In December, 2019, a novel coronavirus, now known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),D burst onto the world scene. After rapid early spread, a pandemic was declared; efforts to evaluate the safety and efficacy of SARS-CoV-2 vaccines were launched immediately in hopes of limiting the spread, severity of illness, and death associated with COVID.1 Trials were conducted in an expedited manner proceeding through phase 1, phase 2, and phase 3 testing at an unprecedented pace. COVID vaccines were established to be safe and highly efficacious in clinical trials, and Food and Drug Administration (FDA) emergency use authorization (EUA) was granted in late 2020.2–8 With billions of doses having been administered worldwide, COVID vaccines have been proven safe and effective. As an organization, the American Medical Society for Sports Medicine (AMSSM) supports COVID vaccination for all eligible athletes without contraindication(s).4
Although the world has been faced with pandemics for more than a century, the negative impact on humanity and sport regarding the COVID-19 virus continues. The coronavirus pandemic has been an unexpected, idiosyncratic transition affecting sporting organizations, institutions, athletes, and their loved ones. How to effectively manage sport participation in the pandemic has been a challenge to the sports medicine community. While vaccination for COVID has been promising for the return to sports, the number of challenges that remain is overwhelming including a percentage of the athletic population that remains skeptical of receiving vaccination.
Development of Vaccine
Vaccination is believed to be the 20th century's most triumphant method of infectious disease prevention and eradication. Despite some public sentiment, COVID vaccine research has been ongoing for decades. This existing research paved the way for the rapid development of mRNA and modified DNA vaccines against this novel SARS-CoV-2.4,8
Importance of Vaccination for Athletes
Vaccination is considered the fastest, safest, and most efficient way to bring this crisis to an end.4–7,9,10 With every day that passes, the human and financial costs of the pandemic, both direct and indirect, continue to soar. Potential benefits to becoming fully immunized include but are not limited to the following:1–10
- Safer resumption of activities performed before the pandemic including increased interactions with teammates, friends, and family
- Less game and practice time lost to outbreaks
- Increased opportunity for in-person school attendance
- Improved access to travel and other mass public events
- Reduced routine testing
- Decreased risk of infection, severe illness, and death for individuals and others in the community
- Reduced secondary conditions associated with social isolation and other pandemic-related concerns (mental, physical, and psychosocial well-being; food insecurity; financial hardship; health disparities; etc.)
Types of COVID Vaccines
COVID vaccines were developed using several different technologies, including the novel use of messenger RNA (mRNA). COVID vaccines currently in use under FDA EUA in the Unites States include mRNA and replication-defective viral vector vaccines, with protein subunit and live-attenuated vaccines still in preclinical development or clinical trials (Table 1).
TABLE 1. -
Vaccinations Granted EUA for the Prevention of COVID-19 by the United States FDA*
|BNT162b2 (Pfizer-BioNTech COVID vaccine)
||Individuals aged 12 years or older
||Two intramuscular doses of 0.3 mL each
||Given 3 wk (21 days) apart
|mRNA-1273 (Moderna COVID vaccine)
||Individuals aged 18 years or older
||Two intramuscular doses of 0.5 mL each
||Given 1 mo (28 days) apart
|Ad26.COV2.S (Janssen COVID vaccine)/“Johnson & Johnson”
||Individuals aged 18 years or older
||One intramuscular dose of 0.5 mL
Table assembled from published information.1,4,8–14
Altered Dosing Intervals
- The efficacy of administering vaccines outside of the recommended time frame is uncertain.4
- Athletes receiving a two-dose mRNA vaccine (BNT162b2 or mRNA-1273) should be given the second dose as close to the recommended interval as possible, but not earlier than recommended5,6
If the second dose is not given within the recommended time frame, it should be given as soon possible.8–10,12
- Twenty-one days for BNT162b2 (Pfizer) and 28 days for mRNA-1273 (Moderna)
Each vaccine series should be completed with the same vaccine initially used.5–10,12
- The Centers for Disease Control and Prevention (CDC) states the series does not need to be repeated if the second dose is given too early or given more than 6 weeks after the first dose.
