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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. Tachycardia
Measles, Mumps & Rubella (MMR II)×Tachycardia

Tachycardia Reports for Measles, Mumps & Rubella (MMR II)

#147 most reported symptom for this vaccine

338
Reports
6
Deaths
97
Hospitalizations
1.78
Mortality Rate
%
28.7
Hosp. Rate
%

Tachycardia and Measles, Mumps & Rubella (MMR II)

Tachycardia has been reported 338 times in association with Measles, Mumps & Rubella (MMR II) vaccination in VAERS. This represents 0.4% of all 89,976 reports for this vaccine.

Among these reports, 6 mentioned death (1.78%) and 97 involved hospitalization (28.7%).

Tachycardia is the #147 most frequently reported symptom for Measles, Mumps & Rubella (MMR II) out of 2292 total symptoms.

Disclaimer: VAERS reports describe events that occurred after vaccination but do not establish that the vaccine caused the event. Many reported symptoms may be coincidental or related to underlying conditions.

What This Means

Seeing 338 reports of Tachycardia after Measles, Mumps & Rubella (MMR II) vaccination may seem alarming, but context is critical.

The mortality rate of 1.78% warrants monitoring, though VAERS deaths represent temporal associations, not confirmed causal links.

Important Context

•Association, not causation: These reports show Tachycardia occurred after vaccination, not that the vaccine caused it.
•Background rates: Tachycardia may occur naturally at baseline rates in the population, unrelated to vaccination.
•Anyone can report: VAERS accepts reports from anyone — patients, parents, healthcare providers — without requiring medical verification.
•Denominator missing: VAERS counts reports, not rates per dose. Without knowing how many doses were given, raw counts can be misleading. Learn more →

Similarly Ranked Symptoms

Dehydration340 reportsInjection site cellulitis340 reportsLaboratory test335 reportsStaring332 reports

Quick Facts

Reports:338
Deaths:6
Hospitalizations:97
% of Vaccine:0.4%
Rank:#147 of 2292

Related Pages

Measles, Mumps & Rubella (MMR II) OverviewTachycardia (All Vaccines)Why Raw Numbers MisleadTop Symptoms Analysis

Data Source

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