Neurological disorder

A neurological disorder is a disorder of the body's nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord, or in the nerves leading to or from them, can result in symptoms such as paralysis, muscle weakness, poor coordination, loss of sensation, seizures, confusion, painand altered levels of consciousness. There are manyrecognized neurological disorders, some relatively common, but many rare. They may be revealed by neurological examination and studied and treated within the specialities ofneurology and clinical neuropsychology. Interventions include preventative measures, lifestyle changes, physiotherapy or other therapy, neurorehabilitation, pain management, medication, or operations performed byneurosurgeons. The World Health Organization estimated in 2006 that neurological disorders and theirsequelae affect as many as one billion people worldwide, and identified health inequalities and social stigma/discrimination as major factors contributing to the associated disability and suffering.

laboratory tests are used to monitor HIV

Two blood tests are routinely used to monitor HIV-infected people. One of these tests, which counts the number of CD4 cells, assesses the status of the immune system. The other test, which determines the so-called viral load, directly measures the amount of virus in the blood.
In individuals not infected with HIV, the CD4 count in the blood is normally above 400 cells per mm³ of blood. People generally do not become at risk for HIV-specific complications until their CD4 cells are fewer than 200 cells per mm³. At this level of CD4 cells, the immune system does not function adequately and is considered severely suppressed. A declining number of CD4 cells means that HIV disease is advancing. Thus, a low CD4 cell count signals that the person is at risk for one of the many opportunistic infections that occur in individuals who are immunosuppressed. In addition, the actual CD4 cell count indicates which specific therapies should be initiated to prevent those infections.

future for preventing HIV transmission

Early advances in preventing HIV transmission resulted from educational programs describing how transmission occurs and providing barrier protection for those exposed to genital secretions and new needles or bleach to those exposed to blood by sharing needles. Despite these efforts, new infection in both the developed and developing worlds has continued at high rates.
Historically, the greatest success in preventing viral transmission has resulted from the development of preventative vaccines. Unfortunately, decades of research to develop an HIV vaccine has led to little hope for success. In 2007, a major setback in this area occurred when the STEP study investigating a promising vaccine candidate was prematurely stopped due to the lack of evidence that it produced any protection from HIV infection. In contrast, a glimmer of hope did emerge with the report in 2009 of the results of the RV 144 Thai HIV vaccine trial which demonstrated borderline effectiveness in the more than 16,000 recipients. While this vaccine demonstrated only limited evidence of protection, research is under way to further explore what can be learned for future vaccine development from this modest success.

symptoms and signs of HIV

The time from HIV infection to the development of AIDS varies. Rarely, some individuals develop complications of HIV that define AIDS within one year, while others remain completely asymptomatic after as many as 20 years from the time of infection. However, in the absence of antiretroviral therapy the time for progression from initial infection to AIDS is approximately eight to10 years. The reason why people experience clinical progression of HIV at different rates remains an area of active research.
Within weeks of infection, many people will develop the varied symptoms of primary or acute infection which typically have been described as a "mononucleosis" or "influenza" like illness but can range from minimal fever, aches, and pains to very severe symptoms. The most common symptoms of primary HIV infection are

• fever,
• aching muscles and joints,
• sore throat,
• and swollen glands

key principles in managing HIV infection

First of all, there is no evidence that people infected with HIV can be cured by the currently available therapies. In fact, individuals who are treated for years and are repeatedly found to have no virus in their blood experience a prompt rebound in the number of viral particles when therapy is discontinued. Consequently, the decision to start therapy must balance the risk versus the benefits of treatment. The risks of therapy include the short- and long-term side effects of the drugs, described in subsequent sections, as well as the possibility that the virus will become resistant to the therapy which can limit options for future treatment.

How is HIV spread

HIV is present to variable degrees in the blood and genital secretions of virtually all individuals infected with HIV, regardless of whether or not they have symptoms. The spread of HIV can occur when these secretions come in contact with tissues such as those lining the vagina, anal area, mouth, eyes (the mucus membranes), or with a break in the skin, such as from a cut or puncture by a needle. The most common ways in which HIV is spreading throughout the world include sexual contact, sharing needles, and by transmission from infected mothers to their newborns during pregnancy, labor (the delivery process), or breastfeeding. (See the section below on treatment during pregnancy for a discussion on reducing the risk of transmission to the newborn.).
Sexual transmission of HIV has been described from men to men, men to women, women to men, and women to women through vaginal, anal, and oral sex. The best way to avoid sexual transmission is abstinence from sex until it is certain that both partners in a monogamous relationship are not HIV-infected. Because the HIV antibody test can take months to turn positive after infection occurs, both partners would need to test negative for at least 12 and up to 24 weeks after their last potential exposure to HIV. If abstinence is out of the question, the next best method is the use of latex barriers. This involves placing a condom on the penis as soon as an erection is achieved in order to avoid exposure to pre-ejaculatory and ejaculatory fluids that contain infectious HIV. For oral sex, condoms should be used for fellatio (oral contact with the penis) and latex barriers (dental dams) for cunnilingus (oral contact with the vaginal area). A dental dam is any piece of latex that prevents vaginal secretions from coming in direct contact with the mouth. Although such dams occasionally can be purchased, they are most often created by cutting a square piece of latex from a condom.

diagnosis of HIV

n 1985, a blood test became available that measures antibodies to HIV that are the body's immune response to the HIV. The test used most commonly for diagnosing infection with HIV is referred to as an ELISA. If the ELISA finds HIV antibodies, the results must be confirmed, typically by a test called a Western blot. HIV antibody tests remain the best method for diagnosing HIV infection. Recently, tests have become available to look for these same antibodies in saliva, some providing results within one to 20 minutes of testing. Antibodies to HIV typically develop within several weeks of infection. During this interval, patients have virus in their body but will test negative by the standard antibody test, the so called "window period." In this setting, the diagnosis can be made if a test is used that actually detects the presence of virus in the blood rather than the antibodies, such as tests for HIV RNA or p24 antigen. Recently, a new test has been approved that measures both HIV antibodies and p24 antigen, shrinking the duration of the window period from infection to diagnosis. There also are many testing centers around the country that are routinely screening blood samples that are HIV-antibody negative for HIV RNA. Although the tests for detecting HIV infection continue to improve, they still require that people volunteer for testing. It is estimated that approximately 20% of those infected with HIV in the United States are unaware of their infection because they have never been tested. In order to decrease the number that are unaware of their HIV infection status, in 2006, the Centers for Disease Control and Prevention recommended that all people between the ages of 13 and 64 years be provided HIV testing whenever they encounter the health-care system for any reason. In addition, resources are available to facilitate people finding local HIV testing centers