For athletes who received a first dose of an mRNA vaccine but cannot receive either the mRNA vaccines for the second dose (eg, because of contraindications), Ad26.COV2.S can be given as long as there is not also a contraindication to Ad26.COV2.
- If an mRNA vaccine used for the first dose is temporarily unavailable at the time the second dose is due, the CDC recommends delaying the second dose until the same vaccine becomes available.
- If 2 different vaccine products are used to complete the series, no additional doses of either mRNA vaccine are recommended.
If SARS-CoV-2 infection is diagnosed after the first vaccine dose, the second dose should still be given. Vaccination administration is prohibited, however, if the athlete is acutely ill or in isolation.12–14
Additional and updated information regarding COVID vaccine administration errors and deviations are available.12,15
- The CDC suggests giving Ad26.COV2.S at least 28 days after the mRNA vaccine dose.7,12
Timing with Non-COVID Vaccines
Per the Advisory Committee on Immunization Practices, COVID vaccines may be administered with non-COVID vaccines without regard to timing.12
Serologic testing to confirm antibody response after vaccination and/or to determine infection before vaccination is not warranted.16
ADVICE TO ATHLETES BEFORE COVID VACCINATION
- Owing to uncertain impact on the host immune response to vaccination prophylactic use of analgesics or antipyretics (eg, nonsteroidal anti-inflammatory drugs or acetaminophen) before vaccine receipt is not recommended.17–18
- Although some side effects may occur, most are short-lived especially in comparison with actual illness or subsequent quarantine/isolation requirements if an athlete and/or teammate(s) were to become infected.16
- Delaying vaccination until sports/competition is complete is not appropriate.16
SPECIFIC ATHLETIC POPULATIONS
Athletes with a History of SARS-Cov-2 Infection
- The COVID vaccine is recommended for athletes with a history of SARS-CoV-2 infection if there is no medical contraindication to receiving the vaccine.12
Although studies are small and limited, the evidence suggests that those with prior SARS-CoV-2 infection mount substantially higher binding and neutralizing antibody responses to vaccination compared with SARS-CoV-2-naïve individuals.12
The athlete should be recovered from acute infection and meet criteria for discontinuation of isolation precautions before receiving the vaccine.19,20
Athletes who received monoclonal antibodies or convalescent plasma for COVID infection should delay vaccination for at least 90 days from the time of treatment.12,20
For athletes with a history of SARS-CoV-2 infection complicated by multisystem inflammatory syndrome, the decision to vaccinate should be individualized with clinical guidance following risk and benefit discussion with their medical home.12,21
Athletes should be counseled that individuals with a history of SARS-CoV-2 may be more likely to experience local and systemic adverse effects (eg, fevers, chills, myalgias, and fatigue) after a vaccine dose than SARS-CoV-2-naïve individuals, but this should not delay vaccination.21
- mRNA vaccines are preferred.
