With reference to quarantine measures to prevent the spread of a disease, which of the following statements is/are correct? 1. In addition to human beings, quarantine measures are at times also applied to an aircraft or a train or a container etc. 2. The duration of the quarantine period is equivalent to the minimum incubation period for the disease Select the correct answer using the code given below:
Which is the first step in carrying out an Adverse Event Following Immunization (AEFI)?
At the end of an immunization session, you found that a reconstituted BCG vaccine vial has around two doses left in it. What should be done in such a situation?
With reference to Vaccine Vial Monitors (VVM) being used on vaccine vials, which of the following statements is/are correct? 1. It gives information about heat exposure over a period of time 2. It directly indicates vaccine potency Select the correct answer using the code given below:
Why is matching done in a case-control study?
Which of the following vaccines has NOT been introduced in the Universal Immunization Programme in India?
UPSC-CMS 2017 - Community Medicine UPSC-CMS Practice Questions and MCQs
Question 31: With reference to quarantine measures to prevent the spread of a disease, which of the following statements is/are correct? 1. In addition to human beings, quarantine measures are at times also applied to an aircraft or a train or a container etc. 2. The duration of the quarantine period is equivalent to the minimum incubation period for the disease Select the correct answer using the code given below:
- A. 1 only (Correct Answer)
- B. Neither 1 nor 2
- C. 2 only
- D. Both 1 and 2
Explanation: **Statement Analysis:** **Statement 1 - CORRECT:** Quarantine measures are indeed applied beyond human beings to various entities including **aircraft, trains, ships, and containers**. This is a standard practice under International Health Regulations (IHR 2005) to prevent the spread of disease vectors or contaminated goods. For example, during outbreaks of vector-borne diseases, aircraft from affected areas may be disinfected, and containers with potentially contaminated goods can be quarantined for inspection. **Statement 2 - INCORRECT:** The duration of quarantine is equivalent to the **maximum incubation period**, NOT the minimum. This is a fundamental principle of quarantine - it must extend through the longest possible incubation period to ensure that anyone exposed will develop symptoms before release. If quarantine were based on the minimum incubation period, individuals infected later in their exposure could still become infectious after being released from quarantine, defeating its purpose. ***Correct Answer: 1 only*** - **Only statement 1 is correct** - quarantine applies to multiple entities beyond humans - **Statement 2 is incorrect** - quarantine duration is based on maximum, not minimum incubation period - This ensures effective disease containment and prevents asymptomatic spread post-quarantine *Incorrect: 2 only* - Statement 2 is fundamentally flawed regarding quarantine duration principles *Incorrect: Both 1 and 2* - While statement 1 is correct, statement 2 contains a critical error about incubation period *Incorrect: Neither 1 nor 2* - Statement 1 is clearly correct as per international health regulations
Question 32: Which is the first step in carrying out an Adverse Event Following Immunization (AEFI)?
- A. Confirm information in report (Correct Answer)
- B. Collect data about the suspected vaccine
- C. Observe the immunization service in action
- D. Formulate a working hypothesis
Explanation: ***Confirm information in report*** - The initial and crucial step is to **verify the accuracy and completeness of the reported information** to ensure reliable data for further investigation. - This involves checking details such as the **patient's demographics, vaccine administered, date of vaccination, and the reported adverse event** itself. *Collect data about the suspected vaccine* - While essential for an AEFI investigation, **collecting specific vaccine data comes after confirming the initial report**, as you first need a verified event to investigate. - This step focuses on the **vaccine's batch number, expiry date, and manufacturer**, which are vital for causality assessment but not the very first action. *Observe the immunization service in action* - **Observing the immunization service** is a step that might be taken later in an investigation if a program error or procedural issue is suspected, not the immediate first step for an individual AEFI. - This helps identify **potential programmatic errors** in vaccine administration or storage, which is a downstream investigative measure. *Formulate a working hypothesis* - **Formulating a working hypothesis** is part of the analytical phase of an AEFI investigation, which occurs after initial data collection and confirmation, not as the very first step. - A hypothesis guides further investigation into potential causes but requires **initial confirmed data** to be meaningful.
Question 33: At the end of an immunization session, you found that a reconstituted BCG vaccine vial has around two doses left in it. What should be done in such a situation?
