Abstract
SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a novel coronavirus that causes a spectrum of clinical manifestations known as COVID-19 (coronavirus disease 2019). Airborne spread of the virus has led to a global pandemic, with serious health threats to the elderly, immunocompromised individuals, and those with comorbid medical conditions.2,5,6 Emerging evidence also suggests that SARS-CoV-2 infection may cause myocardial injury and latent myocarditis in patients with mild or no symptoms, raising concern that athletes afflicted by COVID-19 may be at higher risk of arrhythmias or even sudden cardiac arrest.1,3,4
Social distancing and facial coverings are the primary methods used to mitigate spread of the virus. On March 23, 2020, Washington State Governor Jay Inslee implemented the “Stay Home, Stay Healthy” order, canceling all group gatherings, including youth sports. As stay-at-home restrictions were lifted, public health guidelines have allowed for outdoor recreation in groups of 5 or less during phase 2 of Governor Inslee’s reopening plan.
Youth sports play an integral role in the physical and mental well-being of children and adolescents. Seattle United and Washington Youth Soccer led the development of safety and hygiene protocols to foster a safe return to small group, physically distanced training as allowed within county public health regulations. Determining the effectiveness of these measures to prevent new infections between teammates, coaches, and staff is vital to informing future public health guidelines.
Objective
The objective of this study was to monitor the prevalence of new infections within the Seattle United youth soccer club during small group, physically distanced training with comparison to the prevalence of infections within King County during the same time period.
Methods
Seattle United is the largest youth soccer club in Washington State with children and adolescents aged 7 to 18 years old participating. The Seattle United coaching directors in conjunction with a medical advisory committee developed safety, hygiene, and physical distancing recommendations for small group training. Players, families, and coaches were educated on the protocols using a multimedia approach, including email communications, information sheets, coach-led video tutorials, webinars, and podcasts. Teams were divided into small groups of 5 or less. During the first 2 weeks of training, practices were limited to 1 team per soccer field with pods of up to 5 players divided into 4 field quadrants. After 2 weeks of training, 2 teams were allowed to practice on a single soccer field, with small group pods spaced into 8 field sections. Players were required to wear a mask to and from training, but use of a mask during exercise was optional. Players were always physically distanced from each other during training by a minimum of 6 feet at all times. Coaching directors designed training sessions focused on individual skill development, passing, receiving, and fitness while adhering to distancing guidelines. No group gatherings during or after practice were allowed, and hand sanitizer was encouraged before and after training.
Seattle United uses TeamSnap to track player attendance. Attendance was also taken at practice by the coach and the reason for a player absence noted. Players and families were asked to check daily for any symptoms of illness and were instructed not to attend practice if feeling ill or a household member was ill. Team practice schedules and player attendance were monitored daily, and families were contacted by email if the reason for a player absence was unknown. If a player missed practice due to illness, the family was contacted by email and/or phone to clarify the circumstances and provide guidance for COVID-19 diagnostic testing if indicated. All individuals with symptoms consistent with possible COVID-19 were encouraged to be tested. Any player or family exposed to someone with confirmed or suspected COVID-19 were provided contact tracing and quarantine guidance based on public health recommendations.
Surveillance continued for a total of 6 weeks (June 29, 2020, through August 9, 2020). All confirmed new cases of COVID-19 in a player, coach, or household member were tracked. As a precaution, if a player tested positive for SARS-CoV-2 and had participated at practice within 48 hours of the date of his or her test, the player’s small group pod was tested and quarantined. Because these were considered low-risk exposures, players were allowed back at practice once a negative result was confirmed.
The prevalence of COVID-19 in the community (daily new cases and total number of cases for the past 14 days per 100,000 residents) and the effective reproductive number were obtained daily from the King County Public Health COVID-19 dashboard. The primary outcome measure for this study was a new case of COVID-19 in a player or coach confirmed by diagnostic testing.
Results
Seattle United Surveillance
Seattle United has a total of 1906 players registered, with teams practicing 1 to 3 times per week for approximately 40 to 60 minutes each practice. Between June 29, 2020, and August 9, 2020, there were a total of 15,494 players that attended practice. Only 2 players tested positive for COVID-19 during the study period, both acquiring the infection from outside of Seattle United soccer activities. One player who tested positive developed symptoms of COVID-19 hours after an evening practice. Four players from that practice pod were briefly quarantined and all tested negative. Six additional players that had engaged in soccer activity with the infected player outside of Seattle United practice were also briefly quarantined and all tested negative. The second player who tested positive had been quarantined before symptoms arose and did not attend a Seattle United practice while potentially infectious.
In addition, 43 family members were tested for SARS-CoV-2 because of exposure outside of soccer. Two family members tested positive and, in both cases, the player within that family tested negative and underwent the appropriate quarantine before returning to practice. A total of 38 family members tested negative after a potential exposure; results were unknown in 3 individuals.
King County Versus Seattle United Prevalence
The average number of new cases per day throughout King County was 146.3 (range 59-220) during the study period. The average total number of cases over the past 14 days per 100,000 residents in King County was 81.8 (range 32-99). Converting the Seattle United data to a similar metric, the estimated number of new cases over 14 days per 100,000 players was 35.0 (Figure 1). The average effective reproductive number in King County was 1.4 (range 1.0-1.7) during the study period.
Total number of cases over the past 14 days per 100,000 population: King County versus Seattle United players.
Conclusion
Small group youth soccer training, when appropriately physically distanced, is safe and does not promote or accelerate spread of COVID-19 because of sports activities. In this study, all new cases identified in players or family members came from the community, with no case of player to player or coach to player spread during the 42-day study period. Multimedia education and close engagement of families, coaches, and club staff combined to create a soccer community with high awareness and compliance with safety protocols and physical distancing throughout the entire practice session. Contact tracing and additional guidance for families with illness or potential exposure to COVID-19 was an unanticipated benefit of our surveillance program. When comparing the prevalence of COVID-19 in King County to the equivalent prevalence within Seattle United, the number of new cases was 57% lower in Seattle United players than the general community. While this study is limited by its small sample size and the relatively low prevalence of COVID-19 in King County, it provides important data to inform public health recommendations for outdoor sports and recreation. Additional study is recommended when youth sports advances to full practice and competition involving physical contact. Understanding best practices for safe participation in athletics during the COVID-19 pandemic is essential to ensure a safe return to sports.
Footnotes
Acknowledgements
We are grateful to the Seattle United players, families, and coaching staff for their support and cooperation in this study.
The authors report no potential conflicts of interest in the development and publication of this artile.