All of the following are anthropozoonosis except
To achieve neonatal tetanus elimination, the incidence of neonatal tetanus per 1000 live births should be reduced to less than:
Which day is not included in the pre-exposure prophylaxis dose schedule for the rabies vaccine?
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)?
NEET-PG 2013 - Community Medicine NEET-PG Practice Questions and MCQs
Question 51: All of the following are anthropozoonosis except
- A. Rabies
- B. Plague
- C. Anthrax
- D. Schistosomiasis (Correct Answer)
Explanation: ***Schistosomiasis*** - This is a **human-to-human** disease, even though it involves an intermediate **snail host**. - Its life cycle does not involve transmission of pathogens from vertebrate animals to humans. *Rabies* - Rabies is a classic **anthropozoonosis**, transmitted to humans primarily through the saliva of infected animals, most commonly **dogs** and **bats**. - It involves a pathogen (rabies virus) that cycles between animals and can be transmitted to humans. *Plague* - Plague is an **anthropozoonosis** caused by *Yersinia pestis*, typically transmitted from **rodents** (e.g., rats) to humans via flea bites. - The disease maintains a natural reservoir in wild rodent populations, making it a prime example of animal-to-human transmission. *Anthrax* - Anthrax is an **anthropozoonosis** caused by *Bacillus anthracis*, transmitted to humans from infected **livestock** (e.g., cattle, sheep). - Humans usually acquire the infection through contact with infected animals or their products, or by inhaling spores.
Question 52: To achieve neonatal tetanus elimination, the incidence of neonatal tetanus per 1000 live births should be reduced to less than:
- A. 0.1
- B. 0.5
- C. 1.0 (Correct Answer)
- D. 0.2
Explanation: ***1.0*** - The international target for **neonatal tetanus elimination (NTE)** as defined by WHO/UNICEF is an incidence rate of **less than 1 case per 1,000 live births per year** in every district of a country. - This is the globally recognized threshold for declaring that neonatal tetanus has been eliminated as a public health problem. - Countries achieving this target at the district level are considered to have achieved NTE. *0.1* - While 0.1 per 1,000 live births represents an extremely low incidence, this is not the WHO-defined threshold for **neonatal tetanus elimination**. - The elimination target is less stringent at <1 per 1,000 live births, making disease control achievable while still representing a major public health success. *0.2* - An incidence of 0.2 per 1,000 live births, though very low, is not the internationally recognized threshold for **neonatal tetanus elimination**. - The established WHO/UNICEF target is <1 per 1,000 live births in every district. *0.5* - An incidence of 0.5 per 1,000 live births indicates excellent control of neonatal tetanus but is not the specific cut-off value. - The WHO criterion for elimination is less than 1 case per 1,000 live births per year at the district level.
Question 53: Which day is not included in the pre-exposure prophylaxis dose schedule for the rabies vaccine?
- A. Day 0
- B. Day 7
- C. Day 28
- D. Day 3 (Correct Answer)
Explanation: ***Day 3*** - The standard pre-exposure prophylaxis (PrEP) schedule for rabies vaccine typically involves three doses given on **Day 0, Day 7, and Day 21 or 28**. - A dose on Day 3 is **not part of the standard recommended PrEP schedule**. *Day 0* - This is the **initial dose** in the pre-exposure prophylaxis series for rabies. - It marks the beginning of the vaccination schedule to build immunity. *Day 7* - This is the **second dose** in the pre-exposure prophylaxis series for rabies. - It follows the initial dose and is crucial for developing a robust immune response. *Day 28* - This dose, along with Day 21, can be the **final dose** in the pre-exposure prophylaxis series for rabies, depending on the specific regimen used. - It completes the primary vaccination course to ensure long-lasting protection.
Question 54: 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 55: 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 56: 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 57: 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 58: 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 59: 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 60: 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.