Vaccine pharmacovigilance and vaccine safety surveillance are essential components of public health and modern immunization programs. This introduction covers core concepts such as adverse events following immunization (AEFI), post-marketing surveillance, passive and active reporting systems, signal detection, causality assessment, pharmacoepidemiology methods, risk management plans, and safety communication. B. Pharm students will learn how surveillance systems (like VAERS, VigiBase), Brighton Collaboration case definitions, disproportionality analyses (PRR, ROR), cohort event monitoring, and pregnancy registries protect populations and inform regulatory action. Emphasis is placed on real-world monitoring, data quality, and interpreting background rates to assess vaccine risks. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. What is the primary objective of vaccine pharmacovigilance?
- To develop new vaccines
- To monitor and improve vaccine safety through detection, assessment, and prevention of adverse events
- To manufacture vaccines at scale
- To promote vaccination campaigns
Correct Answer: To monitor and improve vaccine safety through detection, assessment, and prevention of adverse events
Q2. Which term describes any untoward medical occurrence following immunization, not necessarily causally related?
- Adverse drug reaction (ADR)
- Vaccine efficacy
- Adverse event following immunization (AEFI)
- Immunogenicity
Correct Answer: Adverse event following immunization (AEFI)
Q3. Which surveillance system is primarily a passive spontaneous reporting system used in the United States?
- VAERS (Vaccine Adverse Event Reporting System)
- VigiBase
- Sentinel system
- Cohort event monitoring
Correct Answer: VAERS (Vaccine Adverse Event Reporting System)
Q4. What is the key difference between passive and active vaccine safety surveillance?
- Passive surveillance collects only serious events; active collects only mild events
- Passive relies on spontaneous reports; active proactively seeks data through follow-up or sentinel sites
- Passive uses electronic health records; active uses paper reports
- There is no difference
Correct Answer: Passive relies on spontaneous reports; active proactively seeks data through follow-up or sentinel sites
Q5. Which organization maintains the global database VigiBase for suspected adverse drug reactions including vaccines?
- CDC
- WHO Uppsala Monitoring Centre
- EMA
- FDA
Correct Answer: WHO Uppsala Monitoring Centre
Q6. What is a “signal” in vaccine safety surveillance?
- A confirmed causal relationship between vaccine and event
- Any single report of an event
- Information suggesting a new potentially causal association or new aspect of a known association that warrants further investigation
- A vaccine batch number
Correct Answer: Information suggesting a new potentially causal association or new aspect of a known association that warrants further investigation
Q7. Which method is commonly used for disproportionality analysis in spontaneous report databases?
- Randomized controlled trial
- Proportional Reporting Ratio (PRR)
- Kaplan-Meier survival analysis
- Enzyme-linked immunosorbent assay (ELISA)
Correct Answer: Proportional Reporting Ratio (PRR)
Q8. Brighton Collaboration is best known for providing what resource for vaccine safety?
- Vaccine manufacturing guidelines
- Standardized case definitions for adverse events following immunization
- Cold chain equipment lists
- Marketing strategies for vaccines
Correct Answer: Standardized case definitions for adverse events following immunization
Q9. In causality assessment of AEFI, which factor increases the likelihood that an event is vaccine-related?
- Temporal relationship consistent with known biological mechanism
- Occurrence in a patient with multiple comorbidities
- Absence of biological plausibility
- Long interval of years between vaccination and event
Correct Answer: Temporal relationship consistent with known biological mechanism
Q10. Which approach is used to estimate background rates and compare observed versus expected events after vaccination?
- Case series without denominators
- Observed-versus-expected analysis using population incidence rates
- In vitro neutralization assays
- Descriptive reporting only
Correct Answer: Observed-versus-expected analysis using population incidence rates
Q11. What is cohort event monitoring in vaccine safety?
- Randomized trial of vaccine efficacy
- Active follow-up of a defined cohort of vaccine recipients to systematically collect adverse event data
- Passive reporting to national databases
- Laboratory testing of vaccine potency
Correct Answer: Active follow-up of a defined cohort of vaccine recipients to systematically collect adverse event data
Q12. Which statistical measure compares the odds of reporting a specific event for one vaccine versus all other vaccines?
- Relative Risk
- Reporting Odds Ratio (ROR)
- Incidence Rate Difference
- Hazard Ratio
Correct Answer: Reporting Odds Ratio (ROR)
Q13. Which concept describes non-specific reactions due to anxiety or stress around immunization rather than the vaccine product?
- Immunogenicity
- Vaccine failure
- Immunization stress-related response (ISRR)
- Adjuvant reaction
Correct Answer: Immunization stress-related response (ISRR)
Q14. What is the role of a vaccine risk management plan (RMP)?
- To develop adjuvants for vaccines
- To outline known and potential risks and mitigation measures including post-marketing surveillance activities
- To calculate vaccine efficacy percentages
- To distribute vaccines to clinics
Correct Answer: To outline known and potential risks and mitigation measures including post-marketing surveillance activities
Q15. Why are pregnancy exposure registries important in vaccine safety?
