Host Range and Specificity of Viruses
They are capable of infecting all forms of life (hosts)
The host range of a virus refers to the spectrum of hosts that a virus can infect.
Polioviruses, for example, can be grown in the laboratory in monkey kidney cells but have never been observed to cause a natural infection in any animals other than humans.
The rabies virus can attach the central nervous system of many warm-blooded animals.
Viral specificity refers to the specific kinds of cells a virus can infect.