Human immunodeficiency virus infection / Acquired immunodeficiency syndrome (HIV/AIDS) is a disease of the human immune system caused by the human immunodeficiency virus (HIV). The illness interferes with the immune system, making people with AIDS much more likely to get infections. This susceptibility increases as the disease worsens.
In 1981, a new syndrome, the acquired immune deficiency syndrome (AIDS), was first recognized among homosexual men in the United States. By 1983, the etiological agent, the human immunodeficiency virus (HIV), had been identified. By the mid-1980’s, it became clear that the virus had spread, largely unnoticed, throughout most of the world.
The number of people living with HIV rose from around 8 million in 1990 to 34 million by the end of 2010. The overall growth of the epidemic has stabilised in recent years. The annual number of new HIV infections has steadily declined and due to the significant increase in people receiving antiretroviral therapy, the number of AIDS-related deaths has also declined. Since the beginning of the epidemic, nearly 30 million people have died from AIDS-related causes.
There is no way to know for sure if someone else has HIV unless they have an HIV test. Many people with HIV look perfectly healthy. Other people who are sick with HIV may have symptoms that are identical to other common illnesses.
Human immunodeficiency virus (HIV) is the causative agent for AIDS. The most common type is known as HIV-1 and is the infectious agent that has led to the worldwide AIDS epidemic. There is also an HIV-2 that is much less common and less virulent, but eventually produces clinical findings similar to HIV-1. The HIV-1 type itself has a number of subtypes (A through H and O) which have differing geographic distributions but all produce AIDS similarly.
The organ involvement of infections with AIDS represents the typical appearance of opportunistic infections in the immunocompromised host--that of an overwhelming infection--that makes treatment more difficult. The strategies employed in AIDS patients to meet this challenge consist of (1) preserving immune function as long as possible with antiretroviral therapies, (2) using prophylactic pharmacologic therapies to prevent infections (such as Pneumocystis jiroveci pneumonia), and (3) diagnosing and treating acute infections as soon as possible.
HIV treatment does not cure HIV, and people with HIV still may experience complications related to HIV treatment and HIV infection. However, the current outlook for people with HIV has improved tremendously and HIV-infected people with access to medicines and medical care can live long, healthy lives. A person diagnosed at age 25 who receives good medical care is estimated to live 40 more years.
A vaccine is the world's best hope for ending the AIDS pandemic. Vaccines are one of the most effective public health interventions. ... AIDS vaccine development is challenging, but possible. The scientific evidence is mounting.
Jon Cohen, a correspondent for Science who has written extensively about the virus, compares the work to fossil hunting, using a few precious shreds of evidence to construct a possible history. ...At least a few of [the facts] are undisputed -- including, most significantly, HIV's family tree. There are two species of the virus, HIV-1 and HIV-2. The first evolved from a simian immunodeficiency virus (SIV) found in chimpanzees, while the second came from an SIV in a type of monkey called the sooty mangabey.
Despite the increase in the number of people living with HIV infection, the annual number of new infections (HIV incidence) has remained relatively stable. Recent data suggests that HIV prevention efforts are taking hold, namely (1) Lower transmission rate. The majority of people infected with HIV do not transmit the virus to others. and (2) More know of their HIV infection. The estimated proportion of persons in the United States with HIV who know they are infected increased from 75% in 2003 to 79% in 2006.
The most reliable ways to avoid becoming infected with or transmitting HIV are:
- Abstain from sexual intercourse (i.e., oral, vaginal, or anal sex)
- Be in a long-term, mutually monogamous relationship with an uninfected partner
- Abstain from sharing needles and/or syringes for nonprescription drugs