Extensive limb swelling after immunization: reports to the Vaccine Adverse Event Reporting System

Area of Science:

• Immunology
• Vaccinology
• Public Health

Background:

• Extensive limb swelling (ELS) is a known adverse event following vaccination.
• Previous reports have linked ELS to a limited range of vaccine types.

Purpose of the Study:

• To identify vaccine types associated with ELS.
• To describe the clinical characteristics of ELS cases reported to the Vaccine Adverse Event Reporting System (VAERS).

Main Methods:

• A case definition for ELS was established (edema extending to the elbow or knee of a vaccinated extremity).
• Data from 497 ELS cases reported to VAERS were analyzed.
• The proportion of ELS reports relative to total reports for each vaccine was calculated.

Main Results:

• ELS cases were identified across a wide age range (0.1 to 91 years).
• Swelling could involve proximal and distal limb segments (e.g., shoulder to hand, hip to foot).
• The incidence of ELS varied significantly among different vaccine types.
• Most ELS reactions occurred within 1 day of vaccination and were accompanied by other inflammatory signs.

Conclusions:

• Postvaccination ELS is not limited to specific vaccine types and can occur after a broad range of immunizations.
• ELS affects individuals across all age demographics.
• The clinical presentation of ELS involves significant limb edema and can be associated with other inflammatory symptoms.