The human virome in health and disease

The Human Virome is vast, with many people familiar with persistent and latent infections. More than 50% of all adults are commonly positive for herpes viruses, CMV, EBV, HSV1, HHV6, HHV7, Polyomavirus, and Anelloviruses. Pathogenic viruses like HIV are also common in the human population, with roughly 0.8% of people testing positive. Some viruses, like SARS-CoV-2 and cold viruses, are transient and very common. Vaccinia virus vaccine strain is sometimes deliberately used to prevent smallpox infection.

The human genome contains about 8% recognizable fragments of endogenous retroviruses that infected the germ line in the primate lineage leading to humans. Long terminal repeat (LTR) sequences are common in human DNA, comprising 8% of the genome. Additionally, the human microbiome contains numerous viruses, bacteria, phage of bacteria, and archaea in human stool samples. When virus-like particles are purified and stained under a microscope, around 10 to the ninth virus-like particles per gram of human stool can be observed.