Origins of HIV

Researchers found that chimpanzees carried a strain of the HIV-1 virus in West Africa. It is theorized that hunters made contact with infected chimpanzees and were contaminated by blood as they cut it for meat. From here the virus was spread via normal human channels, such as sex, travel, drugs, unsanitary medical practices, and war (Know Curriculum, 2007 Revision).

Chimpanzees carried a strain of the HIV-1 virus.

A separate HIV-2 virus was identified from this group, and is largely known to be isolated in western Africa, but conclusions about HIV-1 origins are still missing. New discoveries are being made as time goes on. For instance, a small number of northern Europeans have been found to have genetic resistance to HIV infection, interestingly with no differences found in risk groups (J Urban, Resistance to HIV Infection, 2006).

A gene mutation linked to northern Europeans helps prevent HIV by inhibiting its abilities to detect CD4 and CCR5 co-receptors, the two conditions necessary for HIV to attach itself to a white blood cell.

Why HIV is Widespread

HIV is an equal opportunity infection. Anyone can contract it, just as they can transmit it. Nearly a quarter in fact do not know they have it (Know Curriculum, 2007 Revision). The only thing that can be done about HIV transmission is to influence how society lowers the infection rate. Here is a common list of reasons why countries with weak infrastructure have higher rates of infection in comparison to countries with better infrastructure.

Underfunded Country Factors


Developed Country Factors


HIV Related Statistics from the CDC


Prevalence is the number of people living with HIV infection at a given time, such as at the end of a given year. At the end of 2015, an estimated HIV prevalence of 1.1 million persons aged 13 and older were living with HIV infection in the United States, including an estimated 162,500 (15%) persons whose infections had not been diagnosed (Dailey et al., 2017).

Incidence is the number of new HIV infections that occur during a given time period. In 2014, the estimated number of new HIV infections in the United States was 37,600. Estimated annual HIV infections in the United States declined 10% from 2010 to 2014 (Singh et al., 2017).

In 2016, the number of new HIV diagnoses in the United States was 39,782. There were 32,131 diagnoses among adult and adolescent males (13 years or older), 7,529 among adult and adolescent females, and 122 among children younger than 13 years.

In 2016, the number of new HIV diagnoses in the United States was 39,782. There were 32,131 diagnoses among adult and adolescent males (13 years or older), 7,529 among adult and adolescent females, and 122 among children younger than 13 years.

At the end of 2015, there were 973,846 persons living with diagnosed HIV infection in the United States.

The number of persons in the United States whose diagnosed HIV infection was classified as stage 3 (AIDS) in 2016 was 18,160. Of these, 13,851 stage 3 (AIDS) classifications were among adult and adolescent males, 4,271 were among adult and adolescent females, and 38 were among children younger than 13.

In 2015, the number of deaths of persons with diagnosed HIV infection ever classified as stage 3 (AIDS) in the United States was 12,497.  The cumulative number of deaths of persons with diagnosed HIV infection ever classified as stage 3 (AIDS) in the United States, through 2015, was 692,789.

Note: Because of delays in reporting of deaths, data are only available through the end of 2015. The exclusion of data from the most recent year allows at least 18 months for deaths of persons with an AIDS diagnosis to be reported.



HIV Risk Groups

These following groups are at the highest risk for HIV:



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