- Athletes without contraindications who have an immunocompromising condition or are taking immunosuppressive agents should still undergo COVID vaccination.22,23
- Athletes should discuss with their medical home if the timing of vaccination with immunosuppressive agent administration should be considered.22,23
Pregnant and Breast-Feeding Athletes
- While pregnancy and breast feeding are not contraindications to COVID vaccination, data are limited. The decision to vaccinate should be discussed with specialty clinicians and decided on an individual level.24
The youth athlete (7-18 years of age)
- Eligible children should undergo COVID vaccination, if not contraindicated, with a product authorized for use in the specific age group.5
- At the time of press, the only vaccine currently authorized for use younger than 18 years is the BNTb162b Pfizer/BioNTech vaccine.5,25,26
Contraindications for COVID Vaccination
- Severe allergic reaction (eg, anaphylaxis) to a previous COVID vaccine dose or to a component of the vaccine.12
- Allergic reaction of any severity (including hives) developing within 4 hours of a previous COVID vaccine.12
- Allergic reaction to polysorbate is not a contraindication to mRNA vaccines, but it is a contraindication to Ad26.COV2.S.12
- The CDC suggests that individuals with a syndrome of thrombosis and thrombocytopenia (such as heparin-induced thrombocytopenia) within the prior 90 days receive an mRNA vaccine rather than Ad26.COV2.S.12
REACTIONS TO THE COVID VACCINATION
Similar to any medical product, vaccines, although designed to protect from disease, can cause side effects. Clinicians and athletes should be aware that side effects of vaccination overlap with symptoms of COVID.27–42 Systemic reactions (eg, fever, chills, fatigue, and headache) that occur within the first day or 2 after vaccination and resolve within a day or 2 are most often consistent with a response to the vaccine. In the presence of respiratory symptoms or systemic symptoms that occur after the first couple days after vaccination or that do not resolve within several days, active SARS-CoV-2 infection should be suspected. In cases of suspected infection, the athlete should subsequently be tested and isolated.36
Common Local and Systemic Reactions
- Pain at the injection site, ipsilateral axillary lymph node enlargement, fever, fatigue, and headache.29
- BNT162b2 may be associated with slightly lower rates of local and systemic reactions compared with mRNA-127329
- Possibly because of other causes (vasovagal syncope).27,29
- More common among adolescents and young adults.36,37,40
- Monitoring is recommended for 15 to 30 minutes after COVID vaccination.36,37
Rare Adverse Reactions
- Anaphylaxis with mRNA vaccines27,31,36,37
- Thrombotic events with thrombocytopenia12,27,31,36,37
Venous thromboembolic events without thrombocytopenia (deep vein thrombosis or pulmonary embolism)12,27,36,37
- Associated with Ad26.COV2.S
Myocarditis and/or pericarditis32–34,37,38,40,44
- Associated with Ad26.COV2.S
- Although rare, pericarditis and myocarditis have been reported among recipients of mRNA vaccines. The chance of developing this heart condition is 6 times greater after infection compared with side effect of vaccination.
- Most symptoms are mild, however, and may include chest pain and shortness of breath within 21 days postvaccine.
- When concerned for postvaccination myocarditis and/or pericarditis, athletes should be closely monitored for any cardiopulmonary symptoms especially on exertion.
- When warranted, further evaluation should include electrocardiogelectrocardiogram, echo, and troponin-I. Cardiac magnetic resonance imaging remains the gold standard for diagnosis and should be considered when appropriate.
- More common in male adolescents and young adults who receive a mRNA vaccine,32,34,40 with the median age range for events being 24 to 30 years of age.
- Symptoms frequently resolve within 1 week of starting therapy.
Shoulder Injury Related to Vaccine Administration
Although shoulder injury related To vaccine administration is not specific to COVID vaccinations, there have been multiple case reports and systematic reviews reporting adhesive capsulitis and injury to the rotator cuff.28,35,39,42
Vaccine Administration Errors and Serious Adverse Events
Vaccine providers and manufactures are responsible for reporting vaccine administration errors and serious adverse events associated with vaccination to the Vaccine Adverse Event Reporting System (VAERS).15 VAERS is comanaged by the CDC and the US FDA.12
EXERCISE AND ITS EFFECTS ON THE COVID VACCINE
There is no evidence to suggest exercise decreases vaccine efficacy. Some studies suggest regular exercise may improve vaccine response.41
OVERCOMING VACCINE HESITANCY AMONG ATHLETES AND THE SPORTS COMMUNITY
The Importance of Overcoming Vaccine Hesitancy
- For the general population, it is clear that the benefits of COVID vaccination greatly outweigh any potential risks.45–50
- Although the young athlete population is at less risk of serious illness and death, the risk is not negligible and long-term effects of infection may inhibit future health and sports participation because of prolonged symptoms such as exercise intolerance and shortness of breath.47,49
- Broad vaccination coverage is needed to achieve herd immunity and slow community transmission.45–50
Reasons for Vaccine Hesitancy
- Studies have shown that most common reasons for reporting nonintent to receive vaccine were concerns about vaccine side effects and safety, effectiveness, as well as a lack of trust in the creation process.46,50
- Disparities between urban and rural communities in COVID vaccination coverage and access have impeded progress toward ending the pandemic.46,50
- COVID vaccine hesitancy seems to be more common among individuals younger than 60 years, who have lower levels of education, lower household income, rural residence, and lack of health insurance.46,50
- Completion of COVID vaccination was the lowest among Hispanic and Black persons.46,50
- Black people account for more than 50 percent of COVID infections and 70 percent of deaths, yet they have one of the lowest vaccination rates.46,50
- The rate of COVID infection among Hispanic people exceeds the number of completed vaccination coverage by more than 50%.46,50
Limiting Vaccine Hesitancy
- The sports medicine community should collaborate with sporting organizations, healthcare providers, pharmacies, employers, schools, local health departments, and other community partners to identify and address barriers to COVID vaccination.
