Unvaccinated athlete denied entry to Australia: will they be banned from entering Australia again if they appeal against visa cancellation?

I'm asking since we have a group of athletes (surfing) from Europe (EU) to prepare in Australia for the 2022 season and have one athlete in a similar situation.

That athlete should insure that they fulfill the medical exception listed at the Australian Immunisation Register (AIR) site at the time the visa application is made and again before traveling in case the rules suddenly change.

Does this mean that if somebody's appeal against visa cancellation is dismissed, they could be banned from entering Australia for a certain time? If so, for how long?

That would depend on the individual situation.

If the person fulfilled the AIR conditions at the time the visa was applied for and again before departure, but due to a last minute change in the rules, no longer fulfilled them upon entry/arrival

• then a long term ban is unlikely

That would be most likely be considered a force majeure situation since the traveler showed good faith by fulfilling the AIR conditions at the time of the visa application and departure.

Preparing to travel to Australia from overseas | COVID-19 and the border

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Obtain your foreign vaccination certificate
If you are unable to meet the proof of vaccination requirements, you will not qualify as a fully vaccinated traveller. You will need to follow the current border processes when leaving or coming to Australia.

If you are coming to Australia, are unable to be vaccinated for medical reasons, and have a medical contraindication recorded in the Australian Immunisation Register (AIR) you can show an Australian COVID-19 digital certificate to airline staff. You can otherwise provide your immunisation history statement.

If you do not have your medical contraindication recorded in the AIR you will need to show airline staff a medical certificate. This must state you are unable to be vaccinated with a COVID-19 vaccine due to a medical condition.
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Immunisation medical exemptions - Australian Immunisation Register [AIR] - Services Australia

• Page last updated: 10 December 2021

What counts as a medical exemption
The only reasons you might be able to get an exemption from having a vaccine are if you:

• had anaphylaxis after a previous dose of a vaccine
• had anaphylaxis after a dose of any component of a vaccine
• are significantly immunocompromised—for live vaccines only
• have natural immunity—for hepatitis B, measles, mumps, rubella and chickenpox only.

What doesn’t count as a medical exemption
You won't be able to get an exemption if your reason for not having a vaccine isn't valid.

These aren’t valid reasons:

• mild illness without fever—meaning your temperature is below 38.5ºC
• any family history of adverse events following immunisation
• history of convulsions
• treatment with antibiotics
• treatment with locally acting steroids, inhaled or low dose topical
• replacement corticosteroids
• asthma, eczema, atopy, hay fever or sniffles
• previous infection with the same pathogen
• prematurity, vaccination shouldn’t be postponed and can be given if the infant is medically stable
• history of neonatal jaundice
• low weight in an otherwise healthy child
• neurological conditions, including cerebral palsy and Down syndrome
• contact with an infectious disease
• child’s mother is pregnant
• child is being breastfed
• woman is breastfeeding
• recent or planned surgery