V-safe Publications
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Woo EJ, Gee J, Marquez P, Baggs J, Abara WE, McNeil MM, Dimova RB, Su JR. Post-authorization safety surveillance of Ad.26.COV2.S vaccine: Reports to the Vaccine Adverse Event Reporting System and v-safe, February 2021-February 2022. Vaccine. 2023 Jul 5; https://doi.org/10.1016/j.vaccine.2023.06.023 Online ahead of print.
Myers TR, Marquez PL, Gee JM, Hause AM, Panagiotakopoulos L, Zhang B, McCullum I, Licata C, Olson CK, Rahman S, Kennedy SB, Cardozo M, Patel CR, Maxwell L, Kallman JR, Shay DK, Shimabukuro TT. The v-safe after vaccination health checker: Active vaccine safety monitoring during CDC’s COVID-19 pandemic response. Vaccine. 2023 Jan 23; https://doi.org/10.1016/j.vaccine.2022.12.031 Online ahead of print.
CDC’s V-safe vaccine safety monitoring system supplements existing vaccine safety monitoring programs including the Vaccine Adverse Event Reporting System (VAERS) and the Vaccine Safety Datalink (VSD). V-safe provides near real-time reporting of how people feel following vaccination and encourages reports to VAERS from V-safe participants who sought medical care following vaccination. V-safe also supports the identification of candidates for enrollment in a large post-vaccination pregnancy registry. This February 2023 publication provides an overview of how V-safe works, how it is used, and how updates to the platform have been completed.
Tompkins LK, Baggs J, Myers TR, Gee JM, Marquez PL, Kennedy SB, Peake D, Dua D, Hause AM, Strid P, Abara W, Rossetti R, Shimabukuro TT, Shay DK. Association between history of SARS-CoV-2 infection and severe systemic adverse events after mRNA COVID-19 vaccination among U.S. adults. Vaccine. 2022 Dec 12;S0264-410X(22)01342-1. Online ahead of print.
This study, published in December 2022, found that after receiving the first of two doses of an mRNA COVID-19 vaccine, patients who had previously tested positive for COVID-19 were somewhat more likely to have a severe systemic reaction to the vaccine compared to those who had not had COVID-19 previously. Though these reactions were rare, people who received the Moderna vaccine had a slightly higher risk of complications compared to participants who received the Pfizer-BioNTech vaccine. The study reviewed data from patients 18 years of age and older who had received a COVID-19 vaccination within the previous seven days and registered on CDC’s V-safe. V-safe is a web-based tool that uses text messages, emails, and web surveys to provide personalized health check-ins for people after receiving a new vaccine.
Hause AM, Marquez P, Zhang B, Myers TR, Gee J, Su JR, Blanc PG, Thomas A, Thompson D, Shimabukuro TT, Shay DK. Safety Monitoring of Bivalent COVID-19 mRNA Vaccine Booster Doses Among Persons Aged ≥ 12 Years – United States, August 31 – October 23, 2022. MMWR Morb Mortal Wkly Rep. 2022 Nov 4; 71(44);1401–1406.
This CDC study, published November 2022, found that among people aged 12 years and older who received a bivalent mRNA COVID-19 vaccine booster dose, serious adverse events were rare. Common side effects were headache, fever, fatigue, pain where the shot was given, and chills. The study’s preliminary findings support the overall safety of bivalent mRNA COVID-19 vaccines. Health impacts associated with the original mRNA and the bivalent mRNA COVID-19 vaccines are less frequent and less serious than COVID-19 illness.
During August 31–October 23, 2022, approximately 4.7 million people aged 12 years and older received a dose of the Pfizer-BioNTech bivalent mRNA COVID-19 booster, and approximately 2.6 million people aged 18 years and older received a dose of the Moderna bivalent mRNA COVID-19 booster. CDC reviewed health impact assessments received by CDC’s V-safe and reviewed reports voluntarily submitted to the Vaccine Adverse Event Reporting System during August 31–October 23, 2022, to characterize the safety of bivalent mRNA COVID-19 booster vaccination among people in this age group. The initial safety findings for bivalent mRNA COVID-19 vaccines were generally like those from pre-authorization clinical trials. Data identified no unusual or unexpected patterns of adverse events following vaccination with the Pfizer-BioNTech or Moderna bivalent mRNA COVID-19 vaccines. Reports of serious adverse events following receipt of bivalent COVID-19 vaccine booster doses were rare. Commonly reported reactions such as headache, fever, fatigue, injection-site pain, and chills, were mild and like those reported following receipt of the monovalent mRNA COVID-19 booster dose.
