The infected express

Back in the 90's there was a young college student who was very intelligent he goes by the name of Austin. Him and his partner eventually get married and start a like together! His partner's name goes by Victoria. They will have a intersex child in the near future and the child's name is Felix.
Felix will end up all alone in an orphanage where the staff will treat them horribly because of their gender identity. Although they will meet loads of other children with the same issues or problems.
Later on in the story a mysterious virus will appear that will infect most of the human population.
Felix and their friends have to find a way to save the world from becoming permanently infected by the deadly virus. They will have to use a very old train to travel around the world while on the mission to save numerous lives. Will they be able to survive this apocalypse?