Question: How many people must be present for an event to be considered a mass gathering?

Answer passage (source: WHO):
page_title: Q&A: Mass gatherings and COVID-19
section_headers: How large does a meeting or event need to be in order to be a “mass gathering”?
section_content: High profile international sporting events such as the Olympics or World Cups
as well as international religious events such as the Hajj count as mass
gatherings. However, lower profile conferences and events can also meet WHO’s
definition of a mass gathering. An event counts as a “mass gatherings” if the
number of people it brings together is so large that it has the potential to
strain the planning and response resources of the health system in the
community where it takes place. You need to consider the location and duration
of the event as well as the number of participants. For example, if the event
takes place over several days in a small island state where the capacity of
the health system is quite limited then even an event with just a few thousand
participants could place a big strain on the health system and then be
considered a “mass gathering” event. Conversely, if the event is held in a big
city in a country with a large, well-resourced health system and lasts just a
few hours, the event may not constitute a “mass gathering” event.

Reviewer feedback on this answer:
While this answer relates to the question, it does not give a numerical number of how many people need to be present, although it gives examples.
While this technically answers the question, most people that would be searching for an answer are looking for something concrete (ie. A mass gathering is 3000 people or more)

Reviewer ratings:
Acceptable
Acceptable

Answer passage (source: WHO):
page_title: Q&A: Mass gatherings and COVID-19
section_headers: Does WHO recommend that all international mass gatherings be cancelled because of COVID-19?
section_content: No. As each international mass gathering is different, the factors to consider
when determining if the event should be cancelled may also differ. Any
decision to change a planned international gathering should be based on a
careful assessment of the risks and how they can be managed, and the level of
event planning. The assessment should involve all stakeholders in the event,
and in particular the health authorities in the country or community where the
event is due to take place. These authorities and stakeholders are in the best
position to assess the level of stress the event might place on the local
health system and emergency services – and whether this level of stress is
acceptable in the current situation.  
It is WHO’s view that all countries with community transmission should
seriously consider postponing or reducing mass gatherings that bring people
together and have the potential to amplify disease and support the recommended
best practice of physical distancing. Any decision will be supported through
the use of WHO tools, in particular the Risk Assessment for Mass Gatherings
during COVID-19.  
If movement restrictions and further national measures have been established
in the country, the WHO RA does not apply. However, when the process of re-
opening/conducting mass gatherings is being considered post movement
restrictions, it will be key to ensure any decisions are based on a risk
assessment, such as the WHO Mass gatherings COVID-19 risk assessment.

Reviewer feedback on this answer:
Needs to get rid of the No in the first part, it is not a yes/no question. Also doesn't answer the question.
This answer relates to whether an event should be cancelled, which is not what the original question asks.

Reviewer ratings:
Could be Improved
Bad

Answer passage (source: WHO):
page_title: Q&A: Mass gatherings and COVID-19
section_headers: If we go ahead with an international mass gathering, what can we do to reduce the risk of participants catching COVID-19?
section_content: Promote hand washing, respiratory hygiene and social distancing at the event.
Make sure you have emergency contact details for all participants, including
where they are staying during the event. You should make it clear to them that
this information will be shared with the local public health authorities to
enable rapid contact tracing if a participant at the event becomes ill with
COVID-19. The event organisers need to have an agreed preparedness plan in
case one or more participants become ill with COVID-19 symptoms. This should
include rapid isolation of the ill person and their safe transfer to a local
health facility. You should consider whether the number of participants at the
event could be reduced, making available participation by video or
teleconference and possibly screening participants for COVID-19 symptoms
(cough, fever, malaise) at points of entry to the venue. You can find advice
on how individual participants can protect themselves and their loved ones
from COVID-19 at: https://www.who.int/emergencies/diseases/novel-
coronavirus-2019/advice-for-public

Reviewer feedback on this answer:
Question is about the size of mass gatherings but the answer is about events in general and keeping attendees safe.
This answer only relates to what one should do at an event to protect themselves. The question, however, asks how many people must be present for an event to be a mass gathering, so this is unrelated.

Reviewer ratings:
Bad
Bad