Hause AM, Marquez P, Zhang B, Myers TR, Gee J, Su JR, Parker C, Thompson D, Panchanathan SS, Shimabukuro TT, Shay DK. COVID-19 mRNA Vaccine Safety Among Children Aged 6 Months–5 Years — United States, June 18, 2022–August 21, 2022. MMWR Morb Mortal Wkly Rep. 2022 Sep 2;71(35);1115-1120.
This study, published September 2022, found that among children ages 6 months to 5 years who received mRNA COVID-19 vaccines, local and systemic reactions were mostly mild or moderate. Serious reports of adverse events were rare. Safety data from the Vaccine Adverse Event Reporting System and V-safe were used to look at reported reactions in this age group. Most reported reactions—such as injection site pain, irritability, crying, and sleepiness—were consistent with those observed during the vaccines’ preauthorization clinical trials. This study reinforces the safety profile of mRNA COVID-19 vaccination among children in this age group.
Hause AM, Baggs J, Marquez P, Myers TR, Su JR, Hugueley B, Thompson D, Gee J, Shimabukuro TT, Shay DK. Safety Monitoring of Pfizer-BioNTech COVID-19 Vaccine Booster Doses Among Children Aged 5–11 Years — United States, May 17–July 31, 2022. MMWR Morb Mortal Wkly Rep. 2022 Aug 19;71(33);1047–1051.
A CDC study published August 2022 found that among children ages 5–11 years who received a booster dose of Pfizer-BioNTech’s mRNA COVID-19 vaccine (third dose administered ≥5 months after the second dose), serious reports of adverse events were rare. Data from V-safe and the Vaccine Adverse Event Reporting System were used to look at adverse events reported in this age group. Data showed children that received a third dose had similar adverse events to those reported after receiving a first or second dose. Most reported adverse events—such as injection site pain and headache—were considered mild. The findings are consistent with those observed during the vaccine’s clinical trial and reinforces the safety of mRNA COVID-19 booster dose vaccination among children ages 5–11 years.
Wong KK, Heilig CM, Hause A, Myers TR, Olson CK, Gee J, Marquez P, Strid P, Shay DK. Menstrual irregularities and vaginal bleeding after COVID-19 vaccination reported to v-safe active surveillance, USA in December, 2020-January, 2022: an observational cohort study. Lancet Digit Health. 2022 Aug 9; S2589-7500(22)00125-X. Online ahead of print.
In this study, published August 2022, CDC vaccine safety experts found that menstrual irregularities and vaginal bleeding have been reported among people who received COVID-19 vaccines. These reports were most often about menstrual cycle timing and the severity of menstrual symptoms. During December 14, 2020, through January 9, 2022, researchers analyzed data from V-safe, a web-based tool that uses text messages, emails, and web surveys to provide personalized health check-ins for people after receiving a new vaccine. Researchers identified 84,943 responses to open-ended survey questions related to menstruation or vaginal bleeding from 63,815 V-safe participants ages 18 years and older. Most respondents reported changes to the timing (i.e., cycle beginning earlier or later than expected, missed cycles, and spotting) and the severity (i.e., heavier flow, more painful than usual, or prolonged bleeding) of menstrual symptoms after COVID-19 vaccination. More respondents reported symptoms after their second vaccine dose compared with their first vaccine dose. While researchers acknowledge that an association between COVID-19 vaccination and menstrual irregularities is plausible, they also note that menstrual irregularities are common without COVID-19 vaccination and suggest that further studies are needed to assess clinical significance of menstrual irregularities after vaccination.
Hause AM, Baggs J, Marquez P, Abara WE, Baumblatt J, Blanc PG, Su JR, Hugueley B, Parker C, Myers TR, Gee J, Shimabukuro TT, Shay DK. Safety Monitoring of COVID-19 mRNA Vaccine Second Booster Doses Among Adults Aged ≥50 Years — United States, March 29, 2022–July 10, 2022. MMWR Morb Mortal Wkly Rep. 2022 Jul 29;71(30);971–976.
