Hiv History upto 1983

Up to 1980

We do not know how many people developed AIDS in the 1970s, or indeed in the years before.

"The dominant feature of this first period was silence, for the human immunodeficiency virus (HIV) was unknown and transmission was not accompanied by signs or symptoms salient enough to be noticed. While rare, sporadic case reports of AIDS and sero-archaeological studies have documented human infections with HIV prior to 1970, available data suggest that the current pandemic started in the mid- to late 1970s. By 1980, HIV had spread to at least five continents (North America, South America, Europe, Africa and Australia). During this period of silence, spread was unchecked by awareness or any preventive action and approximately 100,000-300,000 persons may have been infected."Jonathan Mann¹

We also do not know for certain where the AIDS virus HIV originated, but it is now generally accepted that the origin of AIDS can be traced back to Africa.

1981 History

Kaposi's Sarcoma (KS) was a rare form of relatively benign cancer that tended to occur in older people. But by March 1981 at least eight cases of a more aggressive form of KS had occurred amongst young gay men in New York.

At about the same time there was an increase, in both California and New York, in the number of cases of a rare lung infection Pneumocystis carinii pneumonia (PCP).³ In April this increase in PCP was noticed at the Centers for Disease Control (CDC) in Atlanta. A drug technician, Sandra Ford, observed a high number of requests for the drug pentamine, used in the treatment of PCP:

"A doctor was treating a gay man in his 20s who had pneumonia. Two weeks later, he called to ask for a refill of a rare drug that I handled. This was unusual - nobody ever asked for a refill. Patients usually were cured in one 10-day treatment or they died"Sandra Ford for Newsweek

In June, the CDC published a report about the occurrence, without identifiable cause, of PCP in five men in Los Angeles.⁵ This report is sometimes referred to as the "beginning" of AIDS, but it might be more accurate to describe it as the beginning of the general awareness of AIDS in the USA.

A few days later, following these reports of PCP and other rare life-threatening opportunistic infections, the CDC formed a Task Force on Kaposi's Sarcoma and Opportunistic Infections (KSOI).

Dr. Conant and Dr Volverg discussing Kaposi's Sarcoma. Circa 1981

Around this time a number of theories emerged about the possible cause of these opportunistic infections and cancers. Early theories included infection with cytomegalovirus, the use of amyl nitrite or butyl nitrate 'poppers', and 'immune overload'.

Because there was so little known about the transmission of what seemed to be a new disease, there was concern about contagion, and whether the disease could by passed on by people who had no apparent signs or symptoms.¹⁰ Knowledge about the disease was changing so quickly that certain assumptions made at this time were shown to be unfounded just a few months later. For example, in July 1981 Dr Curran of the CDC was reported as follows:

"Dr. Curran said there was no apparent danger to non homosexuals from contagion. 'The best evidence against contagion', he said, 'is that no cases have been reported to date outside the homosexual community or in women'"The New York Times

Just five months later, in December 1981, it was clear that the disease affected other population groups, when the first cases of PCP were reported in injecting drug users. At the same time the first case of AIDS was documented in the UK.

1982 History

As the disease still did not have a name, organisations were referring to it in different ways. The CDC generally referred to it by reference to the diseases that were occurring, for example lymphadenopathy (swollen glands), although on some occasions they referred to it as KSOI, the name already given to the CDC task force.

In contrast some still linked the disease to its initial occurrence in gay men, with a letter in The Lancet calling it "gay compromise syndrome". Others called it GRID (gay-related immune deficiency), AID (acquired immunodeficiency disease), "gay cancer" or "community-acquired immune dysfunction".

In June a report of a group of cases amongst gay men in Southern California suggested that the disease might be caused by an infectious agent that was sexually transmitted.

By the beginning of July a total of 452 cases, from 23 states, had been reported to the CDC.

Later that month the first reports appeared that the disease was occurring in Haitians, as well as haemophiliacs. This news soon led to speculation that the epidemic might have originated in Haiti, and caused some parents to withdraw their children from haemophiliac camps.

