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. HIV-1 is the most common type. When you hear the term "HIV," it's probably HIV-1. HIV-2 occurs in a much smaller number of people, mostly in West Africa. In the U.S., it makes up only 0.01% of all HIV cases, and those are primarily people from West Africa. It's harder to transmit HIV-2 from person to person, and it takes longer for the infection to turn into AIDS.
There are two main types of the human immunodeficiency virus (HIV), HIV-1 and HIV-2. The difference between HIV-1 and HIV-2 are as follows
- 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.
Currently, only one antibody test can distinguish between antibodies to HIV-1 or HIV-2.
It’s possible to contract more than one HIV strains. This is called superinfection. When superinfection occurs, the new strain can either replace or coexist in the body along with the original strain.
The exact prevalence of HIV superinfection is unknown, and estimates can vary based on individual studies. Some data suggest that the incidence rate of superinfection can range between 0 and 7.7 percent per year.
Infections With Multiple Strains
When the virus multiplies, the copies sometimes change (mutate) and develop into another HIV strain(s) in your body. You can end up with a HIV strains drugs won't work against. This makes your viral load -- the amount of HIV in your body -- go up. In that case, you'd need another type of treatment.
You also can have two or more strains if you were infected by more than one person. This is called superinfection. Superinfection is rare -- it happens in less than 4% of people. You're at the highest risk of superinfection in the first 3 years after you get HIV.
Everyone reacts differently to infection. You might not notice any change in your symptoms or viral load with a new infection. But it can make your HIV worse, especially if you have a strain drugs won't work well against. If that happens, the drugs you take for your original HIV strain won't necessarily treat the new strain.