- Providers should make direct recommendations for vaccination when appropriate.
- Athletic medical staff should identify concerns in their athletes and act to educate athletes and families on vaccine risks and benefits while dispelling misperceptions about the disease and the vaccine.
- More effort is needed to isolate and address potential barriers to access and improve vaccine acceptance, particularly among Hispanic and Black persons.
- Additional education and communication recommendations for providers are available.51
INCORPORATING THE VACCINATION INTO THE PREPARTICIPATION PHYSICAL EXAMINATION
As one of the most common reasons for an athlete to see a primary care physician either independently or as part of a health supervision visit, the preparticipation physical examination (PPE) is an opportune time to provide COVID vaccination.
General PPE Recommendations
- The fifth edition monograph of the PPE (PPE5) recommends that the evaluation be completed in the medical home where there is improved continuity of care and confidentiality with access to the full medical record.43
Group physicals are not recommended by the PPE5 and may not even be possible because of physical distancing guidelines.
The authors recognize that performing PPEs in the medical home and recommending no group PPEs may impose scheduling challenges for both healthcare providers and families. We also appreciate that these recommendations may limit access for athletes who rely on mass physicals for their screening examination.
- Most medical homes are already equipped to easily provide vaccination without any additional infrastructure or personnel required.
Use the PPE as an opportunity to identify and record the following information:
- If group physicals were to occur, however, we encourage working with local departments of health and hospital systems to create mass vaccination opportunities for both the initial and second shot if getting a two-dose vaccine.
- Prior SARS-CoV-2 infection?
- If so, when did the infection occur, what symptoms were experienced and for how long.
- Were diagnostic tests performed (eg, echocardiogram and chest x-ray)?
- Was there a need for any physician-directed treatment or hospitalization?
- Presence of postinfection sequelae (eg, myocarditis)?
- Did the athlete achieve full recovery and return to play?
- Is the athlete experiencing persistent symptoms? If so, what symptoms?
- Is the athlete experiencing new symptoms with exercise (especially chest pain or excessive shortness of breath)?
- COVID vaccination status?
- Which vaccine was received? Dates of administration? Reaction(s) to vaccination?
COVID Vaccine Administration During the PPE
- Be aware of and abide by parental consent laws of your state regarding vaccine administration.
- Follow all manufacturer guidelines regarding storage, transportation, and maintenance of vaccines.
- Report vaccine administration to the state's immunization information system.
- Consider who can give vaccinations (eg, some states allow certified athletic trainers)
- Document all information in the medical record including lot.
- After vaccination administration
- Monitor of most athletes for 15 minutes postvaccination is recommended
- Monitor athletes for 30 minutes if they have history of
- Immediate reaction to any vaccine or injectable therapy
- Contraindication to other vaccine types
- History of anaphylaxis because of any cause
- Provide athlete with complete proof of the vaccination record.
