Important: VAERS reports alone cannot determine if a vaccine caused an adverse event. Reports may contain incomplete, inaccurate, or unverified information. Correlation does not equal causation.
From 2,214 reports in 1990 to 768,706 in 2021 — and the journey back to baseline.
The history of VAERS reporting can be divided into three distinct eras:
VAERS started small with just 2,214 reports in its first year. Through the 1990s and early 2000s, annual reports hovered around 10,000-18,000. This was a period of steady, predictable growth as the system matured and awareness increased.
Starting around 2007, reporting jumped to 30,000-50,000 per year. Several factors drove this: the introduction of new vaccines (HPV, rotavirus), increased digital reporting infrastructure, and growing public awareness of VAERS. The pre-COVID decade (2010-2019) averaged about 40,051 reports per year.
The COVID-19 vaccination campaign caused an explosive spike in 2021 (768,706 reports). Since then, reporting has declined 95% from the peak. By 2025, annual reports (40,283) are approaching pre-COVID levels, suggesting the system is returning to its historical baseline.
The decline from the 2021 peak is significant and expected. As COVID-19 vaccination rates dropped, booster uptake declined, and the heightened awareness of VAERS faded, reports returned toward pre-pandemic levels. This pattern confirms that the spike was driven by the pandemic context, not a permanent change in reporting behavior.
Through mid-2026, VAERS reporting continues its normalization trend. Early data suggests 2026 annual reports will land near the 35,000-45,000 range — essentially back to the 2015-2019 baseline. Key factors shaping the current landscape:
The post-pandemic normalization is an important data point: it demonstrates that VAERS's sensitivity to external events (media coverage, public awareness, new vaccine rollouts) is both a feature and a limitation. Understanding these contextual drivers is essential for interpreting any year's data accurately.
As VAERS reporting normalizes following the COVID-19 pandemic surge, the data landscape for VAERS reporting trends over time is shifting. Annual VAERS reports in 2025-2026 have returned to the 35,000-45,000 range typical of the pre-pandemic era (2015-2019), making year-over-year comparisons more meaningful again.
The HHS administration has signaled increased focus on vaccine safety data analysis, including the development of AI-powered tools for pattern detection in VAERS reports. While these tools are still under development, they represent a potential evolution in how adverse event data is analyzed and interpreted.
New vaccines entering the market — including RSV vaccines for older adults and pregnant women, updated COVID-19 formulations, and potential H5N1 avian flu vaccines — continue to add new data streams to VAERS. Each new vaccine type provides additional context for understanding VAERS reporting trends over time across the full spectrum of vaccine safety surveillance.
This analysis is based entirely on VAERS passive surveillance data, which carries important limitations that must be understood:
For these reasons, VAERS data is best used for signal detection — identifying potential safety concerns that warrant further investigation — rather than for definitive risk assessment. When VAERS surfaces a potential signal, it is investigated using more rigorous systems like the Vaccine Safety Datalink (VSD) and controlled epidemiological studies.
All data on VaccineWatch comes from the official VAERS public-use datasets published by the CDC and FDA. Our current dataset covers reports from 1990 through early 2026. We process the raw data without filtering or editorializing — every metric is a transparent aggregation of official government data.
As VAERS reporting normalizes following the COVID-19 pandemic surge, the data landscape for VAERS reporting trends over time is shifting. Annual VAERS reports in 2025-2026 have returned to the 35,000-45,000 range typical of the pre-pandemic era (2015-2019), making year-over-year comparisons more meaningful again.
The HHS administration has signaled increased focus on vaccine safety data analysis, including the development of AI-powered tools for pattern detection in VAERS reports. While these tools are still under development, they represent a potential evolution in how adverse event data is analyzed and interpreted.
New vaccines entering the market — including RSV vaccines for older adults and pregnant women, updated COVID-19 formulations, and potential H5N1 avian flu vaccines — continue to add new data streams to VAERS. Each new vaccine type provides additional context for understanding VAERS reporting trends over time across the full spectrum of vaccine safety surveillance.
This analysis is based entirely on VAERS passive surveillance data, which carries important limitations that must be understood:
For these reasons, VAERS data is best used for signal detection — identifying potential safety concerns that warrant further investigation — rather than for definitive risk assessment. When VAERS surfaces a potential signal, it is investigated using more rigorous systems like the Vaccine Safety Datalink (VSD) and controlled epidemiological studies.
All data on VaccineWatch comes from the official VAERS public-use datasets published by the CDC and FDA. Our current dataset covers reports from 1990 through early 2026. We process the raw data without filtering or editorializing — every metric is a transparent aggregation of official government data.
As VAERS reporting normalizes following the COVID-19 pandemic surge, the data landscape for VAERS reporting trends over time is shifting. Annual VAERS reports in 2025-2026 have returned to the 35,000-45,000 range typical of the pre-pandemic era (2015-2019), making year-over-year comparisons more meaningful again.
The HHS administration has signaled increased focus on vaccine safety data analysis, including the development of AI-powered tools for pattern detection in VAERS reports. While these tools are still under development, they represent a potential evolution in how adverse event data is analyzed and interpreted.
New vaccines entering the market — including RSV vaccines for older adults and pregnant women, updated COVID-19 formulations, and potential H5N1 avian flu vaccines — continue to add new data streams to VAERS. Each new vaccine type provides additional context for understanding VAERS reporting trends over time across the full spectrum of vaccine safety surveillance.
This analysis is based entirely on VAERS passive surveillance data, which carries important limitations that must be understood:
For these reasons, VAERS data is best used for signal detection — identifying potential safety concerns that warrant further investigation — rather than for definitive risk assessment. When VAERS surfaces a potential signal, it is investigated using more rigorous systems like the Vaccine Safety Datalink (VSD) and controlled epidemiological studies.
All data on VaccineWatch comes from the official VAERS public-use datasets published by the CDC and FDA. Our current dataset covers reports from 1990 through early 2026. We process the raw data without filtering or editorializing — every metric is a transparent aggregation of official government data.