What is a limitation of the case fatality rate?
Which of the following statements about incidence is false?
India started 2-dose vaccination strategy for measles, in -
Which of the following vaccines is not typically given in disaster situations?
Which of the following best defines the concept of 'Quality of Life'?
In the context of disease screening, which type of lead time is most beneficial for effective screening?
Dukoral is:
What is the annual infection rate of tuberculosis?
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?
What is the most common cause of infant mortality in developing countries?
NEET-PG 2013 - Community Medicine NEET-PG Practice Questions and MCQs
Question 21: What is a limitation of the case fatality rate?
- A. Not useful in acute infectious disease
- B. Not related to virulence
- C. Time period not specified (Correct Answer)
- D. It is not related to survival rate
Explanation: ***Time period not specified*** - The **case fatality rate (CFR)** is sometimes presented without a clear time frame, making it difficult to compare across different studies or diseases. - A CFR calculated over **24 hours** is vastly different from one calculated over **30 days** or **one year**, yet both could be presented simply as "CFR" *Not useful in acute infectious disease* - The CFR is highly **useful** in acute infectious diseases, as it directly measures the **severity** and immediate impact of an outbreak. - It helps public health officials understand the **lethality** of an infectious agent and aids in resource allocation and intervention strategies. *Not related to virulence* - **Case fatality rate** is directly related to **virulence**, as it reflects the proportion of affected individuals who die from the disease. - A higher CFR indicates a more **virulent pathogen** or a more severe disease process. *It is not related to survival rate* - The **case fatality rate** is inherently linked to the **survival rate**; they are complementary measures. - If the CFR is X%, then the associated survival rate is (100 - X)%, representing the proportion of cases that do not die from the disease.
Question 22: Which of the following statements about incidence is false?
- A. Does not include unit of time (Correct Answer)
- B. It is a rate
- C. Numerator includes new cases
- D. Denominator includes population at risk
Explanation: ***Does not include unit of time*** - This statement is false because **incidence** is defined as the number of **new cases** of a disease over a specific period of time in a population at risk. - Therefore, it inherently includes a **unit of time** (e.g., per year, per month), making this option incorrect as a characteristic of incidence. *It is a rate* - **Incidence is a rate** because it quantifies the speed at which new cases of a disease occur within a population. - It expresses the number of new events (cases) per unit of population at risk over a specified time period. *Numerator includes new cases* - The **numerator of incidence** specifically counts the number of **new cases** of a disease that develop during a defined observation period. - This distinguishes it from prevalence, which includes all existing cases. *Denominator includes population at risk* - The **denominator for incidence** comprises the **population at risk** of developing the disease during the observation period. - Individuals who already have the disease or are immune are typically excluded from the denominator.
Question 23: India started 2-dose vaccination strategy for measles, in -
- A. 2008
- B. 2009
- C. 2010 (Correct Answer)
- D. 2011
Explanation: ***2010*** - India implemented the **two-dose measles vaccination strategy** as part of its Universal Immunization Program starting in **2010**. - This decision was based on recommendations to improve immunity and reduce measles incidence, moving from a single-dose to a more effective **two-dose schedule**. *2008* - While important immunization initiatives were ongoing, the specific policy of a **two-dose measles vaccination strategy** had not yet been introduced in India during 2008. - At this time, the focus was primarily on ensuring high coverage of the **first dose** of measles vaccine. *2009* - The year 2009 saw continued efforts to strengthen the Universal Immunization Program, but the official launch of the **two-dose measles vaccination strategy** in India occurred later. - Discussions and planning for the transition were likely underway, but implementation began in the subsequent year. *2011* - By 2011, the **two-dose measles vaccination strategy** was already being implemented across India, having been introduced in 2010. - This year marked a period of expanding coverage and consolidation of the new 2-dose schedule rather than its initial introduction.
Question 24: Which of the following vaccines is not typically given in disaster situations?
