Hi - Apologies in advance that this may not be the best place for post this, but I have a 90 minute connection in ADD which should be doable. However, if I miss the connection, I will likely have to spend more than 12 hours in the airport until the next flight.

1) Will this cause a visa/immigration issue since transit passengers are limited to 12 hours of visa-free transit?
2) My destination (South Africa) requires yellow fever vaccinations if you're in a country where that disease is prevalent (such as Ethiopia). What is the likelihood that an extended transit in Ethiopia would cause a problem in SA?

Thanks.