You can be open and honest or you can forget it ever happened and let it slip your mind.
Personally, I'd be tempted to just go on the medical you have now and your present physical condition.
Alternatively, telephone the Aeromedical Centre and ask them - just don't give them your proper name.
If you do tell them they may very well take it into consideration. Remember there are hundreds applying for one job!!
This may sound somewhat deceitful but your circumstances exactly happened to a friend of mine, who was halfway through his heli training and was binned for having had childhood asthma at 3 years old, never having any form of pulmonary infection since. Super fit and binned for some mis-diagnosis from his childhood!! He'd forgotten all about it but they trawled his medical history and found it.
There is always the chance they will find out in any case, if the docs decide to go through your medical history with a fine tooth comb so you need to weigh up the pros and cons and make your decision.
HTH (but it probably doesn't)
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