Yes! East Africa is relatively a safe place. It’s true there have been a few political-related riots in Uganda and Kenya in the past couple of months however these don’t affect a traveler’s’ movements because the riots are normally contained in a particular part of the city.
Also, almost all East African safaris are in the rural parts of the countries so unless you’re doing a city tour, your safari will not be interrupted.
DRC has however had long periods of insecurities and recently an Ebola outbreak; though comparatively these insecurities and Ebola have been contained your safety in DRC is not a 100% guarantee.
When on a safari, it’s imperative for you to take all necessary precautions as instructed by the guides and tour operators, so that you avoid unpleasant run-ins with the wild animals, which run-ins can be become fatal.