Sometimes it is simple filth that breeds disease. The hoax mongers spread fear causing depopulation by press conference. It is the best of Yacubian mythology: a black and black must not mate, only black and brown, then brown and yellow, then yellow and white, thus creating the white devil through genetic engineering. If a black and black mate and the woman gets pregnant, the nurse must kill the baby and inform the mother there was a birth defect and it was necessary to kill the baby, or maybe tell the mother the baby will be born with a small head so she must abort. This is the classic Yacubian mythology, utilizing three workers: doctor, nurse and undertaker.
Again, often it is simply filthy water or pesticide rather than a virus. For sure, water is the leading culprit. Nothing can come from filthy water except disease. But Dr. Yacub is also busy in his bio tech lab engineering mosquitoes carrying the virus, then another strain to neutralize the virus carrying agent. But clean the water, Stupid, mosquitoes breed in filthy water.
It is a scam, again, in the classic Yacubian method of population control by spreading fear and misinformation. Don't believe the hype!
The Nation of Islam theology claims that Yakub is the biblical Jacob. Mainstream Sunni and Shia Muslims do not have this belief, or anything similar to it. The story has caused disputes within the NOI during its history. Under its current leader Louis Farrakhan, the NOI continues to assert that the story of Yakub is true, stating that modern science is consistent with it.