Which is the main vector of Dengue?
Which of the following is a zoonotic disease?
Which of the following statements about the Late Expanding Phase of the Demographic Cycle is TRUE?
What does the net reproduction rate indicate?
What is the purpose of work sampling in industrial engineering?
Child protection scheme is under which ministry?
Secondary prevention is applicable to
Transovarian transmission is seen in which of the following infections?
Which of the following diseases does not have a chronic carrier state?
Which disease is associated with a propagative cycle?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 21: Which is the main vector of Dengue?
- A. A. aegypti (Correct Answer)
- B. Culex
- C. Anopheles
- D. Aedes scutellaris
Explanation: ***A. aegypti*** - **Aedes aegypti** is the primary vector responsible for transmitting the **Dengue virus** to humans. - It is a **day-biting mosquito** found predominantly in tropical and subtropical regions. *Culex* - **Culex mosquitoes** are known vectors for diseases like **Japanese encephalitis**, **West Nile virus**, and **filariasis**. - They are generally **night-biting** and do not play a significant role in Dengue transmission. *Anopheles* - **Anopheles mosquitoes** are the primary vectors for **malaria** in humans. - They are not associated with the transmission of the Dengue virus. *Aedes scutellaris* - While part of the **Aedes genus**, **Aedes scutellaris** is a secondary vector for Dengue in the **Pacific region**. - The main vector for Dengue globally remains **Aedes aegypti**, followed by **Aedes albopictus** in some regions.
Question 22: Which of the following is a zoonotic disease?
- A. Hydatid cyst (Correct Answer)
- B. Malaria
- C. Filariasis
- D. Dengue fever
Explanation: ***Hydatid cyst*** - This disease is caused by the larval stage of the tapeworm **Echinococcus granulosus**, which completes its life cycle in dogs and sheep. - Humans can become infected by ingesting material contaminated with **Echinococcus eggs**, typically from contact with infected dogs or contaminated food/water, making it a zoonotic disease. *Malaria* - Malaria is transmitted by the **Anopheles mosquito** biting infected humans and then uninfected humans. - While it involves a vector, its primary reservoir is humans and it is not typically considered zoonotic as there is no animal-to-human transmission from a non-human primary reservoir. *Filariasis* - Filariasis is spread by various mosquito vectors (e.g., **Culex, Anopheles, Aedes**) that transmit parasitic worms to humans. - The life cycle primarily involves humans and mosquitos, and it is not classified as a zoonotic disease. *Dengue fever* - Dengue fever is a viral infection transmitted by **Aedes mosquitoes** (primarily *Aedes aegypti* and *Aedes albopictus*) between humans. - Similar to malaria, while it involves a vector, the primary reservoir is humans, and it is not considered zoonotic.
Question 23: Which of the following statements about the Late Expanding Phase of the Demographic Cycle is TRUE?
- A. Death Rate becomes significantly lower than Birth Rate during this phase
- B. Death Rate declines more than Birth Rate (Correct Answer)
- C. Birth Rate remains consistently high while Death Rate starts to decline significantly
- D. Birth Rate remains higher than Death Rate, leading to population growth
Explanation: ***Death Rate declines more than Birth Rate*** - In the **Late Expanding Phase**, the **birth rate** remains high, while the **death rate** continues to fall **rapidly** due to improved healthcare, sanitation, and nutrition. - This significant decline in the death rate, coupled with a still high birth rate, results in a rapid and substantial increase in **population growth** (demographic explosion). - The key characteristic is the **greater rate of decline** in death rate compared to birth rate. *Birth Rate remains consistently high while Death Rate starts to decline significantly* - The word **"starts"** is the critical error here - it describes the **Early Expanding Phase**, not the Late Expanding Phase. - In the **Late Expanding Phase**, the death rate has *already been declining* and continues to decline rapidly. - The death rate decline **begins** in the Early Expanding Phase, not the Late Expanding Phase. *Death Rate becomes significantly lower than Birth Rate during this phase* - While this statement is true, it describes a **consequence** rather than the defining characteristic of the Late Expanding Phase. - This condition exists throughout the expanding phases, making it less specific. - The defining feature is the **rate of decline** of death rate being greater than any decline in birth rate. *Birth Rate remains higher than Death Rate, leading to population growth* - This statement is true but **too generic** - it applies to all expanding phases where population growth occurs. - It does not specifically distinguish the **Late Expanding Phase** from the Early Expanding Phase. - The unique feature of the Late Expanding Phase is the **rapid and dramatic decline** in death rate while birth rate remains high.
Question 24: What does the net reproduction rate indicate?
- A. Number of live births per 1000 mid-year population
- B. Number of live births per 1000 women of child bearing age
- C. Average number of daughters a newborn girl will have during her lifetime (Correct Answer)
- D. None of the options
Explanation: ***Average number of daughters a newborn girl will have during her lifetime*** - The **net reproduction rate (NRR)** specifically measures the average number of **daughters** a newborn girl is expected to have throughout her reproductive years, taking into account **mortality** rates. - An NRR of 1 indicates that each generation of women is exactly replacing itself, while an NRR greater or less than 1 suggests population growth or decline, respectively. - This is the **correct definition** of NRR and focuses on female offspring as they are the ones who will contribute to the next generation. *Number of live births per 1000 mid-year population* - This describes the **crude birth rate (CBR)**, which is a general measure of fertility but does not account for the age and sex structure of the population or mortality rates. - It includes all live births in relation to the total population, not specifically focusing on the generational replacement of females. *Number of live births per 1000 women of child bearing age* - This definition refers to the **general fertility rate (GFR)**, which is a more refined measure of fertility than the crude birth rate, as it focuses on women in their reproductive years (typically 15-49 years). - However, it still does not track the replacement of daughters who will become mothers, nor does it factor in mortality within the female population. *None of the options* - This option is incorrect because one of the given options accurately defines the net reproduction rate. - The net reproduction rate is a well-established demographic indicator used in population studies and public health planning.
