Unemployment is an endemic problem in South Africa,...

https://www.merriam-webster.com/dictionary/endemic

1b : characteristic of or prevalent in a particular field, area, or environment ·problems endemic to translation ·the self-indulgence endemic in the film industry

I think this would be a good word choice as it evokes the idea of a more localized problem rather than the term epidemic which has connotations of a more widespread problem.

Additionally, borrowing from it's more common use in reference to disease helps mark it as something that requires an active treatment and will not correct itself on its own.

Unemployment is an endemic problem in South Africa,...

Merriam-Webster

1b : characteristic of or prevalent in a particular field, area, or environment ·problems endemic to translation ·the self-indulgence endemic in the film industry

I think this would be a good word choice as it evokes the idea of a more localized problem rather than the term epidemic which has connotations of a more widespread problem. You are focusing on South Africa in particular rather than on unemployment in general so use a word that focuses it.

Additionally, borrowing from it's more common use in reference to disease helps mark it as something that requires an active treatment and will not correct itself on its own.

You could also combine it with systemic for a more powerful sentence.

Endemic unemployement is a systemic problem in South Africa

Merriam-Webster:

systemic: of, relating to, or common to a system