Terminus

Centuries ago, the aquatic alien Sa arrived to explore Earth's wonders. Initially, they disregarded the dominant land-dwelling humans, viewing them as dangerous and primitive. However, the Sa explorers became marooned on Earth when an aggressive interstellar species invaded and occupied their home worlds. 
Now, human-induced climate change and nuclear weapon proliferation threaten the Sa's existence. With their expertise in genetic manipulation, the Sa created a hybrid human species called the HumanSo to alter man's destructive behavior toward Earth's ecology. Unfortunately, their efforts fail.
Believing they have no choice but to ensure their survival as a species, the Sa responds to the ongoing environmental disaster with a Sa-engineered human viral plague known as Terminus. While this drastic and genocidal solution may save Earth, the impact on both human and Sa cultures remains unclear. 
Trey Ocean, caught up in the ensuing maelstrom, must fight to protect his family as civilization collapses due to Terminus. The Ocean family is unique, possessing a hidden connection to the Sa rooted in Trey's tragic past. 
"Terminus" delves into the depths of human darkness and the heights of our capacity to love. 650 pages