This analysis, published July 2022, reviewed vaccine safety data from V-safe and the Vaccine Adverse Event Reporting System after receipt of a second COVID-19 mRNA (Pfizer-BioNTech or Moderna) booster dose among adults ages 50 years and older from March 29–July 10, 2022. Vaccine safety experts identified no new safety concerns following the second mRNA booster dose in this age group. Local (itching, pain, redness, and/or swelling at the injection site) and systemic (fever, headache, joint pain) reactions were observed, and serious adverse events were rare. These findings are consistent with known adverse events after receipt of first booster doses and with the existing body of evidence that mRNA COVID-19 vaccines are safe.
Hause AM, Baggs J, Marquez P, Abara WE, Baumblatt JG, Thompson D, Su JR, Myers TR, Gee J, Shimabukuro TT, Shay DK. Safety Monitoring of COVID-19 mRNA Vaccine First Booster Doses Among Persons Aged ≥12 Years with Presumed Immunocompromise Status — United States, January 12, 2022–March 28, 2022.. MMWR Morb Mortal Wkly Rep. 2022 Jul 15; 71(28);899–903.
Immunocompromised people are at risk for severe COVID-19 disease, and additional doses of COVID-19 vaccine are recommended for this population. To characterize the safety of first booster doses among immunocompromised persons ages 12 years and older, CDC reviewed adverse events (AEs) reported to V-safe and the Vaccine Adverse Event Reporting System (VAERS) during the week after receipt of an mRNA COVID-19 first booster dose (fourth dose administered ≥ 3 months after the third) during January 12, 2022–March 28, 2022. Safety data identified no unusual or unexpected patterns of AEs. Mild to moderate reactions, such as injection site pain, fatigue, headache, and muscle pain following a booster dose were similar to those among non-immunocompromised people. Local and systemic reactions were less common following dose 4 compared to dose 3. These findings support evidence that mRNA COVID-19 vaccines are safe for immunocompromised people.
Hause AM, Shay DK, Klein NP, Abara WE, Baggs J, Cortese MM, Fireman B, Gee J, Glanz JM, Goddard K, Hanson KE, Hugueley B, Kenigsberg T, Kharbanda EO, Lewin B, Lewis N, Marquez P, Myers T, Naleway A, Nelson JC, Su JR, Thompson D, Olubajo B, Oster ME, Weintraub ES, Williams JTB, Yousaf AR, Zerbo O, Zhang B, Shimabukuro TT. Safety of COVID-19 Vaccination in United States Children Ages 5 to 11 Years. Pediatrics. 2022 Jul 14. https://doi.org/10.1542/peds.2022-057313.
This study, published July 2022, reviewed adverse events observed following the Pfizer two-dose vaccine administered to children ages 5–11 years and found mild-to-moderate events within the first day or two of vaccination. Researchers analyzed data from three U.S. safety monitoring systems during four months of vaccine administration among children ages 5–11 years to provide insight on adverse events. Among 48,795 children ages 5–11 years enrolled in V-safe—a web-based tool that uses text messages, emails, and web surveys to provide personalized health check-ins for people after receiving a new vaccine—most reported events were mild to moderate, were most frequently reported the day after vaccination, and were more common after the second dose. The most common events reported were injection site pain, fatigue, headache, fever, and muscle soreness. The study also evaluated data from the Vaccine Adverse Events Reporting System (VAERS), the national spontaneous reporting system co-managed by CDC and the U.S. Food and Drug Administration, and the Vaccine Safety Datalink (VSD), an active surveillance system that monitors electronic health records for pre-specified events including myocarditis. VAERS received 7,578 adverse event reports; 97% were non-serious. Reviewing 194 serious VAERS reports, 15 myocarditis cases were verified; 8 occurred in males after dose 2. In VSD, no safety signals were detected in weekly sequential monitoring after administration of 726,820 doses. The authors concluded that the vaccine is safe for children ages 5–11 years and that adverse events are usually clinically mild and resolve quickly.