The occurrence of the disease in non-homosexuals meant that names such as GRID were redundant. The acronym AIDS was suggested at a meeting in Washington, D.C., in July. By August this name was being used in newspapers and scientific journals.    AIDS (Acquired Immune Deficiency Syndrome) was first properly defined by the CDC in September.

By the beginning of July a total of 452 cases, from 23 states, had been reported to the CDC.

An anagram of AIDS, SIDA, was created for use in French and Spanish. Doctors thought AIDS was an appropriate name because people acquired the condition rather than inherited it; because it resulted in a deficiency within the immune system; and because it was a syndrome, with a number of manifestations, rather than a single disease.

Still very little was known about transmission and public anxiety continued to grow.

"It is frightening because no one knows what's causing it, said a 28-year old law student who went to the St. Mark's Clinic in Greenwich Village last week complaining of swollen glands, thought to be one early symptom of the disease. Every week a new theory comes out about how you're going to spread it."The New York Times 

By 1982 a number of AIDS specific voluntary organisations had been set up in the USA. They included the San Francisco AIDS Foundation (SFAF), AIDS Project Los Angeles (APLA), and Gay Men's Health Crisis (GMHC).In November 1982 the first AIDS organisation, the Terry Higgins Trust (later known as the Terrence Higgins Trust), was formally established in the UK, and by this time a number of AIDS organisations were already producing safer sex advice for gay men.

In December a 20-month old child who had received multiple transfusions of blood and blood products died from infections related to AIDS.³⁴ This case provided clearer evidence that AIDS was caused by an infectious agent, and it also caused additional concerns about the safety of the blood supply. Also in December, the CDC reported the first cases of possible mother to child transmission of AIDS.

By the end of 1982 many more people were taking notice of this new disease, as it was clearer that a much wider group of people was going to be affected.

"When it began turning up in children and transfusion recipients, that was a turning point in terms of public perception. Up until then it was entirely a gay epidemic, and it was easy for the average person to say 'So what?' Now everyone could relate."Harold Jaffe of the CDC for newsweek 

It was also becoming clear that AIDS was not a disease that just occurred in the USA. Throughout 1982 there were separate reports of the disease occurring in a number of European countries.

Meanwhile in Uganda, doctors were seeing the first cases of a new, fatal wasting disease. This illness soon became known locally as 'slim'.

1983 History

In January, reports of AIDS among women with no other risk factors suggested the disease might be passed on through heterosexual.

At about the same time the CDC convened a meeting to consider how the transmission of AIDS could be prevented, and in particular to consider the newly emerged evidence that AIDS might be spread through blood clotting factor and through blood transfusions. As James Curran, the head of the CDC task force, said:

"The sense of urgency is greatest for haemophiliacs. The risk for others [who receive blood products] now appears small, but is unknown.”

The risk for haemophiliacs was so great because the blood concentrate that some haemophiliacs used exposed them to the blood of up to 5,000 individual blood donors.

In March, the CDC stated that,

"persons who may be considered at increased risk of AIDS include those with symptoms and signs suggestive of AIDS; sexual partners of AIDS patients; sexually active homosexual or bisexual men with multiple partners; Haitian entrants to the United States; present or past abusers of IV drugs; patients with haemophilia; and sexual partners of individuals at increased risk for AIDS."

The same report also said,

"each group contains many persons who probably have little risk of acquiring AIDS... Very little is known about risk factors for Haitians with AIDS."

Nevertheless, the inclusion of Haitians as a risk group caused much controversy. Haitian Americans complained of stigmatisation, officials accused the CDC of racism, and Haiti suffered a serious blow to its tourism industry. Before long people were talking colloquially of a "4-H Club" at risk of AIDS: homosexuals, haemophiliacs, heroin addicts and Haitians. Some people substituted 'hookers' for haemophiliacs.

In May 1983, doctors at the Institute Pasteur in France reported that they had isolated a new virus, which they suggested might be the cause of AIDS.

In the UK there were public concerns about the blood supply with references in newspapers to "killer blood". The media more generally started to take notice of AIDS, with the screening of a TV Horizon programme, "The Killer in the Village", and a number of newspaper articles on the subject of the "gay plague".

