NEET-PG 2013 - Community Medicine Practice Questions

Q: Dukoral is:

Oral cholera vaccine. ***Oral cholera vaccine*** - Dukoral is a **killed oral whole-cell vaccine** against *Vibrio cholerae* O1 and O139, often combined with a recombinant B subunit of cholera toxin. - It provides protection against **cholera**, an acute diarrheal illness caused by bacterial infection of the small intestine. *Oral rotavirus vaccine* - Oral rotavirus vaccines (e.g., Rotarix, RotaTeq) provide protection against **rotavirus**, the most common cause of severe diarrhea in infants and young children. - These vaccines are usually given in multiple doses to infants and are distinct from cholera vaccines. *Oral typhoid vaccine* - An oral typhoid vaccine, such as Ty21a, is used for the prevention of **typhoid fever**, caused by *Salmonella Typhi*. - It is a **live attenuated vaccine** administered in several doses over a week, differing significantly from Dukoral's mechanism and target. *Ready to use therapeutic food* - **Ready-to-use therapeutic food (RUTF)** is a high-energy, micronutrient-rich paste used for the treatment of **severe acute malnutrition (SAM)**, especially in children. - It is a nutritional intervention, not a vaccine, and helps in weight gain and recovery for malnourished individuals.

Q: Which of the following characteristics can be used to differentiate the rash of chickenpox from the rash of smallpox?

Pleomorphic. ***Pleomorphic*** - The rash of **chickenpox** is **pleomorphic**, meaning lesions at various stages of development (macules, papules, vesicles, scabs) are present simultaneously in the same body area. - In contrast, a **smallpox** rash is **monomorphic**, with all lesions in a given area appearing at the same stage of development. *Centrifugal* - A **centrifugal distribution** (lesions more concentrated on the face and extremities) is characteristic of **smallpox**. - **Chickenpox** typically has a **centripetal distribution**, with lesions more concentrated on the trunk. *Deep-seated* - **Smallpox** lesions are described as **deep-seated** and feel like "shot under the skin," often associated with significant scarring. - **Chickenpox** lesions are superficial and less likely to cause scarring unless secondarily infected. *Multilocular* - **Smallpox** vesicles and pustules are typically **multilocular**, meaning they have internal septations and do not collapse when punctured. - **Chickenpox** vesicles are unilocular, appearing as a single compartment, and collapse when punctured.

Q: In the context of disease screening, which type of lead time is most beneficial for effective screening?

Long lead time is beneficial for screening. ***Long lead time is beneficial for screening*** - **Long lead time** provides a greater window of opportunity between disease detection by screening and clinical symptom onset - This extended asymptomatic detectable phase allows for **early intervention** when treatments are most effective - Longer lead time correlates with improved prognosis and potential prevention of severe outcomes - Essential criterion for effective screening programs per **Wilson-Jungner criteria** *Short lead time* - Limited time between disease detectability and clinical symptoms - Reduces screening effectiveness as disease progresses rapidly - Minimal opportunity for beneficial early intervention *Both short and long lead times are beneficial* - Only **long lead time** is beneficial for screening programs - Short lead time actually limits screening effectiveness - Screening benefit is directly proportional to duration of asymptomatic detectable phase *Lead time has no impact on screening effectiveness* - **Lead time is crucial** for determining screening program effectiveness - Directly impacts the window for early detection and intervention - Without adequate lead time, screening loses its preventive value

Q: What is the annual infection rate of tuberculosis?

Percentage of new patients positive for tuberculin test. ***Percentage of new patients positive for tuberculin test*** - The **annual infection rate of tuberculosis (AIRT)** is defined as the percentage of individuals (typically children aged 1-9 years) who show **tuberculin conversion** (from negative to positive) in a given year. - Among the given options, this is the **closest representation** as it focuses on **newly infected individuals** rather than prevalent cases. - AIRT is a key epidemiological indicator reflecting **ongoing transmission** and the **annual risk of tuberculous infection** in a community. - This measure helps assess TB control program effectiveness and disease burden. *Percentage of total patients positive for tuberculin test* - This represents the **prevalence of tuberculosis infection** in the population, including both old and new infections. - It does not specifically measure the **annual rate of acquiring new infections**, which is what AIRT captures. *Percentage of sputum positive total patients* - This indicates the **prevalence of active, infectious pulmonary tuberculosis** in a population. - It refers to individuals with **active TB disease** who are shedding bacteria in sputum, not latent infection detected by tuberculin testing. *Percentage of sputum positive new patients* - This represents the **incidence of new, active, infectious tuberculosis cases** (case detection rate). - While important for TB surveillance, it measures **active disease** rather than **infection rate** detected by tuberculin skin test.

Q: According to the immunization schedule, how many doses of influenza vaccine should children under 9 years of age receiving the vaccine for the first time typically receive?