POSTVACCINE RECOMMENDATIONS FOR ATHLETES
- Consider a temporary reduction in training load in the first 48 to 72 hours postvaccine injection, particularly after the second dose.42
- After receipt of a completed vaccination, ensure that the athlete knows that they are considered fully vaccinated after 2 weeks have elapsed.
- Continue universal precautions and follow updated CDC guidelines
- Symptoms consistent with COVID should prompt testing, regardless of the vaccination status.
- COVID vaccine is not 100 percent effective. Breakthrough cases are rare but have been reported as are infections from more recent and virulent strains/variants (eg, the Delta variant).
- Booster vaccination to prolong and broaden immunity against these variants is currently being investigated.
Widespread vaccination against COVID is necessary to reduce the disease burden of the SARS-CoV-2 pandemic and for the return to normal sports activities. Athletes who qualify for vaccination should be urged to become vaccinated as quickly as possible.
1. World Health Organization. Director-General's remarks at the media briefing on 2019-nCoV on 11 February 2020. Available at: http://www.who.int/dg/speeches/detail/who-director-general-s-remarks-at-the-media-briefing-on-2019-ncov-on-11-february-2020
. Accessed February 12, 2020.
2. Lin JT, Zhang JS, Su N, et al. Safety and immunogenicity from a phase I trial of inactivated severe acute respiratory syndrome coronavirus vaccine. Antivir Ther. 2007;12:1107–1113.
3. Martin JE, Louder MK, Holman LA, et al. A SARS DNA vaccine induces neutralizing antibody and cellular immune responses in healthy adults in a Phase I clinical trial. Vaccine. 2008;26:6338–6343.
4. The College of Physicians of Philadelphia. The history of vaccines: vaccine development, testing, and regulation. Available at: https://www.historyofvaccines.org/content/articles/vaccine-development-testing-and-regulation
. Accessed October 20, 2020.
5. US Food & Drug Administration.Emergency use authorization (EUA) of the Pfizer-Biontech covid-19 vaccine to prevent coronavirus disease 2019 (covid-19). Available at: https://www.fda.gov/media/144413/download
. Accessed December 29, 2020.
6. US Food & Drug Administration. Emergency use authorization (EUA) of the Moderna covid-19 vaccine to prevent coronavirus disease 2019 (covid-19) US Food & Drug Administration. Available at: https://www.fda.gov/media/144637/download?utm_medium=email&utm_source=govdelivery
. Accessed December 18, 2020.
7. US Food & Drug Administration. Emergency use authorization (EUA) of the Janssen covid-19 vaccine to prevent coronavirus disease 2019 (covid-19). Available at: https://www.fda.gov/media/146304/download
. Accessed March 1, 2021.
8. World Health Organization. DRAFT landscape of COVID-19 candidate vaccines – 11 April 2020. Available at: https://www.who.int/blueprint/priority-diseases/key-action/Novel_Coronavirus_Landscape_nCoV_11April2020.PDF?ua=1
. Accessed October 20, 2020.
9. Kaur SP, Gupta V. COVID-19 Vaccine: a comprehensive status report. Virus Res. 2020;288:198114.
10. Krammer F. SARS-CoV-2 vaccines in development. Nature. 2020;586:516–527.
11. Borobia AM, Carcas AJ, Pérez-Olmeda M, et al. Immunogenicity and reactogenicity of BNT162b2 booster in ChAdOx1-S-primed participants (CombiVacS): a multicentre, open-label, randomised, controlled, phase 2 trial. Lancet. 2021;398:121–130.
12. Centers for Disease Control and Prevention. Interim clinical considerations for use of COVID-19 vaccines currently authorized in the United States. Available at: https://www.cdc.gov/vaccines/covid-19/clinical-considerations/covid-19-vaccines-us.html
. Accessed July 23, 2021.