Hause AM, Zhang B, Yue X, Marquez P, Myers TR, Parker C, Gee J, Su J, Shimabukuro TT, Shay DK. Reactogenicity of Simultaneous COVID-19 mRNA Booster and Influenza Vaccination in the US. JAMA Netw Open 2022 Jul 1;5(7):e2222241.doi: 10.1001/jamanetworkopen.2022.22241.
A review of vaccine safety data from September 22, 2021, through January 16, 2022, looked at reported reactions following vaccination with both influenza (flu) and an mRNA-based COVID-19 booster dose (third dose administered ≥ 5 months after second dose) during the same healthcare visit. The review found that people who received a booster and flu vaccine simultaneously were slightly more likely to report systemic reactions (i.e., headache, fatigue, and muscle pain) than people who received just the COVID-19 booster. Data were collected and reviewed from V-safe, a web-based tool that uses text messages, emails, and web surveys to provide personalized health check-ins for people after receiving a new vaccine.
Rosenblum HG, Gee J, Liu R, Marquez PL, Zhang B, Strid P, Abara WE, McNeil MM, Myers TR, Hause AM, Su JR, Markowitz LE, Shimabukuro TT, Shay DK. Safety of mRNA vaccines administered during the initial 6 months of the US COVID-19 vaccination programme: an observational study of reports to the Vaccine Adverse Event Reporting System and v-safe. Lancet Infect Dis. 2022 Mar 7; S1473-3099(22)00054-8. Online ahead of print.
In a comprehensive analysis of mRNA COVID-19 vaccine data (i.e., Pfizer-BioNTech and Moderna), published June 2022, CDC scientists reviewed 6 months of safety data from the Vaccine Adverse Event Reporting System (VAERS), a passive vaccine safety surveillance system co-managed by CDC and the U.S. Food and Drug Administration (FDA), and V-safe, a web-based tool that uses text messages, emails, and web surveys to provide personalized health check-ins for people after receiving a new vaccine. During December 14, 2020, through June 14, 2021, more than 298 million doses of mRNA COVID-19 vaccine were administered. The review found that most reported reactions—such as headache, fatigue, and soreness at the injection site—were mild and short in duration and most reported adverse events were not serious (did not require hospitalization or cause disability, life-threatening illness, or death). These findings reinforce evidence that mRNA COVID-19 vaccines are safe and could reassure those who might be hesitant to get an mRNA vaccine because of safety concerns.
Hause AM, Baggs J, Marquez P, Abara WE, Olubajo B, Myers TR, Su JR, Thompson D, Gee J, Shimabukuro TT, Shay DK. Safety Monitoring of COVID-19 Vaccine Booster Doses Among Persons Aged 12–17 Years — United States, December 9, 2021–February 20, 2022. MMWR Morb Mortal Wkly Rep. 2022 Mar 1;71(9);347–351.
CDC reviewed safety data for a third dose of Pfizer-BioNTech COVID-19 vaccine administered ≥ 5 months after the second dose among adolescents ages 12–17 years. This review, published March 2022, identified no unusual or unexpected patterns of adverse events. Data from V-safe and the Vaccine Adverse Event Reporting System were used to characterize adverse events reported among this age group. Reactions such as injection site pain, fatigue, headache, and muscle pain following dose 3 vaccinations were mostly mild to moderate in severity and were most frequently reported the day after vaccination. Myocarditis was less frequently reported following a third dose than a second dose. Parents should be advised that local and systemic reactions are expected among adolescents following Pfizer-BioNTech vaccine dose 3 and that serious adverse events, including myocarditis, are rare.
Hause AM, Baggs J, Marquez P, Myers TR, Su JR, Blanc PG, Gwira Baumblatt JA, Woo EJ, Gee J, Shimabukuro TT, Shay DK. Safety Monitoring of COVID-19 Vaccine Booster Doses Among Adults — United States, September 22, 2021–February 6, 2022. MMWR Morb Mortal Wkly Rep. 2022 Feb 18; 71(7);249–254.
In this February 2022 report, CDC reviewed the safety of a third dose of mRNA COVID-19 vaccine administered ≥ 5 months after the second dose. Safety data on adults ages 18 and older from V-safe and the Vaccine Adverse Event Reporting System showed no unexpected patterns of adverse events and found that for people who received the same mRNA COVID-19 vaccine for dose 3 as they received for doses 1 and 2, local and systemic reactions (such as pain, fatigue, and headache) were less frequently reported after dose 3 than after dose 2. Myocarditis was rarely reported following mRNA COVID-19 vaccine dose 3.
