Ricean Vampires have a beginning. They begin about 6000 years ago, in Egypt. A Pharaoh and his Queen, were contaminated by a demon when this demon entered their bodies through bleeding wounds. From this point the infection was only passed through ingestion of the blood of an infected person, a Vampire. Now because of the immense time that is involved there are only a few Vampires that have seen that day. 3 to be exact. Maharet, Mekare, and Khyman. Of these only Maharet has been "awake" the whole time. The problem with Immortality is that a lot of vampires have a hard time dealing with 'forever'. To us mortals it means nothing, to them it is the only absolute left. So in order to deal with this 2 "safety nets" take place. One is to "go into the ground" this is when the vampire buries himself or herself and basically hibernates. Blood is not required and the Vampire can will themselves out of this at their own choice. The other way they come with millennia is that they go into a trance, and they become living statues. And of course there is always suicide. But I wouldn't call that a safety net.
Now, Ricean Vampires have a certain "connection" with one another through a Queen Vampire, the current Queen is Mekare. If any thing were to happen to Mekare it would effect the entire Vampire population. For instance, if She were to be burned then all Vampires would burn. If she were to die without her crown being passed through a ritual, all Vampires would die. In 6000 years the crown has only been passed once and that was just over a decade ago. So that Crown won't be passed for some time now.