Here in Nosy Be Island we are in the most developped place in Madagascar. There is no plague so far (only in the capitol Antananarivo) and no Malaria Outbreak here.
In this Island there is 3 different Hospitals with one employing most of the Occidental Technology and also few little Clinics.
About diving, we do have here a recompression chamber, but anyway, with your journey here you will be on a professional diving insurance.
The NGO have a Oxygen Kit everytime in good shape and full of oxygen. Same as medical first emergency kit.
For any other question please feel free to contact us we gonna answer ASAP.