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Data source: VAERS (Vaccine Adverse Event Reporting System)

Data through 2026 · Updated quarterly

Built by TheDataProject.ai · © 2026 VaccineWatch

Important: VAERS accepts reports of adverse events following vaccination. For any given report, there is no certainty that the reported event was caused by the vaccine. Reports may contain information that is incomplete, inaccurate, coincidental, or unverifiable. Most reports to VAERS are voluntary, which means they are subject to biases. This data cannot be used to determine if vaccines cause or contribute to adverse events.

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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.

  1. Home
  2. Vaccines
  3. Measles, Mumps & Rubella (MMR II)
  4. 2021
Measles, Mumps & Rubella (MMR II)2021

Measles, Mumps & Rubella (MMR II) in 2021

1,431 adverse event reports (+19% vs 2020)

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1,431
Reports
5
Deaths
46
Hospitalizations
134
ER Visits
27
Disabilities
← 2020 (1,205 reports)2022 (1,385 reports) →

2021 Reporting Summary

In 2021, 1,431 adverse event reports were filed for Measles, Mumps & Rubella (MMR II) in VAERS. This represents 1.6% of all 89,976 reports for this vaccine.

Of these reports, 5 mentioned death, 46 involved hospitalization, 134 required ER visits, and 27 reported disability.

Compared to the average of 2,391 reports per year for this vaccine, 2021 was below average (-40%).

💡 What This Means

In 2021, reporting for Measles, Mumps & Rubella (MMR II) was within typical ranges. As always, VAERS data reflects reports filed, not confirmed adverse events. Trends should be interpreted alongside vaccination volume and population health data.

All Years for Measles, Mumps & Rubella (MMR II)

YearReportsDeathsHosp.
20251,629360
20241,5711240
20231,362335
20221,385230
2021 ← current1,431546
20201,205555
20192,526893
20181,787357
20172,514280
20162,744781
20153,1621585
20142,502283
20132,231374
20122,35312113
20112,51311138
20103,1485144
20093,14530159
20083,24811134
20072,2758105
20063,47915161
20053,78510159
20044,1787165
20034,15810166
20023,6049161
20013,08316189
20002,47010155
19992,16718163
19981,9269151
19972,06412176
19962,00412182
19952,06611219
19942,05311218
19931,80313188
19922,13417211
19912,14310226
1990228544

Understanding Yearly Data

•Spikes may reflect awareness: Years with unusual activity (e.g., pandemic) often see increased reporting.
•Dose volume matters: More vaccinations given in a year naturally leads to more reports.
•Reporting lag: Some events are reported months after they occur, so recent years may be incomplete.

Quick Facts

Reports:1,431
Deaths:5
Hospitalizations:46
% of Total:1.6%
Rank (by vol.):#32 of 36 years
Avg/year:2,391

Related Pages

Measles, Mumps & Rubella (MMR II) Overview← 2020 Reports2022 Reports →35 Years of ReportingCompare Vaccines

Data Source

This data comes from the Vaccine Adverse Event Reporting System (VAERS), jointly managed by CDC and FDA.