- Scientists have found where Ebola lurks -- almost exclusively in fruit bats. As man has traveled and settled further and further up the Ebola river region he has come in contact with the life cycle of the Ebola virus in these bats. The bats have antibodies to the disease and are mostly resistant to it. They nest in trees and when they defecate in them the virus is transmitted onto to surface of the fruit which is eaten by monkeys. These monkeys contract the disease and die rapidly from it. If they bite another monkey they can transmit the disease to others in their troop, but they can also bite humans. The people of the area also eat monkey meat, so that's another vector for the disease.
- While Marburg, Lassa and Ebola are all very deadly diseases the strain that burned through Zaire in the book was particularly lethal for two reasons:
- The main story centers around a strain called "Ebola Zaire Mayinga" -- named after a nurse that contracted it trying to save someone else's life. For whatever reasons this is an insanely fast strain (90% lethal). It also almost killed the first doctor trying to treat it. He survived after going through many blood transfusions. USAMRIID has samples of Mayinga in cold storage.
- Mayinga's original method of infection was from Belgian nuns who had setup a center for malaria injections. They kept re-using the same needles and it's likely that one of the original people infected thought they had malaria and got an injection from the nuns. After that the ebola virus was being actively spread by the nuns to every single person getting an injection. More people who just came there to avoid malaria came down with Ebola. They spread the infection to their relatives who went to the mission for a malaria shot. The extreme amplification of the virus at the mission devastated the region. Within a week or so the entire mission (including the nuns) was totally destroyed.
- As you said, the Reston virus really had the potential to destroy the world. It broke out in experimental monkeys in a lab Reston VA imported from a region near the Phillipines IIRC. Unlike other Ebola strains it was transmitted not only by bodily fluids, but through the labs ventilation system (airborne). The only thing that saved humanity was blind luck that the variant probably had a single mutation that prevented it from infecting humans. Imagine a significant percentage of the DC area coming down with a 50-90% lethal flu and various diplomats catching it and flying it to their populations throughout the world. Given enough time Reston could have jumped over to humans, but quick action by USAMRIID, CDC and other military personnel stopped it there.
- More importantly regarding the posted article, there has been an experimental vaccine for Ebola for about the last 8-10 years. It saved the life of a lab worker in 2009 as has been shown to be effective in lab tests.