Those viruses are sexually transmitted.
All those viruses were originally bird flus.
Those viruses can be transmitted through saliva and other bodily fluids.
Church and his colleagues discovered that those viruses share a common genetic sequence.
"We have no idea how easily those viruses adapt to humans.
And those viruses helped make us who we are today just as surely as other genes did.
If those viruses don't take root, then the infection can't get going and amplify".
The book does not pretend to be a history of those viruses, or a technical manual on infectious diseases generally.
Vaccines are most successful when directed against those viruses that do not mutate and that infect only humans.
Virus-specific models were restricted only to species from taxonomical orders with confirmed hosts for those viruses (Supplementary Table 4).
Of those viruses that cause disease, some cause short-term (acute) diseases and others recurring or long-term (chronic) diseases.