In May 1983, doctors at the Institute Pasteur in France reported that they had isolated a new virus, which they suggested might be the cause of AIDS. Little notice was taken of this announcement at the time, but a sample of the virus was sent to the CDC. A few months later the virus was named lymphadenopathy-associated virus or LAV, patents were applied for, and a sample of LAV was sent to the National Cancer Institute.

But whilst progress was being made by scientists there was increasing concern about transmission, and not just in relation to the blood supply. A report of AIDS occurring in children suggested quite incorrectly the possibility of casual household transmission.

AIDS transmission became a major issue in San Francisco, where the Police Department equipped patrol officers with special masks and gloves for use when dealing with what the police called "a suspected AIDS patient"
.

"The officers were concerned that they could bring the bug home and their whole family could get AIDS."The New York Times

And in New York:

"landlords have evicted individuals with AIDS" and "the Social Security Administration is interviewing patients by phone rather than face to face."Dr David Spencer, Commisioner of Health, New York City

There was considerable fear about AIDS in many other countries as well:

"In many parts of the world there is anxiety, bafflement, a sense that something has to be done - although no one knows what."The New York Times

As anxiety continued, the CDC tried to provide reassurance that children with AIDS had probably acquired it from their mothers and that casual transmission did not occur:

"The cause of AIDS is unknown, but it seems most likely to be caused by an agent transmitted by intimate sexual contact, through contaminated needles, or, less commonly, by percutaneous inoculation of infectious blood or blood products. No evidence suggests transmission of AIDS by airborne spread. The failure to identify cases among friends relatives, and co-workers of AIDS patients provides further evidence that casual contact offers little or no risk [...] the occurrence in young infants suggests transmission from an affected mother to a susceptible infant before, during, or shortly after birth."

Reports from Europe suggested that two rather separate AIDS epidemics were occurring. In the UK, West Germany and Denmark, the majority of people with AIDS were homosexual, and many had a history of sex with American nationals. However in France and Belgium AIDS was occurring mainly in people from Central Africa or those with links to the area.

Examples of this second epidemic included a number of previously healthy African patients who were hospitalised in Belgium with opportunistic infections (such as PCP and cryptosporidosis), Kaposi's sarcoma, or other AIDS-like illnesses. All of these Africans had immune deficiency similar to that of American AIDS patients. However they had no history of blood transfusion, homosexuality, or intravenous drug use. In light of such reports, European and American scientists set out to discover more about the occurrence of AIDS in Central Africa.

By this time, doctors working in parts of Zambia and Zaire had already noticed the emergence of a very aggressive form of Kaposi's sarcoma. This cancer was endemic in Central Africa, but previously it had progressed very slowly and responded well to treatment, whereas the new cases looked very different and were often fatal.

In September the CDC published their first set of recommended precautions for health-care workers and allied professionals designed to prevent "AIDS transmission". In the UK, people who might be particularly susceptible to AIDS were asked not to donate blood.

In October, the first European World Health Organisation (WHO) meeting was held in Denmark. At the meeting it was reported that there had been 2,803 AIDS cases in the USA.

That meeting was followed in November by the first meeting to assess the global AIDS situation. This was the start of global surveillance by the WHO and it was reported that AIDS was present in the U.S.A., Canada, fifteen European countries, Haiti and Zaire as well as in seven Latin American countries. There were also cases reported from Australia and two suspected cases in Japan.

By the end of the year the number of AIDS cases in the USA had risen to 3,064 and of these 1,292 had died.

How to Test and Treat Hiv And Aids

The "test and treat" method to treating HIV is relatively new, and it has mixed results. There are positives to the approach, but there are negatives as well. Broadly defined, the "test and treat" method is designed to diagnose HIV infection early and reduce the viral load so that the HIV-positive patients don't spread the virus to others. It is seen as a method capable to curb the epidemic as antiretroviral therapy, or ART, is frequently given far too late after the initial infection. This gives time for the infected person to pass the virus on to others.