2 doses at 4 weeks interval. ***2 doses at 4 weeks interval*** - Children **under 9 years of age** receiving the influenza vaccine for the **first time** require **two doses** administered at least **4 weeks (28 days) apart**. - This two-dose priming schedule is essential to ensure adequate immune response and protection against circulating influenza strains. - This recommendation is consistent across **IAP (Indian Academy of Pediatrics)** and **CDC guidelines**. - Children 9 years and older, and younger children who have been previously vaccinated, require only **1 dose annually**. *3 doses at 4 weeks interval* - The standard protocol for influenza vaccination does **not involve three doses**. - A three-dose schedule is typically seen with vaccines like **Hepatitis B**, **DTaP**, or **Hib**, but not for influenza. *2 doses at 4 weeks interval with a booster dose for high-risk children* - While high-risk children (chronic lung disease, heart disease, immunocompromised) are priority groups for influenza vaccination, the schedule remains **two initial doses** for first-time recipients under 9 years. - There is **no additional booster dose** beyond the two-dose series within the same influenza season, even for high-risk children. - Subsequent years require only **1 dose annually**. *None of the options* - This is incorrect as the standard recommendation is clearly established in immunization guidelines. - The **two-dose schedule at 4-week intervals** for first-time recipients under 9 years is well-documented by IAP and international guidelines.

Q: At what age is the BCG vaccination administered in India?

At birth. ***At birth*** - In India, the **BCG vaccine** is routinely administered to infants **at birth** or as early as possible thereafter as per the **Universal Immunization Programme (UIP)**. - This early vaccination aims to provide protection against **severe forms of tuberculosis (TB)**, particularly **tuberculous meningitis** and **disseminated (miliary) TB** in young children. - Early administration is crucial as infants are at highest risk of developing severe TB if exposed. *Incorrect: 1 year* - While other vaccinations might be given at 1 year (such as MMR), the BCG vaccine is specifically recommended at or soon after birth. - Delaying BCG vaccination until 1 year increases the risk of early exposure to TB before immunity can be established, defeating its protective purpose. *Incorrect: 2 years* - The recommended schedule for BCG vaccination in India does not include administration at 2 years of age. - By 2 years, potential exposure to TB may have already occurred, and the vaccine's efficacy in preventing severe forms of the disease would be compromised. *Incorrect: 6 weeks* - At 6 weeks, other vaccines like OPV, DPT, Hepatitis B, Hib, and Rotavirus are administered as part of the UIP schedule. - BCG is specifically given at birth, not at 6 weeks, to provide early protection against severe childhood tuberculosis.

Q: Infectivity period of chickenpox is ?

1 day before and 4 days after appearance of rash. ***1 day before and 4 days after appearance of rash*** - The infectivity period of **chickenpox (varicella)** begins approximately **1-2 days (24-48 hours) before the rash appears**. - It extends until **all lesions have crusted over**, which typically occurs around **5-6 days after rash onset**, though some sources cite **4-5 days**. - This option represents the **commonly accepted timeframe** taught in Indian medical curricula and NEET PG examinations. *4 days before and 5 days after appearance of rash* - The **pre-rash infectivity period is too long** in this option; chickenpox is infectious for only **1-2 days before rash**, not 4 days. - While the "5 days after" is medically accurate, the incorrect pre-rash duration makes this option wrong. *Only when scab falls* - This statement is **incorrect**; infectivity starts much earlier, **1-2 days before the rash appears**. - By the time scabs fall, the person is **no longer infectious**, as crusted lesions contain non-infectious material. - This option ignores the critical **pre-rash and early rash infectious period**. *Entire incubation period* - The **incubation period** for chickenpox is usually **10-21 days**, during which the individual is **not infectious** for most of this time. - Infectivity begins only in the **last 1-2 days of incubation** (just before rash onset) and continues into the eruptive phase, not for the entire duration.

Q: Which of the following is the primary component of the AFP (Acute Flaccid Paralysis) case definition used in polio surveillance?

Onset of acute flaccid paralysis. ***Onset of acute flaccid paralysis*** - The primary component of the **AFP case definition** for polio surveillance is the acute onset of **flaccid paralysis** in a child under 15 years, or paralytic illness in a person of any age when polio is suspected. - This definition is crucial for identifying all potential cases of polio, regardless of the cause, to ensure thorough investigation and prevent outbreaks. *Stool specimen positive for poliovirus* - A positive stool specimen for poliovirus is a **laboratory confirmation** of polio infection, but it is not the primary component of the initial case definition. - The AFP case definition aims for **high sensitivity** to capture all possible cases for investigation, even before laboratory results are available. *Presence of residual paralysis after 60 days* - Residual paralysis after 60 days is an important indicator for **classifying a confirmed polio case** and understanding the long-term impact. - However, it is a **follow-up criterion** used after the initial detection of AFP, not the primary component that triggers the initial surveillance. *All of the above* - While laboratory confirmation and residual paralysis provide further information about a case, the **initial identification relies specifically on the clinical presentation** of acute flaccid paralysis. - The broad clinical definition ensures that no potential polio case is missed, initiating an immediate public health response.