13. Normark J, Vikström L, Gwon YD, et al. Heterologous ChAdOx1 nCoV-19 and mRNA-1273 vaccination. N Engl J Med. 2021;385:1049–1051.
14. Shaw RH, Stuart A, Greenland M, et al. Heterologous prime-boost COVID-19 vaccination: initial reactogenicity data. Lancet. 2021;397:2043–2046.
15. Centers for Disease Control and Prevention. COVID-19 vaccine administration - errors and deviation. Available at: https://www.cdc.gov/vaccines/covid-19/downloads/covid19-vaccine-errors-deviations.pdf
. Accessed June 8, 2021.
16. Infectious Disease Society of America. COVID-19 prioritization of diagnostic testing. Available at: https://www.idsociety.org/globalassets/idsa/public-health/covid-19-prioritization-of-dx-testing.pdf
. Accessed March 22, 2020.
17. Doedée AM, Boland GJ, Pennings JL, et al. Effects of prophylactic and therapeutic paracetamol treatment during vaccination on hepatitis B antibody levels in adults: two open-label, randomized controlled trials. Plos One. 2014;9:e98175.
18. Prymula R, Siegrist CA, Chlibek R, et al. Effect of prophylactic paracetamol administration at time of vaccination on febrile reactions and antibody responses in children: two open-label, randomised controlled trials. Lancet. 2009;374:1339–1350.
19. Krammer F, Srivastava K, Alshammary H, et al. Antibody responses in seropositive persons after a single dose of SARS-CoV-2 mRNA vaccine. N Engl J Med. 2021;384:1372–1374.
20. Manisty C, Otter AD, Treibel TA, et al. Antibody response to first BNT162b2 dose in previously SARS-CoV-2-infected individuals. Lancet. 2021;397:1057–1058.
21. Prendecki M, Clarke C, Brown J, et al. Effect of previous SARS-CoV-2 infection on humoral and T-cell responses to single-dose BNT162b2 vaccine. Lancet. 2021;397:1178–1181.
22. Centers for Disease Control and Prevention. Updated healthcare infection prevention and Control recommendations in response to COVID-19 vaccination. Available at: https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-after-vaccination.html
. Accessed May 5, 2021.
23. Oliver S. Data and clinical considerations for additional doses in immunocompromised people. Presented at Advisory Committee on Immunization Practices in Atlanta, GA on Jul 22, 2021. Available at: https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-07/07-COVID-Oliver-508.pdf
. Accessed on July 23, 2021.
24. Shimabukuro TT, Kim SY, Myers TR, et al. Preliminary findings of mRNA covid-19 vaccine safety in pregnant persons. N Engl J Med. 2021;384:2273–2282.
25. Anderson EJ, Campbell JD, Creech CB, et al. Warp speed for coronavirus disease 2019 (COVID-19) vaccines: why are children stuck in neutral?. Clin Infect Dis. 2021;73:336–340.
26. Centers for Disease Control and Prevention. Vaccines for children program (VFC). Available at: https://www.cdc.gov/vaccines/programs/vfc/
. Accessed November 5. 2020.
27. Anand P, Stahel VP. Review the safety of Covid-19 mRNA vaccines: a review. Patient Saf Surg. 2021;15:20.
28. Cagle PJ Jr.. Shoulder injury after vaccination: a systematic review. Rev Bras Ortop (Sao Paulo). 2021;56:299–306.
29. Centers for Disease Control and Prevention. Syncope after vaccination—United States, January 2005-July 2007. MMWR Morb Mortal Wkly Rep. 2008;57:457–460.
30. Centers for Disease Control and Prevention. Vaccine safety datalink (VSD). Available at: https://www.cdc.gov/vaccinesafety/ensuringsafety/monitoring/vsd/index.html
. Accessed November 5. 2020.
31. Chapin-Bardales J, Gee J, Myers T. Reactogenicity following receipt of mRNA-based COVID-19 vaccines. JAMA. 2021;325:2201–2202.
