The term "viral agent" refers to any infectious microorganism that reproduces inside the cells of living organisms and is capable of causing disease in its host. Full definition
Although both these diseases can cause acute illness and death, canine and feline distemper should not be confused, as they are caused by two distinctly different viral agents. (lowchensaustralia.com)
Potential donors to tissue banks in the USA were found to have a 3.16 % prevalence of positive screening for the same viral agents, with 1.48 % confirmed positive. (skepticalob.com)
Tumor virology has survived its failure to find abundant viral agents of human cancer. (scientificamerican.com)