Q: Which of the following best defines the concept of 'Quality of Life'?

Subjective feeling of well being. ***Subjective feeling of well being*** - **Quality of Life** is primarily a **subjective measure**, reflecting an individual's personal perception of their well-being and satisfaction with various aspects of their life. - It encompasses physical health, psychological state, social relationships, personal beliefs, and their relationship to their environment. *Standard of living* - **Standard of living** typically refers to the degree of wealth and material comfort available to a person or community. - This is an **objective, economic measure** and does not fully capture the subjective, multi-dimensional aspects of well-being. *Level of living* - The **level of living** is closely related to the standard of living, focusing on the actual conditions of life experienced by individuals, often in terms of material possessions, housing, and access to services. - Like standard of living, it is more about **objective and measurable aspects** of life rather than subjective feelings. *None of the above* - This option is incorrect because "Subjective feeling of well being" accurately defines **Quality of Life**. - **Quality of Life** is a complex, multi-faceted concept that integrates both objective and subjective factors, with the subjective feeling of well-being being central to its definition.

Q: In typhoid, a person is considered a permanent carrier if they excrete bacilli for more than how many months?

1 year. **1 year** - A person is defined as a permanent carrier of typhoid if they excrete **Salmonella Typhi** in their feces or urine for **more than one year** after the acute illness. - This long-term excretion is often associated with chronic infection of the **gallbladder**, particularly in individuals with gallstones. - The definition of chronic/permanent carrier status is set at **≥12 months** of continuous bacillary excretion. *3 months* - Excreting bacilli for 3 months after acute typhoid is considered a **convalescent carrier state**, not a permanent one. - Many individuals clear the infection within this timeframe without becoming chronic carriers. *6 months* - While prolonged, 6 months of excretion still falls under the definition of a **convalescent or temporary carrier**, rather than a permanent carrier. - The threshold for "permanent" or "chronic" carrier status is typically set at 12 months. *3 years* - While a person excreting bacilli for 3 years would certainly be a permanent carrier, the established definition for permanent carrier status is met at **1 year**, not 3 years. - This option represents an unnecessarily longer duration than the standard definition.

Question 1

Dukoral is:

Accepted Answer

Oral cholera vaccine

Answer

Oral rotavirus vaccine

Answer

Oral typhoid vaccine

Answer

Ready to use therapeutic food

Question 2

Which of the following characteristics can be used to differentiate the rash of chickenpox from the rash of smallpox?

Accepted Answer

Pleomorphic

Answer

Deep-seated

Answer

Centrifugal

Answer

Multilocular

Question 3

In the context of disease screening, which type of lead time is most beneficial for effective screening?

Accepted Answer

Long lead time is beneficial for screening

Answer

Short lead time

Answer

Both short and long lead times are beneficial

Answer

Lead time has no impact on screening effectiveness

Question 4

What is the annual infection rate of tuberculosis?

Accepted Answer

Percentage of new patients positive for tuberculin test

Answer

Percentage of total patients positive for tuberculin test

Answer

Percentage of sputum positive total patients

Answer

Percentage of sputum positive new patients

Question 5

According to the immunization schedule, how many doses of influenza vaccine should children under 9 years of age receiving the vaccine for the first time typically receive?

Accepted Answer

2 doses at 4 weeks interval

Answer

2 doses at 4 weeks interval with a booster dose for high-risk children

Answer

3 doses at 4 weeks interval

Answer

None of the options

Question 6

At what age is the BCG vaccination administered in India?

Accepted Answer

At birth

Answer

1 year

Answer

2 years

Answer

6 weeks

Question 7

Infectivity period of chickenpox is ?

Accepted Answer

1 day before and 4 days after appearance of rash

Answer

Only when scab falls

Answer

Entire incubation period

Answer

4 days before and 5 days after appearance of rash

Question 8

Which of the following is the primary component of the AFP (Acute Flaccid Paralysis) case definition used in polio surveillance?

Accepted Answer

Onset of acute flaccid paralysis

Answer

All of the above

Answer

Stool specimen positive for poliovirus

Answer

Presence of residual paralysis after 60 days

Question 9

Which of the following best defines the concept of 'Quality of Life'?

Accepted Answer

Subjective feeling of well being

Answer

Standard of living

Answer

Level of living

Answer

None of the above

Question 10

In typhoid, a person is considered a permanent carrier if they excrete bacilli for more than how many months?

Accepted Answer

1 year

Answer

3 months

Answer

6 months

Answer

3 years

NEET-PG 2013 — Community Medicine