There is no need to get vaccins for Bonaire.
There are several doctors and a complete hospital with a decompression chamber and there is an AED (Automated External Defibrillator) on the premises.
Salt water from the sea is processed into drinking water. It is of very good quality. Drink enough water, at least 1,5 liter per day to avoid dehydration!
Take precautions against the sun, especially between 11 am and 3 pm. Use sun blocks, sun glasses, a hat. And remember that the chances of getting sun burned increase on the water while surfing or snorkling.