Just a comment: the photo in this thread appears to be of a swarm of bees that has temporarily settled on a limb while looking for a new home.
When swarming, honeybees, including Africanized bees, generally are not aggressive. There are rare exceptions that prove the rule, but in general swarms are in the natural process of establishing a new colony and do not have a hive and brood to protect. Thus, they are not particularly aggressive. They are MUCH more aggressive when their established hives or nests are disturbed.
When honeybees swarm (usually in the spring) the old queen has been superseded by a new queen, and the new queen and part, maybe 50 to 60%, of the original colony moves to a new location, which is the way honeybees of all kinds expand and reproduce. This is a good thing, except for beekeepers who lose a strong colony and have to let it rebuild.
I'm a beekeeper but have little direct experience with Africanized bees, although I have talked with a number of beekeepers in Belize and elsewhere who have successfully adapted to keeping Africanized bees. Africanized honeybees have some advantages, such as being more resistant to mites and viruses that plague regular beekeepers, but they are more aggressive in defending their nests/hives than European and other bees. Their sting isn't any worse than that of regular honeybees, but they do tend to attack what the hive "brain" considers a threat, and they keep attacking for a long time.