Hause AM, Baggs J, Marquez P, Myers TR, Gee J, Su JR, Zhang B, Thompson D, Shimabukuro TT, Shay DK. COVID-19 Vaccine Safety in Children Ages 5-11 years — United States, November 3-December 19, 2021. MMWR Morb Mort Wkly Rep. 2021 Dec 31:70(5152);1755-1760.
On October 29, 2021, the FDA expanded emergency use authorization (EUA) for the Pfizer-BioNTech COVID-19 vaccine to include children ages 5-11 years. Once the EUA was in place, researchers began reviewing vaccine safety data for this age group, collected through the Vaccine Adverse Event Reporting System (VAERS) and v-safe. From November 3 through December 19, 2021, around 8.7 million doses of Pfizer vaccine were administered to children ages 5-11 years. During that time, VAERS received 4,249 reports of adverse events following vaccination for children in that age group, 98% of which were non-serious. There were 11 verified cases of myocarditis. Of the over 42,000 children enrolled in v-safe, 70% recorded a second dose. Local reactions (symptoms around the injection site) and systemic reactions (fever, headache, fatigue) following dose 2 of Pfizer vaccination among this age group were reported less frequently than reactions reported among children ages 12-15 years. The initial safety findings showed no unusual patterns of adverse events and that the benefits of COVID-19 vaccination continue to outweigh the risks. CDC and FDA will continue to monitor COVID-19 vaccine safety, communicate findings, and use vaccine safety data to inform vaccination recommendations.
Moro PL, Panagiotakopoulos L, Oduyebo T, Olson CK, Myers T. Monitoring the safety of COVID-19 vaccines in pregnancy in the US. Human Vaccines & Immunotherapies. 2021 Nov 10. doi.org/10.1080/21645515.2021.1984132.
Chapin-Bardales J, Myers T, Gee J, Shay DK, Marquez P, Baggs J, Zhang B, Licata C, Shimabukuro TT. Reactogenicity within 2 weeks after mRNA COVID-19 vaccines: Findings from the CDC v-safe surveillance system. Vaccine. 2021 Nov 26;39(48):7066-7073. Epub 2021 Oct 16.
In this review of v-safe vaccine safety data, researchers analyzed surveys of people who received their mRNA vaccine from December 14, 2020, through March 14, 2021. V-safe is a vaccine safety monitoring system that uses text messages and web surveys to collect information on health impacts reported after receipt of COVID-19 vaccines. During this time period, more than 4.7 million participants received one dose of an mRNA vaccine (Pfizer-BioNTech or Moderna), and over 2.9 million received a second dose. Most participants reported either a local reaction at the injection site (68.5% after dose 1; 72.9% after dose 2) or a systemic reaction, such as fever, headache, muscle ache and fatigue (50.6% after dose 1; 69.5% after dose 2). Researchers found that these side effects were reported more frequently among those who received Moderna than those who received Pfizer-BioNTech. An analysis of surveys reported on day 14 after vaccination indicated that new or worsening local and systemic reactions were uncommon during the second week following both dose 1 and dose 2. CDC will continue to closely monitor the safety of COVID-19 vaccines.
Hause AM, Baggs J, Gee J, Marquez P, Myers TR, Shimabukuro TT, Shay DK. Safety Monitoring of an Additional Dose of COVID-19 Vaccine — United States, August 12-September 19, 2021 MMWR Morb Mortal Wkly Rep. epub 2021 Sep 28.
On August 12, 2021, the Food and Drug Administration (FDA) expanded the Emergency Use Authorizations for Pfizer-BioNTech and Moderna (mRNA) COVID-19 vaccines to include an additional dose following the 2-dose vaccination series to those with compromised immune systems. From August 12 through September 19, over 22,000 v-safe enrollees reported an additional COVID-19 dose after completing the primary 2-dose mRNA vaccination series, most with the same vaccine. Among those who completed surveys for all 3 doses, local reactions (like pain or swelling where the shot was given) were reported slightly more after dose 3 compared with after dose 2 (79% vs. 78%), while reported systemic reactions (tiredness, headache) were slightly less common after dose 3 (74% vs. 77%). These side effects were mostly mild to moderate and short-lived. These findings did not show unexpected patterns of adverse events following an additional dose of COVID-19 vaccines. CDC will continue to monitor the safety of additional doses of COVID-19 vaccines and provide data to guide recommendations and protect the public’s health.
