I guess it really depends on what the case is, there are some medications that can stop these sorts of illnesses,but not all of the,. I think modern medication has come a long way,but who knows what causes one thing or another. maybe some medications might actually cause the deafness.
It is preventable in children now, thanks to modern medicine. The technology is there, at least. The problem here is that it is not nearly widespread enough to get to every child who is potentially born deaf. This is genetic tinkering and, though it is possible, it is not likely in most cases. Hopefully one day.
Even with advances in medical and modern Science, not all deaf children fit the criteria required to apply medical advances or technology to his or her own hearing problem.Although, in is is my belief deafness in children can be less prevalent now as well as in the future compared to the past,some children will have an unpreventable sickness or deformation that cause deafness.
No, I do not think that deafness in children is preventable thanks to modern medical science, because medicine does not allow us to go into the womb to identify and solve defects like deafness before the child is even born. It is also not something that is prevented by taking a vitamin.