What are the evolutionary origins of HIV-1 and HIV-2?

What are the evolutionary origins of HIV-1 and HIV-2?

From Africa, HIV rapidly spread in the late 1960s to the Caribbean and then the United States, Europe, and other areas of the world, leading to the global AIDS pandemic. Both HIV-1 and HIV-2 descended genetically from Simian immunodeficiency virus via cross-species transmission.

What is the main difference between HIV-1 and HIV-2?

HIV-1 is the most common type of HIV and accounts for 95% of all infections, whereas HIV-2 is relatively uncommon and less infectious. HIV-2 is mainly concentrated in West Africa and the surrounding countries. HIV-2 is less fatal and progresses more slowly than HIV-1.

What family does HIV belong to?

Retroviruses are a family of viruses that are grouped together based on how they are structured and how they replicate within a host. Besides human immunodeficiency virus (HIV), the virus that causes AIDS, there a two other retroviruses that can cause human illness.

Can a person have HIV-1 and HIV-2?

Abstract. HIV-1 and HIV-2 are two related retroviruses and, in regions where both infections are endemic, HIV-1/2 dual infection can occur.

Can humans get SIV?

The risk of human infection with SIV is no longer merely hypothetical. We have documented such an infection and have isolated SIV from a person who became infected after exposure to SIV-infected nonhuman primates.

What do retroviruses contain?

Most retroviruses are spherical particles, approximately 100 nm in diameter, consisting of an internal protein core surrounded by an envelope of glycoproteins embedded in a lipid bilayer. The core contains several copies of reverse transcriptase bound to two identical single-stranded RNA molecules.

How many HIVS are there?

There are two main types of human immunodeficiency virus (HIV) — HIV-1 and HIV-2. Both can lead to AIDS. However, they’re very different from each other.