SARS-CoV-2 transmission among supporters attending soccer mass gathering events

The majority of professional sport matches were cancelled or played without
supporters during the SARS-CoV-2 pandemic. The highest echelon of professional
soccer in the Netherlands (*the Eredivisie*) will resume in September 2020.
Supporters will be allowed to attend these matches under specific restrictions
regarding physical distancing and triage, but in popular clubs this may amount
to high numbers of individuals. A recent study concluded soccer matches to be
safe for the players, as the number of high-risk contact moments during matches
is limited (1). However, possible transmission of SARS-CoV-2 among supporters
attending soccer matches has not yet been studied.

Our objective is to study SARS-CoV-2 transmission of a- and pre-symptomatic
carriers during a mass gathering event with social distancing and hygiene
public health measures.

Secundary objectives:
- To estimate the prevalence of a- and pre-symptomatic SARS-CoV-2 infections
among visitors of a mass gathering event.
- To assess environmental contamination with SARS-CoV-2.
- To asses compliance to public health advices among soccer supporters who
attended the match.

This study is a longitudinal observational cross-sectional cohort study.
Supporters of soccer club Feyenoord will be followed for six consecutive home
matches starting November 2020 (depending on when supporters are permitted to
enter the stadium). Supporters include season cardholders attending the match
and employees working at stadium *de Kuip* during the match. Due to COVID-19,
only a supporters owning a season card will be allowed to attend the home
matches.

All season card holders of soccer club Rotterdam (Feyenoord) and employees
working in the stadion will be asked to participate in this study by email.
Oro- and nasopharyngeal swabs will be obtained before each match. The swabs,
used for the detection of SARS-CoV-2, will be obtained from a yet to be
determined randomly selected amount supporters attending the match.
Environmental specimens (surface swabs and sewage waste water) will be
collected both during (sewage) and after the match. SARS-CoV-2 transmission
will be identified using enhanced surveillance via the diagnostic test facility
of the local public health service (*GGD teststraat*). Positive specimens will
be sequenced by whole-genome sequencing for transmission chain analysis. An
overview of study events is shown in Appendix A (in Dutch).


1. Environmental specimen
efore and after each home match surface swabs and sewage waste water will be
collected. Surface sampling for the detection of SARS-CoV-2 will be performed
according to the WHO surface sampling guidelines (7).

2. Oro- and nasopharyngeal swab
Before each soccer match a random sample of supports will be asked to get
tested for SARS CoV 2. A naso- and oropharyngeal swab a will be collected and
tested by RT-PCR. Data of the tested supporters will be collected. The GGD will
be informed if supporters were positive for SARS-CoV-2. Our research team will
inform supporters who are positive for SARS-CoV-2 and ask specific questions in
order to decide if the supporter was a- or pre- symptomatic at the time of the
test. These supporters will be followed up by the GGD for routine contact
tracing. Samples might also be tested for other respiratory viruses or other
pathogens.

3.Surveillance by GDD contact tracing
The GGD will implement specific questions on Feyenoord soccer match attendance
or contact with someone who attended a soccer match to the questionnaire used
for routine contact tracing. Consequently, if the patients has attended the
match, specific questions on entrance location and seat number at the stadium
will be asked.

4. Whole genome sequencing of SARS-CoV-2
All positive specimens will be sequenced using whole-genome sequencing (WGS) at
the Erasmus MC (EMC) Viroscience laboratory to identify transmission clusters.
Specimens obtained from supporters before attending the match will be tested by
RT-PCR and positive specimens will be sequenced at the department of
Viroscience at Erasmus MC. Positive specimens from supporters identified via
the GGD diagnostic facilities will be requested from the respective
laboratories within the GGD Rotterdam Rijnmond region and sent to Erasmus MC
for WGS.

Undergoing a naso- and oropharyngeal swab is unconfortable. However,
participation is voluntary and provides valuable information for the supporter
himself. There are no risks associated with the collection of a naso and
oropharyngeal swab.