32. Drezner JA, Heinz WM, Asif IM, et al. Cardiopulmonary considerations for high school student-athletes during the COVID-19 pandemic: NFHS-AMSSM guidance statement. Sports Health. 2020;12:459–461.
33. Erickson CC, Salerno JC, Berger S, et al. Sudden death in the young: information for the primary care provider. Pediatrics. 2021;148:e2021052044
34. Gargano JW, Wallace M, Hadler SC, et al. Use of mRNA COVID-19 vaccine after reports of myocarditis among vaccine recipients: update from the Advisory Committee on Immunization Practices—United States, June 2021. MMWR Morb Mortal Wkly Rep. 2021;70:977–982.
35. Jotwani V, Narducci DM. Pain in right shoulder · recent influenza vaccination · history of hypertension and myocardial infarction Dx?. J Fam Pract. 2019;68:44–46.
36. Kaur RJ, Dutta S, Bhardwaj P, et al. Adverse events reported from COVID-19 vaccine trials: a systematic review. Indian J Clin Biochem. 2021;36:1–13.
37. Majeed A, Papaluca M, Molokhia M. Assessing the long-term safety and efficacy of COVID-19 vaccines. J R Soc Med. 2021;114:337–340.
38. Moulson N, Petek BJ, Drezner JA, et al. SARS-CoV-2 cardiac involvement in young competitive athletes. Circulation. 2021;144:256–266.
39. Shahbaz M, Blanc PD, Domeracki SJ, et al. Shoulder injury related to vaccine administration (SIRVA): an occupational case report. Workplace Health Saf. 2019;67:501–505.
40. Shay DK, Shimabukuro TT, DeStefano F. Myocarditis occurring after immunization with mRNA-based COVID-19 vaccines. JAMA Cardiol. 2021;6:1115–1117.
41. Valenzuela PL, Simpson RJ, Castillo-García A, et al. Physical activity: a coadjuvant treatment to COVID-19 vaccination Brain Behav Immun. 2021;94:1–3.
42. Waninger KN, Slenker N. Frozen shoulder related to influenza vaccine administration. Clin J Sport Med. 2021 [epub ahead of print].
43. Bernhardt DT, Roberts WO. PPE Preparticiption Physical Examination. IL: American Academy of Pediatrics. Itasca; 2019.
44. Singer ME, Taub IB, Kaleber DC. Risk of myocarditis from COVID-19 infection in people under age 20: a population-based analysis. medRxiv—The Preprint Server for Health Science, 2021.
45. CDC COVID-19 Vaccine Breakthrough Case Investigations Team. COVID-19 vaccine breakthrough infections reported to CDC—United States, January 1-April 30, 2021. MMWR Morb Mortal Wkly Rep. 2021;70:792–793.
46. Daly M, Jones A, Robinson E. Public trust and willingness to vaccinate against COVID-19 in the US from October 14, 2020, to March 29, 2021. JAMA. 2021;325:2397–2399.
47. Hull JH, Schwellnus MP, Pyne DB, Shah A. COVID-19 vaccination in athletes: ready, set, go. Lancet Respir Med. 2021;9:455–456.
48. Kaplan RM, Milstein A. Influence of a COVID-19 vaccine's effectiveness and safety profile on vaccination acceikptance. Proc Natl Acad Sci USA. 2021;118:e2021726118.
49. Meyer T, Wolfarth B, Gärtner B. Recommendations for athletes to vaccinate against SARS-CoV-2. Deutsche Z für Sportmedizin/German J Sports Med. 2021;72:E1–E4.
50. Nguyen KH, Srivastav A, Razzaghi H, et al. COVID-19 vaccination intent, perceptions, and reasons for not vaccinating among groups prioritized for early vaccination—United States, September and December 2020. MMWR Morb Mortal Wkly Rep. 2021;70:217–222.
51. Centers for Disease Control and Prevention. Communication resources. Available at: https://www.cdc.gov/coronavirus/2019-ncov/communication/index.html
. Accessed June 8, 2021.