What process do CDC and FDA use to investigate VAERS death reports for causality?
This fact-check may be outdated. Consider refreshing it to get the most current information.
Executive summary
VAERS is a passive public early-warning system co-managed by CDC and FDA that collects any reported adverse event following vaccination but is not designed to establish causality [1] [2]. CDC and FDA clinicians screen VAERS death reports, seek medical records, death certificates and autopsy reports, and perform clinical review and epidemiologic follow-up when signals are detected; the official certification of cause of death rests with the death certifier or pathologist, not VAERS itself [3] [4] [5].
1. What VAERS is and what it is not
VAERS accepts reports from healthcare providers, patients, caregivers and manufacturers of any adverse event after vaccination and therefore contains both coincidental and potentially vaccine-caused events; by design it collects raw signals rather than verified causal findings, and the agencies warn that reports alone cannot establish cause and effect [1] [3] [6].
2. Immediate agency triage: physician review and record requests
CDC and FDA physicians review each VAERS report of death as soon as notified and routinely follow up on serious reports to obtain additional medical records, laboratory data, death certificates and autopsy reports to better characterize the event beyond the initial submission [4] [3] [2].
3. Who determines the cause of death in these cases
While CDC and FDA clinicians conduct case-level reviews, the formal determination of cause of death is made by the certifying official who completes the death certificate or by the pathologist who conducts an autopsy; VAERS and agency reviewers use those documents and medical records to assess plausibility, not to replace the certifier’s official finding [4].
4. From single reports to safety signals and investigations
VAERS’s primary utility is detecting unusual patterns or disproportionate reporting that become safety signals; when an initial evaluation suggests a signal, CDC and FDA may conduct deeper clinical reviews and then move to more robust epidemiologic studies in other data systems such as the Vaccine Safety Datalink (VSD) to test causality with comparative rates and controlled methods [5] [7].
5. Data corrections, follow-up limitations and historical context
Past agency work has shown that preliminary VAERS information can differ from final cause-of-death findings—an FDA study found substantial changes in some historical cases—and CDC and FDA have long noted that additional investigation is usually required to validate signals from VAERS [8] [7]. At the same time, VAERS public files typically display the initial report even after follow-up, so public-facing entries may not reflect later clinical adjudication [3].
6. Transparency, potential misuse, and competing narratives
CDC and FDA have expanded public access to VAERS data to increase transparency, but both agencies caution that raw counts are not proof of causality and that misuse of passive-report databases can produce misleading claims; critics and some outside analysts have nevertheless mined VAERS to allege causal links, prompting public debate about appropriate interpretation and the need for controlled epidemiologic analysis [1] [9] [10].
7. Practical takeaway about causality assessment
Determining whether a vaccine caused a death is a multistep process: passive-report detection (VAERS), clinical record and autopsy review by agency physicians, formal death certification by certifiers/pathologists, and—when necessary—epidemiologic studies in linked, population-based data to compare observed versus expected rates; a VAERS report alone does not establish causality [3] [4] [5] [7].