Hause AM, Gee J, Baggs J, Abara WE, Marquez P, Thompson D, Su JR, Licata C, Rosenblum HG, Myers TR, Shimabukuro TT, Shay DK. COVID-19 Vaccine Safety in Adolescents—United States, December 14, 2020—July 16, 2021. MMWR Morb Mortal Wkly Rep. 2021 Jul 30.
As of July 2021, Pfizer-BioNTech COVID-19 Vaccine (Pfizer-BioNTech) is the only COVID-19 vaccine authorized for use in adolescents (people aged 12–17 years). To evaluate the safety of Pfizer-BioNTech in adolescents, researchers reviewed data collected from VAERS and v-safe between December 14, 2020 through July 16, 2021. Over 8.9 million Pfizer-BioNTech doses were administered to adolescents ages 12-17. VAERS received 9,246 reports of adverse events in adolescents; over 90% of reports were non-serious. Myocarditis was reported in 4.3% (397) of all VAERS reports. Of the 129,000 adolescents who enrolled in v-safe, the most frequently reported side effects included injection site pain, fatigue, headache, and weakness. With the exception of myocarditis, the safety findings were similar to what was observed during preauthorization trials. CDC and FDA are actively monitoring the safety of COVID-19 vaccines. Serious adverse events after COVID-19 vaccination are rare, and CDC continues to recommend everyone 12 years and older get vaccinated as soon as possible to help protect against COVID-19.
Hause AM, Gee J, Baggs J, Abara WE, Marquez P, Thompson D, Su JR, Licata C, Rosenblum HG, Myers TR, Shimabukuro TT, Shay DK. COVID-19 Vaccine Safety in Adolescents—United States, December 14, 2020—July 16, 2021. MMWR Morb Mortal Wkly Rep. 2021 Jul 30.
As of July 2021, Pfizer-BioNTech COVID-19 Vaccine (Pfizer-BioNTech) is the only COVID-19 vaccine authorized for use in adolescents (people aged 12–17 years). To evaluate the safety of Pfizer-BioNTech in adolescents, researchers reviewed data collected from VAERS and v-safe between December 14, 2020 through July 16, 2021. Over 8.9 million Pfizer-BioNTech doses were administered to adolescents ages 12-17. VAERS received 9,246 reports of adverse events in adolescents; over 90% of reports were non-serious. Myocarditis was reported in 4.3% (397) of all VAERS reports. Of the 129,000 adolescents who enrolled in v-safe, the most frequently reported side effects included injection site pain, fatigue, headache, and weakness. With the exception of myocarditis, the safety findings were similar to what was observed during preauthorization trials. CDC and FDA are actively monitoring the safety of COVID-19 vaccines. Serious adverse events after COVID-19 vaccination are rare, and CDC continues to recommend everyone 12 years and older get vaccinated as soon as possible to help protect against COVID-19.
Shay DK, Gee J, Su JR, Myers TR, Marquez P, Liu R, Zhang B, Licata C, Clark TA, Shimabukuro TT. Safety Monitoring of the Janssen (Johnson & Johnson) COVID-19 Vaccine — United States, March-April 2021. MMWR Morb Mortal Wkly Rep. 2021 April 30. Epub ahead of print.
Johnson & Johnson’s Janssen COVID-19 vaccine was authorized by FDA for emergency use on February 27, 2021. By April 21, nearly 8 million doses of the Janssen COVID-19 vaccine had been administered. CDC researchers reviewed safety monitoring data from VAERS and the v-safe after-vaccination health checker, and found 97% of reported reactions after vaccination, such as headache, fever, chills, injection site pain, and fatigue, were nonserious and consistent with clinical trials data. CDC and FDA issued a pause of the Janssen vaccine April 12–23, 2021, after 6 cases of cerebral venous sinus thrombosis (CVST), a serious condition that involves blood clots in the brain, were identified in VAERS. By April 25, a total of 17 thrombotic (blood clots) events with thrombocytopenia (low platelet counts) were reported to VAERS, including 3 thrombotic events not occurring in the brain. CDC and FDA continue to monitor the safety of COVID-19 vaccines, analyzing the risks and benefits of continued use.