- A. Influenza (Correct Answer)
- B. Measles
- C. Cholera
- D. Tetanus
Explanation: ***Influenza*** - **Influenza vaccination** is generally **NOT a priority** in acute disaster response and emergency vaccination campaigns. - While influenza can spread in crowded conditions, routine disaster response protocols focus on **immediately life-threatening and epidemic-prone diseases** rather than seasonal respiratory infections. - Influenza vaccination requires **cold chain maintenance** and repeated doses, making it logistically challenging in emergency settings. - WHO and SPHERE guidelines do not list influenza among priority vaccines for disaster situations unless there is a specific ongoing outbreak. *Cholera* - **Oral cholera vaccine (OCV)** is increasingly recommended by WHO for disaster settings with **high cholera risk**, particularly in areas with poor water and sanitation. - Modern OCVs (like Shanchol and Euvichol) have improved **cost-effectiveness** and logistics, making them viable for mass campaigns. - Used in conjunction with **WASH interventions** (water, sanitation, hygiene) for comprehensive cholera control. *Measles* - **Measles vaccination** is the **highest priority** vaccine in disaster response, particularly for children aged 6 months to 15 years. - Its **extreme contagiousness** (R0 = 12-18) and high mortality in malnourished populations make it critical. - WHO recommends measles vaccination within the **first days** of a disaster response in displacement settings. *Tetanus* - **Tetanus toxoid** (often as Td or DT) is essential in disasters involving injuries, floods, earthquakes, or debris. - Protects against **_Clostridium tetani_** infection from contaminated wounds. - Part of standard **wound management protocols** in emergency medical care.
Question 25: Which of the following best defines the concept of 'Quality of Life'?
- A. Standard of living
- B. Level of living
- C. Subjective feeling of well being (Correct Answer)
- D. None of the above
Explanation: ***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.
Question 26: In the context of disease screening, which type of lead time is most beneficial for effective screening?
- A. Short lead time
- B. Both short and long lead times are beneficial
- C. Long lead time is beneficial for screening (Correct Answer)
- D. Lead time has no impact on screening effectiveness
Explanation: ***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
Question 27: Dukoral is:
- A. Oral cholera vaccine (Correct Answer)
- B. Oral rotavirus vaccine
- C. Oral typhoid vaccine
- D. Ready to use therapeutic food
Explanation: ***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.
Question 28: What is the annual infection rate of tuberculosis?
- A. Percentage of total patients positive for tuberculin test
- B. Percentage of new patients positive for tuberculin test (Correct Answer)
- C. Percentage of sputum positive total patients
- D. Percentage of sputum positive new patients
Explanation: ***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.
Question 29: 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?
- A. 2 doses at 4 weeks interval with a booster dose for high-risk children
- B. 2 doses at 4 weeks interval (Correct Answer)
- C. 3 doses at 4 weeks interval
- D. None of the options
Explanation: ***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.
Question 30: What is the most common cause of infant mortality in developing countries?
- A. Low Birth Weight (LBW) (Correct Answer)
- B. Injuries
- C. Tetanus infection
- D. Birth asphyxia
Explanation: ***Low Birth Weight (LBW)*** - **Low birth weight** (<2500g) is the **single most important underlying factor** contributing to infant mortality in developing countries, accounting for 60-80% of neonatal deaths. - LBW increases vulnerability to **multiple direct causes of death** including respiratory distress syndrome, hypothermia, hypoglycemia, infections (sepsis, pneumonia), and intraventricular hemorrhage. - In developing countries, LBW results primarily from **intrauterine growth restriction** (maternal malnutrition, infections) and **preterm birth**, both highly prevalent due to poor maternal health and limited antenatal care. - As an epidemiological marker, LBW is the **strongest predictor** of infant mortality risk in resource-limited settings. *Injuries* - Injuries are **not a significant cause** of infant mortality (deaths in the first year of life). - Injury-related deaths primarily affect **older children** and become more common after age 1 year, particularly from accidents, falls, burns, and drowning. - In the neonatal period and infancy, biological and perinatal factors far outweigh environmental injuries as mortality causes. *Tetanus infection* - **Neonatal tetanus** was historically a major cause of infant deaths in developing countries, resulting from unhygienic cord care practices and lack of maternal immunization. - Due to successful **maternal tetanus toxoid vaccination programs** and improved delivery practices, neonatal tetanus has been largely eliminated in most regions. - Current incidence is dramatically reduced, making it a **less common cause** compared to LBW-related complications. *Birth asphyxia* - **Birth asphyxia** (intrapartum-related hypoxic injury) is indeed a **major direct cause** of neonatal mortality, accounting for approximately 23% of neonatal deaths globally. - However, many cases of birth asphyxia occur in **low birth weight infants** who are more vulnerable to hypoxic injury. - While birth asphyxia is a critical specific cause, **LBW as a broader risk category encompasses more pathways to death** and affects a larger proportion of infant mortality, making it the most common underlying contributor in developing countries.