Vaccine Safety in the News

1. WHO Reaffirms Safety Monitoring Priorities for High-Risk Pathogens

At its most recent meetings, WHO’s Global Advisory Committee on Vaccine Safety (GACVS) has emphasized the importance of strengthened Adverse Events of Special Interest (AESI) frameworks, real-time reporting, and cross-country data sharing—particularly for pathogens with emerging vaccine pipelines such as Marburg, Lassa fever, and chikungunya.

• Focus: The committee underscores the need for proactive, globally harmonized safety systems rather than only responding to individual outbreaks.
• 🔗 Source (GACVS Reports): WHO Global Advisory Committee on Vaccine Safety Committee Reports
• (For Technical Depth: Find the specific AESI lists for these pathogens at the SPEAC AESI Lists page.)

2. EMA Expands Transparency with Updated EudraVigilance Signal Dashboard

The European Medicines Agency (EMA) continues to implement enhancements to its EudraVigilance safety-signal tools, including improved automation, visualization, and cross-product comparison capabilities. These updates, driven by systems like the EudraVigilance Data Analysis System (EVDAS), are intended to support earlier detection of potential safety signals and ensure more consistent interpretation of vaccine-related Adverse Events of Special Interest (AESIs) across EU member states.

• Focus: Enhanced automation and data harmonization (e.g., mandatory ISO standards reporting since 2022) to support signal detection.
• 🔗 Source (EudraVigilance System): EudraVigilance System Overview and Enhancements

3. Growing Use of AI in Vaccine Signal Detection

A trend highlights how artificial intelligence (AI) and machine learning (ML) are increasingly used to analyze spontaneous reporting systems, electronic health records, and active surveillance platforms for vaccines. Experts caution that AI-generated outputs must be grounded in established, validated clinical frameworks—such as the Brighton Collaboration case definitions—to avoid misclassification or inflation of safety signals.

• Rationale: AI’s potential to process vast, unstructured data requires standardized definitions to ensure outputs are clinically meaningful and reliable.
• 🔗 Source (AI/Pharmacovigilance Review): Artificial intelligence in pharmacovigilance: a narrative review… (PMC12335403)

4. Global Health Agencies Revisit Mpox Vaccine Safety Strategies

Following expanded mpox vaccination campaigns and evolving epidemiology, global health bodies like the WHO and ECDC have reiterated the importance of continued safety monitoring for the MVA-BN and LC16m8 vaccines. Guidance emphasizes targeted surveillance for adverse events like myocarditis/pericarditis and strengthened monitoring in high-risk populations, including pregnant individuals, children, and immunocompromised people.

• High-Risk Focus: WHO SAGE guidance explicitly addresses the safety profile of these vaccines for special populations, recommending MVA-BN (Jynneos) for immunocompromised and pregnant women due to its non-replicating nature.
• 🔗 Source (WHO Mpox Public Advice): WHO Public advice on mpox vaccination and special populations guidance

5. Post-Authorization Safety Assessment of  Chikungunya Vaccines

Regulatory agencies, including the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA), are actively reviewing early post-authorization safety data for the approved chikungunya vaccines, revealing distinct safety profiles based on the vaccine platform.

• Vimkunya (Virus-Like Particle, Bavarian Nordic): Early post-authorization surveillance has supported a favorable safety profile, with no serious adverse events (SAEs) or new safety signals reported to date in systems like the U.S. VAERS or the EU’s EudraVigilance, even in the $\ge 65$-year-old population [Source 1]. Monitoring continues for expected events like arthralgia duration.
• Ixchiq (Live Attenuated, Valneva): Post-marketing surveillance for this vaccine identified serious safety concerns, including reports of severe chikungunya-like illness, hospitalizations, deaths, and one confirmed fatal case of encephalitis linked to the vaccine strain. The FDA initially recommended a pause in use for older adults in May 2025, but subsequently suspended the vaccine’s U.S. Biologics License entirely in August 2025 [Source 2, Source 3]. In contrast, after its own review of serious side effects primarily in the elderly with comorbidities, the EMA lifted its temporary age restriction in July 2025, recommending use only after careful consideration of the benefits and risks [Source 4].

This divergence in post-authorization findings highlights the importance of the ongoing pharmacovigilance process and using harmonized case definitions for AEFI” and highlighting our CHIK AESI list.