- A. Discard the vial in a black coloured bin
- B. Take decision depending upon the Vaccine Vial Monitor (VVM) status
- C. Can reuse the remaining two doses during the next immunization session
- D. Discard the vial in a red coloured bin (Correct Answer)
Explanation: ***Discard the vial in a red coloured bin*** - **Reconstituted BCG vaccine must be discarded at the end of the immunization session** or after **4 hours of reconstitution**, whichever comes first, as per WHO and India's Universal Immunization Programme (UIP) guidelines - This is because reconstituted BCG is **highly susceptible to bacterial contamination** and loses potency over time - **Red coloured bin** is used for **contaminated waste** including discarded vaccine vials in the biomedical waste management system (though yellow bins are sometimes used for pharmaceutical waste) - The multi-dose vial policy based on VVM status applies to **unopened/non-reconstituted vaccines**, not to already reconstituted vaccines *Take decision depending upon the Vaccine Vial Monitor (VVM) status* - VVM status is checked **before opening or reconstituting** the vaccine vial, not after reconstitution - For **reconstituted vaccines** like BCG, the time limit (4 hours or end of session) takes precedence over VVM considerations - VVM-based multi-dose vial policy does not apply to already reconstituted vaccines *Can reuse the remaining two doses during the next immunization session* - This is **completely incorrect** and dangerous - Reconstituted BCG must be discarded after **4 hours** or at the **end of the session**, whichever is earlier - Reusing reconstituted BCG poses serious risks of **bacterial contamination** and **loss of vaccine potency** *Discard the vial in a black coloured bin* - Black bins are used for **general non-hazardous waste**, not for biomedical waste - Vaccine vials must be disposed of as **biomedical waste** in red or yellow bins, not black bins
Question 34: With reference to Vaccine Vial Monitors (VVM) being used on vaccine vials, which of the following statements is/are correct? 1. It gives information about heat exposure over a period of time 2. It directly indicates vaccine potency Select the correct answer using the code given below:
- A. 2 only
- B. Neither 1 nor 2
- C. Both 1 and 2
- D. 1 only (Correct Answer)
Explanation: ***1 only*** - **Vaccine Vial Monitors (VVMs)** are designed to show **cumulative heat exposure** over time, indicating whether a vaccine has been stored within an acceptable temperature range throughout its shelf life. - The color change of the VVM helps healthcare workers determine if a vaccine has been exposed to excessive heat, which can compromise its quality. - VVMs are time-temperature indicators that change color progressively based on both duration and degree of heat exposure. *2 only* - VVMs do **not directly measure vaccine potency**. While excessive heat exposure indicated by a VVM can *imply* reduced potency, the VVM itself does not provide a quantitative measure of a vaccine's effectiveness. - Vaccine potency can only be accurately assessed through specific laboratory tests, not by a visual indicator on the vial. - The VVM is an **indirect indicator** of potential potency loss through monitoring storage conditions. *Neither 1 nor 2* - This is incorrect because statement 1 is accurate - VVMs do provide information about cumulative heat exposure over time. - VVMs are crucial tools in cold chain management for monitoring vaccine storage conditions. *Both 1 and 2* - This is incorrect because while VVMs do indicate heat exposure (statement 1 is correct), they do **not directly** indicate vaccine potency (statement 2 is incorrect). - It's important to differentiate between an indicator of proper storage conditions and a direct measure of efficacy.
Question 35: Why is matching done in a case-control study?
- A. To remove the effect of unknown confounders
- B. To remove the effect of known confounders (Correct Answer)
- C. To eliminate selection bias
- D. To eliminate interviewer’s bias
Explanation: ***To remove the effect of known confounders*** - **Matching** in a case-control study helps to control for the influence of specific variables (known confounders) that might otherwise distort the observed association between the exposure and outcome. - By matching cases and controls on characteristics like age, sex, or socioeconomic status, researchers ensure that these factors are similarly distributed in both groups, isolating the effect of the primary exposure. *To remove the effect of unknown confounders* - Matching is effective for **known confounders** that are identified and controlled during study design. - It does not address the impact of **unknown** or unmeasured confounding variables, which can still influence the study's results. *To eliminate selection bias* - **Selection bias** occurs when participants are not representative of the target population; matching primarily addresses confounding, not the initial selection process. - While careful selection is crucial to minimize selection bias, matching itself is more related to controlling for nuisance variables *after* selection. *To eliminate interviewer’s bias* - **Interviewer bias** (or observer bias) arises when the interviewer's expectations or knowledge influence data collection or interpretation. - This type of bias is typically addressed through blinding (e.g., blinded interviewers, participants, or outcome assessors), not through matching study participants.
Question 36: Which of the following vaccines has NOT been introduced in the Universal Immunization Programme in India?
- A. Injectable polio vaccine
- B. MMR vaccine
- C. Cervical cancer vaccine (Correct Answer)
- D. Pentavalent vaccine
Explanation: ***Cervical cancer vaccine (HPV vaccine)*** ✓ **Correct Answer (as of 2017)** - At the time of this examination (UPSC-CMS 2017), the **HPV vaccine** had NOT been introduced into the Universal Immunization Programme (UIP) in India. - While pilot studies were conducted, nationwide rollout had not occurred. - **Update**: India officially introduced HPV vaccination in the UIP in 2024 for girls aged 9-14 years, but this question reflects the 2017 status. *Injectable polio vaccine (IPV)* - The **Injectable Polio Vaccine (IPV)** was introduced into the UIP in **2015** in a phased manner. - IPV was added alongside the oral polio vaccine (OPV) to provide additional protection and prevent **vaccine-derived poliovirus** cases. - Essential for maintaining India's polio-free status achieved in 2014. *MR vaccine (incorrectly listed as MMR)* - India's UIP includes the **MR vaccine (Measles-Rubella)**, NOT MMR. - **Measles vaccine** was part of UIP since its inception; **Rubella** was added in phased campaigns starting 2017. - **Mumps vaccine is NOT part of routine UIP** - it's only available privately. - The option should technically say "MR vaccine" for accuracy, but MMR was listed in the original question. *Pentavalent vaccine* - The **pentavalent vaccine** was introduced in UIP starting **2011** (phased) and nationwide by 2015. - Protects against five diseases: **Diphtheria, Pertussis, Tetanus, Hepatitis B, and Haemophilus influenzae type b (Hib)**. - Replaced the earlier DPT + Hepatitis B + Hib schedule, reducing injection burden.