New CDC Study Shows Positive Results for COVID-19 Vaccine Safety

The Pfizer-BioNTech and Moderna COVID-19 vaccines received Emergency Use Authorization (EUA) on December 11, 2020 and December 18, 2020, respectively.¹ A new CDC study is revealing positive information that both COVID-19 vaccines are safe.

The Advisory Committee on Immunization Practices initially recommended in their interim guidance that both health care personnel and residents of long-term care facilities (LTCFs) be offered the COVID-19 vaccine in the initial phase of the vaccination program.² Vaccine safety monitoring has involved the Vaccine Adverse Event Reporting System (VAERS) and v-safe (active surveillance system).^1,3 The v-safe is a smartphone-based surveillance tool that uses text messaging and web surveys to provide personalized health check-ins after receiving a COVID-19 vaccine, and individuals can let the CDC know if they are experiencing any adverse effects.³

The CDC performed a descriptive analysis of safety data for the Pfizer and Moderna COVID-19 vaccines from VAERS and v-safe during the first month of vaccination (December 14, 2020-January 13, 2021). Additionally, 13,794,904 COVID-19 vaccines were administered during the study timeframe.¹ There were 6994 adverse event reports through VAERS, of which 90.8% were classified as nonserious and 9.2% were classified as serious.¹ The most frequently reported adverse effects were headache (22.4%), fatigue (16.5%), and dizziness (16.5%). There were 113 deaths reported to VAERS, of which 65% were among LTCF residents; however, the available information from the surveillance systems indicated the deaths were not associated with the vaccines.¹

Rare cases of anaphylaxis after receiving both vaccines were reported (4.5 reported cases per million doses administered).¹ The median age of individuals reporting adverse events through VAERS was 42 years (range = 15-96 years).¹

Pfizer COVID-19 vaccine adverse reactions reported to the v-safe system were more frequent after receiving the second dose than after the first.¹ Since the Moderna vaccine received its EUA after Pfizer, second dose information was not available at the time of the study for Moderna.¹

During the study period, v-safe enrolled 1,602,065 vaccine recipients who completed at least 1 survey, with 50.8% having received Pfizer, and 49.2% received Moderna vaccines.¹ Injection site pain, fatigue, headache, myalgia, and chills were frequently reported through v-safe.¹ Study limitations include that the VAERS program is based on passive surveillance so there could be bias and underreporting involved.¹ V-safe is a voluntary surveillance system that individuals may not be aware of that requires a smartphone, which can also lead to underreporting due to lack of program knowledge or access.¹

Pharmacists can play an important role in dispelling COVID-19 vaccine myths and countering vaccine hesitancy. Additionally, pharmacists play a critical role in COVID-19 vaccination especially as the vaccine becomes more widely available through community pharmacies. Pharmacists should report any adverse effects associated with COVID-19 vaccines through VAERS and encourage patients and health care professionals to sign up for v-safe after being vaccinated to assist with safety monitoring.

REFERENCES

• Gee J, Marquez P, Su J, et al. First Month of COVID-19 Vaccine Safety Monitoring—United States, December 14, 2020—January 13, 2021. MMWR Morb Mortal Wkly Rep. ePub: 19 February 2021. DOI: http://dx.doi.org/10.15585/mmwr.mm7008e3
• Dooling K, McClung N, Chamberland M, et al. The Advisory Committee on Immunization Practices’ Interim Recommendation for Allocating Initial Supplies of COVID-19 Vaccine—United States, 2020. MMWR Morb Mortal Wkly Rep 2020;69:1857-1859. DOI: http://dx.doi.org/10.15585/mmwr.mm6949e1
• CDC. V-safe after vaccination health checker. Updated February 6, 2021. Accessed February 22, 2021. https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/vsafe.html