Retroviruses belong to the Retroviridae family of viruses. Their genetic material consists of ribonucleic acid (RNA), rather than deoxyribonucleic acid (DNA). Viruses of this type also contain reverse transcriptase. Retroviruses are known to cause certain types of cancer in both humans and animals, as well as a variety of viral infections. Human Immunodeficiency Virus (HIV), the virus that causes Acquired Immune Deficiency Syndrome (AIDS), is one example.
These viruses are unique in that they reproduce by transcribing themselves into DNA. Reverse transcriptase, an enzyme within a retrovirus, makes it possible for RNA to function as a kind of template for the transcription process. Once transcription has taken place, the viral DNA gains access to a cell's DNA, reproducing along with the cell and its offspring. Within the cell's offspring, called daughter cells, the viral DNA creates RNA replicas of itself. Finally, these replicas leave the daughter cells after being coated with a protein.
Retroviruses reverse the normal cellular process, which uses RNA to synthesize DNA. By reversing this process, they take up permanent residence in the genetic material of the infected cell. In some cases, these viruses destroy the cells that change; Such is the case with HIV. Others cause cells to become cancerous. This is what happens with certain types of leukemia.
Viruses in this family are prone to mutation and for this reason often become resistant to antiviral drugs in a relatively short period of time. This level of mutability is one of the reasons cited for the difficulty scientists face in trying to develop a safe and effective vaccine against HIV.
Antibiotics are not effective against retroviruses. They are useful for fighting bacterial infections, but are useless against viruses. Instead, antiviral drugs must be developed and used to combat them. Vaccination can be used to prevent diseases caused by viruses, including retroviruses. Unfortunately, developing effective vaccines is a complicated job that can take years, or even generations, to accomplish.
Although retroviruses are indicated in some life-threatening diseases, they are vulnerable to something as simple as ordinary soap and water. Hand washing can render them inactive. Physical barriers can also be helpful in preventing its spread. Such barriers include condoms, rubber gloves, and face masks.