HIV - Human Immunodeficiency Virus

It has been more than twenty years since the Human Immunodeficiency Virus (HIV) epidemic was first discovered. However, even though a long period of time has passed, no cure has been found for this deadly virus and HIV still remains an enigma for scientists and researchers.   It is one of the deadliest viruses discovered up till now and causes Acquired Immune deficiency Syndrome (AIDS).

Cases of HIV infection are now reported throughout the world. Earlier, specific at-risk populations were identified, but as the epidemic grew, this risk pool expanded to include new populations. New discoveries and latest therapies appear to be quite promising but they have not proved as the complete cure for this deadly virus.

History of HIV

HIV causes one of the deadliest diseases known as AIDS. This Acquired Immune deficiency Syndrome (AIDS) epidemic began with the appearance of a cluster of cases of Pneumocystis carinii pneumonia in young people who were homosexuals in 1981. In the ensuing months, reports of other rare disorders affecting previously healthy individuals in major urban centers of the United States were published.

Since homosexuals, bisexuals, intravenous drug users (IVDU) and hemophiliacs were initially reported as groups at risk for AIDS. Early epidemiologic studies suggested an apparent blood-borne or sexual route of transmission even before the causative agent was discovered.

AIDS was initially found in males as the HIV was found most commonly among gay population. This contributed to the public perception of AIDS as a gay disease. However, even early in the HIV epidemic, IVDU and people receiving contaminated blood products were found to have relatively high incidences of HIV infection. Homosexuals, bisexuals, IVDU, recipients of contaminated blood products, their sexual partners and their children constituted the populations at high risk for HIV infection throughout the first decade of the HIV epidemic in the United States.

Modes of Transmission

Sexual Transmission

Sexual contact is a common method of HIV transmission in the United States and world over. Most of the HIV transmission has been reported due to the sexual contact among gays.

While the overall incidence of new HIV infections in homosexuals has dropped, certain subgroups continue to have high sero-conversion rates. Hispanic and black homosexuals continue to have disproportionately high infection rates. However, HIV is found among alarming number of women and children too.

Intravenous Drug Users

The second chief mode of transmission of HIV infection in the United States is intravenous drug users i.e. by using the same needle or syringe that was previously used by an HIV infected person. The sharing of needles and syringes is a very effective method of HIV transmission. IVDU's represent a group; susceptible to a very rapid spread of HIV once it is introduced within the group.

In the U.S. and Europe this has lead to secondary infections within general population.

Blood Transfusion

Blood transfusion is considered as the most efficient means of HIV transmission with infection rates estimated to be approximately 90%. In 1985, HIV antibody screening of all donated blood along with discouraging people at risk for HIV from donating blood led to a dramatic decrease in HIV transmission by blood.

However, it remains risky since antibodies to HIV are often not detectable during the first several months after infection. The decrease in HIV transmission via blood transfusions has been one of the notable successes in the battle against HIV disease in the United States.

In many parts of the world however, this almost completely preventable route of infection is still very common. The basic concepts of safe donors, proper testing of blood and the appropriate use of blood must be emphasized to implement improvement in blood product safety.

Perinatal Transmission

A large number of children of age group 0-4 years are found suffering from AIDS. This is direct reflection of increase in HIV-infected women and perinatal transmission of HIV to infants. Whether transmission of HIV occurs prenatally, at parturition or via breast feeding is not yet clear.

The incidence of HIV infection in children is expected to rise in the United States as the number of HIV-infected women increases. In many areas of the world, this phenomenon is expected to reverse infant mortality advances.

HIV still remains the deadliest infection causing deadliest of diseases, AIDS. There are various ways by which this disease spreads. However, caution in safe sex, blood transfusion and use of fresh needles and syringes can prevent this disease from spreading further and save thousands of lives.