Since up to a quarter of all HIV-infected individuals don't know it yet, they can be highly infectious to others-especially if they engage in risky activity. "Test and treat" aggressively tests people for HIV and then, if found to be HIV-positive, are then treated with antiretroviral drugs in an attempt to slow the spread of the virus to others. Early treatment can reduce the viral load to one ten-thousandth of what it would be without treatment. A person with this viral load would be one twenty-fifth as likely to infect another person with HIV. This can reduce the spread of the virus, but a strict lifelong adherence to the treatment regimen is necessary.

Some investigators argue that since 19% of all HIV-infected individuals in the US have an undetectable viral load, the "test and treat" method is not effective by itself to control the spread of HIV. Test-and-treat is undermined primarily by three things: Late diagnosis, a low level of referral and retention in HIV specialist care, and a lack of adherence to antiretroviral therapy programs. The investigators also concluded that over a third of HIV-treated people in the US would have a detectable viral load, and because of this would still be at risk for spreading HIV to other people.

The "test and treat" method has been lauded as a way to control the spread of the epidemic. HIV-positive patients who have an undetectable viral load while on antiretroviral therapy are at a much lower risk to spread the virus, as stated before. However, a fifth of all new infections remain undiagnosed. In the United States, there are approximately 1.1 million HIV-positive individuals, and about 56,000 people are diagnosed with HIV each year. If the "test and treat" method is effective on a significant enough percentage of the 56,000 new HIV-positive patients, it could go a long way toward reducing the number of new HIV-positive cases being discovered every year.

International Symposium on HIV & Emerging Infectious Diseases (ISHEID): the world leading AIDS experts will gather for the 2012 HIV AIDS ISHEID conference in Marseille, France, May 23-25, 2012. The general AIDS conference theme will be 'From Universal HIV Testing to HIV Cure'.

By Alain Lafeuillade

Hiv Test And Treatment

HIV infected individuals can undergo a large selection of laboratory tests, some of these tests may include viral load test and CD4 test. Though antiretroviral treatment can be administered to individuals diagnosed with HIV, it is almost impossible to predict the "right time" to begin treatment because diagnosis of this viral infection can be very difficult as it is very much similar to typical viral infections and can also be asymptomatic.

The viral load test or the antiretroviral [ARV] treatment is the only treatment available that has promising results to patients who has been infected by the HIV. Though reports and feedback from people who have undergone the treatment has testified the treatment's safety and improbability of causing complications, still there are things that are not to be taken for granted such as possible complications in the drug treatment like for instance; adverse effects, resistance, adherence, and interactions. The kind of application of the treatment is still debated on when it is best and most effectively applied, but the treatment on the advance stage of HIV is most believed by the majority to be most effective and efficient time to administer treatment.

There are only a handful tests available to diagnose an adult with HIV, among all, the most used and suitable test for adults would be the HIV Antibody test. ELISA (enzyme-linked immunoabsorbent) or EIA (enzyme immunoassay) is the most used antibody test because it is known for its precision and is inexpensive. The detection of the HIV can be made as early as 6-12 weeks. The antibodies of the infected person will fight of the infection, and thus by using the antibody test, it will now scan the saliva, urine, or blood for antibodies. If Hive antibodies are found in any of the three, you can now declare an HIV infection.

HIV testing is practically advised to be taken by people who engage in unprotected sex, people who shared injections of drugs, or seemingly suspect that they were administered with a used syringe, and to people who are or were exposed by HIV in their workplace. But the test is open to every individual who wishes to take it, as long as you suspect that you might be infected with HIV, you can take the test.

HIV testing can be done in your home by home testing kits by obtaining a blood sample of yourself and sending it to a laboratory for HIV testing. Though many would prefer the home kit for reasons of saving themselves from the humility of entering a STD clinic and preventing a scandalous emotional breakdown in public, you must remember that the precision of the blood sampling is at risk when you do it yourself, it is most advised to have the test in a STD clinic, where you can have a full scan and full test and the physician can have a full history and development of your condition.

HIV Testing - before anything turns out to be too late, take the lead and act now. Find out now and learn more about HIV testing.