Question 25: What is the purpose of work sampling in industrial engineering?
- A. None of the options
- B. Conducted over a short duration
- C. Sampling done for individual tasks
- D. Assessment of how workers spend their time on various activities (Correct Answer)
Explanation: ***Assessment of how workers spend their time on various activities*** - **Work sampling** is a statistical technique used to determine the **proportion of time** that workers spend on different activities. - This method provides insights into **utilization rates**, identifying areas of potential inefficiency or underutilization of resources. *Conducted over a short duration* - While individual observations are brief, **work sampling studies** are typically conducted over an **extended period** to ensure that all variations in work activities and conditions are captured. - A short duration may not provide a **representative sample** of the work activities, leading to inaccurate conclusions. *None of the options* - This option is incorrect because there is a valid purpose for work sampling among the given choices. - Work sampling has a specific and well-defined application in **industrial engineering** for performance analysis. *Sampling done for individual tasks* - Work sampling is not limited to individual tasks; it assesses the **overall distribution of time** spent across various tasks and non-work activities. - It provides a **macro-level view** of how time is allocated within a work environment, rather than a detailed breakdown of each individual task's duration.
Question 26: Child protection scheme is under which ministry?
- A. Ministry of Social Justice and Empowerment
- B. Ministry of Health and Family Welfare
- C. Ministry of Education
- D. Ministry of Women and Child Development (Correct Answer)
Explanation: ***Ministry of Women and Child Development*** - The **Ministry of Women and Child Development** is the nodal ministry in India responsible for formulating and administering laws, policies, and programs concerning women and children, including child protection schemes. - This ministry works to ensure the overall development, welfare, and protection of children, addressing issues such as child abuse, exploitation, and trafficking through various initiatives. *Ministry of Health and Family Welfare* - This ministry primarily deals with **public health**, healthcare services, and family planning, focusing on the health and nutritional aspects of children, but not their overall protection and welfare schemes. - While it contributes to child well-being through health programs, it does not oversee the comprehensive **child protection framework**. *Ministry of Social Justice and Empowerment* - This ministry focuses on the welfare, social justice, and empowerment of **marginalized and vulnerable sections** of society, including persons with disabilities, scheduled castes, and other backward classes. - While it addresses social welfare, its primary mandate is not specific to the overall **child protection scheme**, which falls under a dedicated ministry. *Ministry of Education* - The Ministry of Education is responsible for the **educational system**, including primary, secondary, and higher education. - While it promotes children's development through education, it does not have the mandate for the broader **child protection schemes** that address safety, welfare, and legal aspects beyond schooling.
Question 27: 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 28: Transovarian transmission is seen in which of the following infections?
- A. Plague
- B. Ebola fever
- C. Yellow fever (Correct Answer)
- D. None of the options
Explanation: ***Yellow fever*** - **Transovarian transmission** refers to the passage of a pathogen from an adult female arthropod (like a mosquito) to her offspring via the eggs. This mechanism allows the virus to persist in the **vector population** even in the absence of infected vertebrate hosts. - **Yellow fever virus** is known to undergo transovarian transmission in its mosquito vectors, particularly *Aedes aegypti* and other *Aedes* species. *Plague* - Plague is caused by the bacterium *Yersinia pestis* and is primarily transmitted by **flea bites** from infected rodents to humans. - It does not involve transovarian transmission; the fleas acquire the bacteria during a **blood meal** from an infected host. *Ebola fever* - Ebola virus is transmitted through **direct contact** with blood or bodily fluids of infected humans or animals. - It is not an **arthropod-borne disease** and therefore does not exhibit transovarian transmission. *None of the options* - This option is incorrect because **Yellow Fever** clearly demonstrates transovarian transmission within its mosquito vector.
Question 29: Which of the following diseases does not have a chronic carrier state?
- A. Malaria
- B. Tetanus (Correct Answer)
- C. Measles
- D. Poliomyelitis
Explanation: ***Tetanus*** - Tetanus is caused by the toxin produced by *Clostridium tetani*, which is an **environmental bacterium** found in soil and does not establish a persistent infection within humans. - Humans are merely **accidental hosts** for this bacterium, meaning there is **no chronic carrier state** where an infected individual continuously harbors and transmits the pathogen. - The disease occurs through wound contamination with spores, not human-to-human transmission. *Measles* - Measles is an **acute viral infection** with no chronic carrier state in the classical sense. - After acute infection, the virus is cleared from the body in immunocompetent individuals. - While **subacute sclerosing panencephalitis (SSPE)** represents a rare persistent infection, this is **not a carrier state** as the virus is not transmissible from these individuals. - SSPE occurs years after initial infection but does not involve viral shedding or transmission. *Malaria* - Individuals infected with ***Plasmodium* parasites** can develop a **chronic carrier state**, particularly with *P. vivax* and *P. ovale*, which form hypnozoites in the liver. - These parasites can remain dormant and then reactivate, causing **relapses** and allowing for continued transmission to mosquitoes over extended periods. - Chronic asymptomatic carriers can serve as reservoirs for transmission in endemic areas. *Poliomyelitis* - Individuals infected with poliovirus can shed the virus in their stools for **several weeks to months** after infection. - In **immunodeficient individuals**, prolonged excretion can occur for years, creating chronic carriers. - This prolonged shedding allows for the **continued transmission** of the virus within a population.
Question 30: 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.