Worldwide an estimated 33 million people are living with HIV, including more than 1 million in the United States. As a foundation for understanding the global impact of HIV/AIDS, it is helpful to consider the biology and transmission of the disease, as well as how it can affect life on both individual and community levels.

HIV, or the human immunodeficiency virus, is the virus that can lead to AIDS, or acquired immune deficiency syndrome. Once a person is HIV-positive, or infected with HIV, he or she is permanently infected. HIV infects certain types of white blood cells, known as T-cells, which help fight diseases. Inside the human body, the virus attaches to T-cells and multiplies, destroying the cells and weakening the immune system. Eventually, the person's immune system can no longer effectively fight off diseases.

HIV infection becomes AIDS when a person has such a high viral load, or high amount of HIV in their bodies, and such a low T-cell count, that the immune system becomes too weak to fight off infections it would otherwise be able to. Being unable to recover from opportunistic infections, like pneumonia or tuberculosis, is usually the cause of death for people with AIDS.

At this time, there is no vaccine for preventing HIV infection and no cure for AIDS. Medications known as antiretroviral (ARV) drugs can however, slow the destruction of an HIV-positive person's immune system. Today, antiretroviral therapy can give people living with HIV a near normal lifespan if they stay otherwise healthy. Still, most people who are infected with HIV, especially those living in low and middle income countries, do not have reliable access to antiretroviral medications or necessary health care services.

The Centers for Disease Control and Prevention (CDC) highlight three main ways that HIV is transmitted from person to person: having unprotected sex with someone who is HIV positive, sharing needles or equipment for injecting drugs with someone who is HIV positive, or being born to an infected mother.

The HIV virus cannot reproduce outside the human body. This means that HIV is not spread through air, water, insects, saliva, tears, sweat, shaking hands, sharing dishes, or kissing.

Recently, the CDC reported that the number of people living with HIV in the United States is higher than ever before. Every nine and a half minutes, someone in the U.S. becomes newly infected with HIV. While HIV and AIDS occur in all parts of the country, urban areas, including Baltimore, Miami, New Orleans, New York, San Francisco, and Washington, D.C. currently experience the most cases. To reduce the spread of HIV, initiatives in the U.S. have focused on preventing sexual transmission of HIV; discouraging the use of injectable drugs and needle sharing; and encouraging people at risk for HIV infection to have their blood, urine, or saliva tested for the presence of HIV antibodies, which the immune system produces when a person is HIV positive. Testing is the only way to know for sure whether you are HIV-positive. In the U.S., one in seven people living with HIV is unaware of their infection.

While HIV and AIDS are worldwide problems, infection rates vary across regions and countries. The highest HIV prevalence occurs in Sub-Saharan Africa, where nearly 68% of the world's HIV positive population lives. In parts of this region, as many as 1 in 4 adults are infected with HIV. Outside Sub-Saharan Africa, there are also high infection rates in parts of the Caribbean, Eastern Europe, and Central Asia. Nearly 30 million people living with HIV live in low- or middle-income countries; only about 5.25 million people in this group have access to antiretroviral therapies. International humanitarian organizations have worked with drug manufacturers to make affordable HIV medications available in developing countries.

Having a high rate of HIV and AIDS can present serious social and economic challenges for communities in developing countries. People debilitated by HIV and AIDS may be unable to do their daily work, including growing food to meet their nutritional needs or earning income to support their families. Having parents with HIV can not only put children at risk for being born HIV positive, it can also increase their chances of being orphaned. An estimated 16 million children under 18 have been orphaned by AIDS. These children may become the primary caregivers for younger brothers and sisters, a responsibility that can prevent them from going to school as they work to meet their family's basic needs. In countries with already limited infrastructure, working to care for increasing numbers of HIV/AIDS patients may also put a strain on local health care resources. When low-income communities suffer from these types of social and economic setbacks, it can present them with significant challenges for rising out of poverty.

The Peace Corps is a partner in the President's Emergency Plan for AIDS Relief (PEPFAR), an initiative to provide assistance to countries most affected by HIV and AIDS. Many Peace Corps Volunteers across the globe are trained as advocates and educators of HIV/AIDS prevention and care. Volunteers serve in public health education and collaborate with community and nongovernmental organizations in their host countries to address concerns related to HIV and AIDS.

Sources

• Avert
• Centers for Disease Control and Prevention (CDC)
• U.S Statistics, HIV.gov
• The United States President's Emergency Plan for AIDS Relief (PEPFAR)

Vocabulary

AIDS: Acquired Immune Deficiency Syndrome; an advanced stage of HIV infection in which the immune system cannot fight off infections

Antiretroviral drugs: Medications that suppress viruses such as HIV

HIV: Human Immunodeficiency Virus; the virus that causes AIDS

HIV antibodies: Proteins produced in an HIV-positive person?s body to help control HIV infection

Immune system: The cells, proteins, tissues, and organs that prevent disease in the human body

Infection rate: Number of new infections within a population over a defined period of time

Needle sharing: Using a syringe that someone else has already used to inject intravenous drugs

Opportunistic infection: An infection by a pathogen that would not typically make a healthy person sick

Prevalence: Proportion of individuals within a population affected by a disease at a given time

T-cells: A type of white blood cell that fights off diseases

T-cell count: A measure of the number of T-cells in a person's blood; this can provide information about the health of the person's immune system

Transmitted: Transferred from one person to another

Viral load: Amount of a given virus within a person's body

Virus: A microscopic infectious organism that multiplies inside the cells of its host