By Ruben Head

Hiv Symptoms - When to Get Tested

There is a common misconception among many people these days that HIV home tests are unnecessary for them. While some people still believe that the disease only exists among prostitutes, homosexuals, and IV drug users, the HIV statistics prove that people of any age, race, sexual preference, or lifestyle can contract the disease. While sexual intercourse is by far the most common means of transmission, any contact with the blood or bodily fluids of an infected person can result in transmitting the illness. It is very important to understand that anyone who is sexually active or comes into contact with the bodily fluids of others is at risk of developing HIV.

Another common misconception among many is that HIV testing is only needed if you begin to show symptoms of being sick. While HIV does have numerous symptoms, it is important to know that many people do not show HIV symptoms at all for months or even years. While diseases such as herpes and gonorrhea have specific symptoms, HIV is an immune deficiency, which means that its main effect is that it makes people more susceptible to other illnesses. For this reason, people who are HIV positive often think that a cold or flu is often a symptom only of itself and miss being diagnosed altogether.

In most cases, the early development of HIV is entirely symptom free. People who do show HIV/ AIDS symptoms during this stage often mistake them for the flu, as a fever, muscle pain, and swollen lymph glands are the most common effects. Later symptoms of the disease can range from chronic diarrhea to sudden weight loss, sores on the mouth and skin, rashes, exhaustion, and sweating as well as chronic yeast infections. Because all of these symptoms can also be found with other illnesses, it is important to undergo regular HIV testing to ensure that your status is negative. When diagnosed early, many people can live remarkably long and healthy lives with HIV.

HIV becomes detectable anywhere from a few weeks to a few months after transmission. As the disease begins to spread within the body, the immune system will begin to develop antibodies. The presence of these antibodies is what allows a diagnosis to be made by doctors. While they often develop within a few weeks, it is important to be tested for at least a year after contact with someone who is positive and to get tested regularly if you are sexually active or are exposed to bodily fluids.

Testing for HIV can be done in many ways by doctors. For people seeking a confidential and private way to test for HIV antibodies, an HIV home test allows you to perform a simple needle stick and mail the sample to a lab for rapid analysis. You will never be asked to give personally identifiable information and will be able to learn your results from the privacy of your own home. The test is virtually painless, and results can be available anywhere from the next day to a few weeks. Knowing your HIV status is crucial, and home HIV test kits make it easier than ever to always have the answer.

There are many medical home test kits on the market today. If you or someone you know ever needs one, there are three things to consider... confidentiality, accuracy and a fair price. Make sure you go to a reputable online website that only uses Medical Home Testing Kits that are FDA approved (or cleared).

By Lila Abrams

Aids Diagnosis - Home Kit Method

Getting an HIV test can be stressful and embarrassing for many people. Due to the stigma that still surrounds the disease, many people fear that having HIV will cause people to judge them as promiscuous or to make assumptions about drug use. While the medical community is now well aware of HIV statistics and the ways that HIV can be transmitted, and of the fact that anyone who is sexually active or comes into contact with blood is at risk, this stigma keeps many people from getting tested. HIV home testing is an excellent way for people to find out for certain whether or not they are HIV positive, without having to face doctors and community members in a local clinic. These tests are anonymous and highly accurate.

A HIV home test is done using a finger stick much like those performed on diabetics to measure blood sugar levels. The sample is then sent to a lab, where results will be available anywhere from the day they are received to a few weeks later, depending on the test and the company. Most companies allow people to send in their HIV home test using only PIN numbers or codes that they set up so that results are completely confidential. Counseling is also offered in many cases, regardless of a positive or negative result in order to help people learn to prevent the disease and to ensure that people are prepared in case the result is positive.

The FDA does not allow HIV test results to be determined or read at home. There are many reasons for this, and it is due in large part to the amount of work required to determine that a diagnosis is accurate. Because HIV is considered such a serious diagnosis, it is a primary goal of these companies to ensure that accurate results are always given.

