WHAT’S THE DIFFERENCE . . .

. . . between a virus and a retrovirus?

VIRUSES are microscopic organisms that can enter and infect another organism. They are, in essence, parasites: they cannot survive for long outside a host. Most ordinary viruses, including SARS-CoV-2, enter the host’s cells and use them to replicate, destroying the cell in the process and causing damage and disease.

Retroviruses, such as the HIV virus, do not destroy the host’s cells but inject their genetic material into them. This combines with the genetic material already inside, turning the cell into a mini-factory pumping out new copies of the retrovirus. Retroviruses can quickly mutate, with new viral variants existing within a single host. This makes it very difficult to find effective treatments.