Difficult question to answer.
There are 2 types of hearing loss.
1) Acute and sudden....bomb blast
2) Noise exposure, less intense over a long period of time.
Surprisingly the inner ear is well protected and quite resilient.
It sounds as though the Vuvuzelas are " blasting off" at about 80dbs, that is just a guess from listening to the TV. Inner ear damage would depend upon how near you were and for how long.
In my opinion a person exposed to that noise fro 90 mins would be unlikely to develop noise induced hearing loss (NIHL), however for 2 or 3 matches he may well develop a high tone loss which would not be realised for about 20yrs. So the problem would not be now, but later in life. For that person attending many matches being exposed to 80 db continually, only ear protectors would save damage to his inner ear. This damage is quite discreet affecting the range of 2-4Khertz..... indistinguishable impairment until later in life.