Shimabukuro TT, Kim SY, Myers TR, Moro PL, Oduyebo T, Panagiotakopoulos L, Marquez PL, Olson CK, Liu T, Chang KT, Ellington SR, Burke VK, Smoots AN, Green CJ, Licata C, Zhang BC, Alimchandani M, Mba-Jonas A, Martin SW, Gee JM, Meaney-Delman DM. Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons N Engl J Med 2021 April 21. DOI: 10.1056/NEJMoa2104983 Epub ahead of print.
Pregnant people were not included in the messenger RNA (mRNA) COVID-19 vaccine clinical trials. Because of the increased risk of severe illness from COVID-19, CDC has provided guidance to pregnant people who may want to get a COVID-19 vaccine. The safety of mRNA vaccines in pregnant people is monitored through 3 systems: v-safe after vaccination health checker, the v-safe pregnancy registry and VAERS. From December 14, 2020 through February 28, 2021, 35,691 v-safe participants ages 16 to 54 identified as pregnant. Injection site pain was commonly reported. Of those, 3,958 enrolled in the v-safe pregnancy registry: 827 completed pregnancy; 712 (86.1%) had live births, with most vaccinations completed in the 3rd trimester. In the VAERS reports following mRNA vaccinations, 155 (70.1%) were nonpregnancy specific; 66 (29.9%) were pregnancy and neonatal specific events. The analysis of v-safe and VAERS data did not show any safety concerns among pregnant persons who received mRNA COVID-19 vaccines.
Chapin-Bardales J, Gee J, Myers T. Reactogenicity Following Receipt of mRNA-Based COVID-19 Vaccines JAMA Insights 2021 April 5. doi:10.1001/jama.2021.5374 Epub ahead of print.
CDC created v-safe, a smartphone-based tool, to monitor in near-real time the safety of COVID-19 vaccines authorized by FDA for emergency use. V-safe uses text messaging and web surveys to provide personalized health check-ins after COVID-19 vaccination. Researchers reviewed data collected from v-safe from December 14, 2020 to February 28, 2021, including side effects and reactions to the mRNA COVID-19 vaccines. Over 3.6 million v-safe participants completed at least one health check-in after the first dose and over 1.9 million after the second dose. Injection site pain was commonly reported after first (70%) and second doses (75%) of either mRNA vaccine. Systemic reactions, such as fatigue, headache, muscle pain, chills, fever, and joint pain were the top symptoms reported by participants after the first mRNA vaccine dose. These reports increased substantially after the second dose among both mRNA vaccines. People aged 65 years and older reported fewer reactions than younger people. While v-safe is voluntary and includes less than 10% of people vaccinated, reported reactions to the mRNA vaccines were consistent with results observed in clinical trials.</p
Gee J, Marquez P, Su J, Calvert GM, Liu R, Myers T, Nair N, Martin S, Clark T, Markowitz L, Lindsey N, Zhang B, Licata C, Jazwa A, Sotir M, Shimabukuro T. First Month of COVID-19 Vaccine Safety Monitoring — United States, December 14, 2020-January 13, 2021 MMWR Morb Mortal Wkly Rep. 2021 Feb 26;70;283-288.
The U.S. FDA authorized two COVID-19 vaccines for emergency use in December 2020: Pfizer-BioNTech and Moderna. During clinical trials, there were reports of local reactions where the shot was given, and systemic reactions affecting other parts of the body. Safety monitoring for these vaccines has been the most intense and comprehensive in U.S. history. From December 14, 2020 through January 13, 2021, almost 14 million vaccine doses were distributed. During that time, over 1.6 million vaccine recipients enrolled in v-safe, and VAERS received 6,994 reports of adverse events following vaccination. About 91% of VAERS reports were non-serious; commonly reported symptoms included headache (22.4%), fatigue (16.5%) and dizziness (16.5%). V-safe enrollees reported similar local and systemic reactions. While deaths were reported to VAERS, available documentation did not suggest a causal link between the vaccine and death. Overall, no unusual or unexpected reporting patterns were detected.