- To test vaccine effectiveness in newborns only
- To collect prospective safety data on vaccine exposures during pregnancy and outcomes for mother and fetus
- To replace clinical trials entirely
- To monitor storage temperatures
Correct Answer: To collect prospective safety data on vaccine exposures during pregnancy and outcomes for mother and fetus
Q16. Which element is essential for traceability in vaccine safety investigations after an AEFI?
- Patient blood type
- Vaccine batch/lot number and manufacturer
- Clinician salary details
- Global vaccine stock levels
Correct Answer: Vaccine batch/lot number and manufacturer
Q17. What challenge is specific to interpreting vaccine safety signals during a mass immunization campaign?
- Too few people vaccinated to detect events
- Increased background noise and coincidental events due to large numbers vaccinated in a short time
- Complete elimination of AEFIs
- Unavailable vaccines for testing
Correct Answer: Increased background noise and coincidental events due to large numbers vaccinated in a short time
Q18. Which outcome would most likely prompt immediate regulatory action after signal evaluation?
- Mild local injection site soreness only
- A plausible causal link between vaccine and a rare but serious adverse event with consistent evidence
- Increase in vaccine uptake
- Decreased immunogenicity in animal models
Correct Answer: A plausible causal link between vaccine and a rare but serious adverse event with consistent evidence
Q19. Which of the following is NOT typically part of a causality assessment algorithm for AEFI?
- Temporal relationship
- Biological plausibility
- Dechallenge/rechallenge information
- Vaccine marketing budget
Correct Answer: Vaccine marketing budget
Q20. Sentinel surveillance sites are useful because they:
- Provide exhaustive national data on every vaccinated individual
- Offer detailed, quality-controlled data from selected sites to detect signals early
- Replace the need for spontaneous reporting
- Only monitor vaccine storage
Correct Answer: Offer detailed, quality-controlled data from selected sites to detect signals early
Q21. Which regulatory database typically aggregates national spontaneous reports from many countries for global analysis?
- Medline
- VigiBase
- ClinicalTrials.gov
- EU Clinical Trials Register
Correct Answer: VigiBase
Q22. For signal validation, triangulation of evidence may include:
- Only one spontaneous report
- Multiple data sources such as spontaneous reports, electronic health records, and epidemiological studies
- Marketing surveys
- Vaccine pricing data
Correct Answer: Multiple data sources such as spontaneous reports, electronic health records, and epidemiological studies
Q23. What is the main advantage of using electronic health records (EHR) in vaccine safety surveillance?
- They eliminate the need for clinical judgment
- They allow linkage of vaccination data with clinical outcomes enabling active surveillance and rapid assessment
- They automatically prove causality
- They replace the need for national reporting systems
Correct Answer: They allow linkage of vaccination data with clinical outcomes enabling active surveillance and rapid assessment
Q24. Which term refers to the statistical threshold often used to prioritize signals in disproportionality analysis?
- pH value
- Signal-to-noise ratio
- Lower 95% confidence limit of PRR > 1 or PRR ≥ 2 with chi-square criteria depending on method
- LD50
Correct Answer: Lower 95% confidence limit of PRR > 1 or PRR ≥ 2 with chi-square criteria depending on method
Q25. How should a pharmacist or healthcare worker handle a suspected AEFI report?
- Ignore it if mild
- Document details, report promptly to the national system, and provide appropriate clinical care
- Only inform the vaccine manufacturer
- Destroy the vaccination records
Correct Answer: Document details, report promptly to the national system, and provide appropriate clinical care
Q26. Which population subgroup often requires targeted vaccine safety monitoring due to differing risk profiles?
- Healthy young adults only
- Pregnant women, immunocompromised individuals, and children
- Only healthcare workers
- People who never travel
Correct Answer: Pregnant women, immunocompromised individuals, and children
Q27. What is an important consideration when communicating vaccine safety risks to the public?
- Avoid any mention of adverse events
- Provide transparent, balanced information about benefits and risks using clear language to maintain trust
- Only use technical jargon
- Delay communication until all studies are complete
Correct Answer: Provide transparent, balanced information about benefits and risks using clear language to maintain trust
Q28. Which type of study design is most appropriate for estimating relative risk of a rare adverse event with a large exposed population?
- Case-control study
- Cross-sectional survey
- In vitro study
- Descriptive case report only
Correct Answer: Case-control study
Q29. Which factor can limit the usefulness of spontaneous reporting systems for vaccine safety?
- Under-reporting and variable data quality
- High cost of vaccines
- Universal active follow-up
- Automatic causality assessment
Correct Answer: Under-reporting and variable data quality
Q30. Why is understanding background incidence rates crucial in vaccine safety assessment?
- Because they are irrelevant to signal detection
- To determine whether the number of observed events after vaccination exceeds what would be expected by chance in the population
- To measure vaccine potency
- To design vaccination schedules only
Correct Answer: To determine whether the number of observed events after vaccination exceeds what would be expected by chance in the population

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.
Mail- Sachin@pharmacyfreak.com

