other options describe aspects related to the elimination process or its verification, but not the core definition.
Question 46: Transovarian transmission is seen in-
- A. Malaria
- B. Filaria
- C. Rickettsial diseases (Correct Answer)
- D. None of the options
Explanation: ***Rickettsial diseases*** - **Transovarian transmission** is a key mechanism for the maintenance and spread of **rickettsiae** in arthropod vectors. The bacteria can pass from an infected female arthropod (like a tick or mite) to her offspring via the eggs. - This ensures that the next generation of vectors is already infected and can transmit the disease, even without needing to acquire the pathogen from an infected vertebrate host. *Malaria* - Malaria is transmitted via the bite of an infected **Anopheles mosquito**, which acquires parasites from an infected human. - **Transovarian transmission** does not occur in malaria; mosquitoes are not born with the ability to transmit the parasite. *Filaria* - Filariasis is spread by various **mosquito vectors** (e.g., *Culex*, *Anopheles*, *Aedes*) or **black flies**, which acquire microfilariae from an infected host during a blood meal. - The parasite undergoes development within the insect, but **transovarian transmission** to the insect's offspring does not occur. *None of the options* - This option is incorrect because **rickettsial diseases** do exhibit transovarian transmission, making it a valid answer. - The phenomenon of passing pathogens directly from a female parent to her offspring via the egg is a specific mechanism seen in certain vector-borne diseases.
Question 47: What is the primary method of primordial prevention for Coronary Artery Disease (CAD)?
- A. Lifestyle change (Correct Answer)
- B. Coronary bypass
- C. Treatment of CAD
- D. Screening for hypertension
Explanation: ***Lifestyle change*** - **Primordial prevention** aims to prevent the development of risk factors themselves, which is best achieved through promoting healthy behaviors like diet, exercise, and avoiding tobacco at the population level. - This approach acts *before* the onset of risk factors, addressing societal and environmental determinants of health. - Examples include promoting healthy eating habits in schools, creating walkable communities, and tobacco-free environments. *Coronary bypass* - **Coronary bypass surgery** is a treatment for established CAD with significant blockages, not a preventive measure. - It falls under the category of **tertiary prevention**, aiming to reduce complications and improve quality of life in existing disease. *Treatment of CAD* - **Treating CAD** (e.g., medications like statins or antiplatelets, procedures like angioplasty) is a form of **secondary** or **tertiary prevention**. - It focuses on managing existing disease or preventing its progression, rather than preventing the initial development of risk factors. *Screening for hypertension* - **Screening** is a form of **secondary prevention** aimed at early detection of risk factors or disease. - While important, it occurs *after* risk factors have already developed, unlike primordial prevention which prevents risk factors from emerging.
Question 48: What is the BMI classification for an obese person?
- A. Less than 18.5
- B. 18.5-24.9
- C. 25-29.9
- D. ≥30 (Correct Answer)
Explanation: ***≥30*** - A **Body Mass Index (BMI)** of **30 kg/m² or higher** is the standard WHO classification for **obesity**. - This classification indicates a significant accumulation of body fat that poses increased health risks including cardiovascular disease, type 2 diabetes, and certain cancers. *Less than 18.5* - A BMI in this range indicates that an individual is **underweight**, which also carries potential health risks associated with insufficient body mass. - This is the opposite end of the spectrum from obesity. *18.5-24.9* - This range represents a **healthy weight** or **normal BMI**, indicating a balanced proportion of weight to height. - Individuals in this category generally have the lowest health risks associated with body weight. *25-29.9* - A BMI within this range indicates **overweight**, which is a precursor to obesity if lifestyle changes are not made. - While not categorized as obese, it still carries increased health risks compared to a normal BMI.
Question 49: In a developing country, the prevalence of diabetes mellitus is increasing at an annual rate of 1.8%. Using epidemiological principles similar to the Rule of 70, approximately how many years will it take for the diabetes prevalence to double, and what are the primary healthcare planning implications of this growth rate?
- A. 30-35 years
- B. 35-46 years (Correct Answer)
- C. 25-30 years
- D. 20-25 years
Explanation: ***35-46 years*** - Using the **Rule of 70**, divide 70 by the annual growth rate (1.8%): 70 / 1.8 ≈ **38.89 years**. This value falls within the 35-46 year range. - The doubling of diabetes prevalence within this timeframe necessitates significant **healthcare planning implications**, including increased demand for diagnostic services, medications, and specialized care, as well as focused preventative measures. *30-35 years* - This range is too low, as the calculated doubling time of approximately **38.89 years** is longer than this range. While close, this timeframe underestimates the actual time needed for prevalence to double. *25-30 years* - This range is significantly lower than the calculated doubling time of approximately **38.89 years**, meaning it underestimates the time required for diabetes prevalence to double by about 9-14 years. *20-25 years* - This range is far too low, as the calculated doubling time of approximately **38.89 years** is much longer. This timeframe would suggest a much higher annual growth rate than the stated 1.8%.
Question 50: In the context of demographic studies, how is 'population explosion' defined in terms of growth rate?
- A. > 2% (Correct Answer)
- B. 0.5% - 1.0%
- C. 1.5% - 2.0%
- D. 1.0% - 1.5%
Explanation: ***> 2%*** - A **population explosion** is generally defined as a rapid and significant increase in population size, typically characterized by an annual growth rate exceeding **2%**. - This rate indicates a **doubling time** of approximately 35 years or less, leading to substantial demographic changes. - In the context of Indian demographics, this definition is particularly relevant to the period of rapid population growth experienced in the mid-20th century. *0.5% - 1.0%* - A growth rate in this range is considered **moderate** or even **low** for many developing countries and would not be indicative of a "population explosion." - This rate represents a relatively **stable** or slowly increasing population, not the rapid surge implied by the term. *1.5% - 2.0%* - While a 1.5% to 2.0% growth rate is significant, it often falls short of the threshold typically associated with a "population explosion," which implies a more **accelerated** and **unsustainable** rate of increase. - Many countries with this growth rate face challenges, but it's generally not classified as an "explosion" unless other contextual factors are extreme. *1.0% - 1.5%* - A growth rate between 1.0% and 1.5% is considered a **moderate** rate of population increase. - This range does not signify the rapid and often unmanageable growth implied by the term **population explosion**.