If your HIV home test shows a positive result, you will be instructed to see a local doctor to confirm the results. False positives are highly unlikely, but confirming the diagnosis is always recommended, as is seeking prompt treatment. HIV is no longer the near-immediate death sentence that it once was, but maintaining proper treatment is imperative.

If your HIV home test is negative, then you should simply maintain a regular testing schedule. While all people should be tested every six months, if you have been exposed to HIV infected blood or someone with HIV/AIDS symptoms, it is important to be tested every twelve weeks for a full year. It can take some time for HIV symptoms and antibodies to develop within the body after exposure.

In short, HIV home testing certainly works and is an excellent idea. While seeing your doctor can be the best method of testing for many and can help ensure that you are psychologically prepared for the results, HIV home testing offers fast results and confidential treatment. Your health is very important, and knowing your HIV status is crucial for anyone who is sexually active or who has a job with a risk of bleeding. If you do not know your HIV status, it is certainly advised that you use a HIV home testing kit to learn the truth right away.

There are many medical home test kits on the ma Permalink rket today. If you or someone you know ever needs one, there are three things to consider... confidentiality, accuracy and a fair price. Make sure you go to a reputable online website that only uses Medical Home Testing Kits that are FDA approved (or cleared).

By Lila Abrams

Hiv-Diagnosis

 

HIV tests are used to detect the presence of the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome (AIDS), in serum, saliva, or urine. Such tests may detect antibodies, antigens, or RNA.

  

The window period is the time from infection until a test can detect any change. The average window period with HIV-1 antibody tests is 25 days for subtype B. Antigen testing cuts the window period to approximately 16 days and NAT (Nucleic Acid Testing) further reduces this period to 12 days.

Performance of medical tests is often described in terms of:

• sensitivity: The percentage of the results that will be positive when HIV is present
• specificity: The percentage of the results that will be negative when HIV is not present.

All diagnostic tests have limitations, and sometimes their use may produce erroneous or questionable results.

• False positive: The test incorrectly indicates that HIV is present in a non-infected person.
• False negative: The test incorrectly indicates that HIV is absent in an infected person.

Nonspecific reactions, hypergammaglobulinemia, or the presence of antibodies directed to other infectious agents that may be antigenically similar to HIV can produce false positive results. Autoimmune diseases, such as systemic lupus erythematosus, have also rarely caused false positive results. Most false negative results are due to the window period.

Principles

Screening donor blood and cellular products

Tests selected to screen donor blood and tissue must provide a high degree of confidence that HIV will be detected if present (that is, a high sensitivity is required). A combination of antibody, antigen and nucleic acid tests are used by blood banks in Western countries. The World Health Organization estimated that, as of 2000, inadequate blood screening had resulted in 1 million new HIV infections worldwide.  

In the USA, since 1985, all blood donations are screened with an ELISA test for HIV-1 and HIV-2, as well as a nucleic acid test. These diagnostic tests are combined with careful donor selection. As of 2001, the risk of transfusion-acquired HIV in the U.S. was approximately one in 2.5 million for each transfusion.

Diagnosis of HIV infection

Tests used for the diagnosis of HIV infection in a particular person require a high degree of both sensitivity and specificity. In the United States, this is achieved using an algorithm combining two tests for HIV antibodies. If antibodies are detected by an initial test based on the ELISA method, then a second test using the Western blot procedure determines the size of the antigens in the test kit binding to the antibodies. The combination of these two methods is highly accurate (see below).

Human rights

The UNAIDS/WHO policy statement on HIV Testing states that conditions under which people undergo HIV testing must be anchored in a human rights approach that pays due respect to ethical principles. According to these principles, the conduct of HIV testing of individuals must be

• Confidential;
• Accompanied by counseling (for those who test positive);
• Conducted with the informed consent of the person being tested.

Confidentiality

Considerable controversy exists over the ethical obligations of health care providers to inform the sexual partners of individuals infected with HIV that they are at risk of contracting the virus. Some legal jurisdictions permit such disclosure, while others do not. More state funded testing sites are now using confidential forms of testing. This allows for monitoring of infected individuals easily, compared to anonymous testing that has a number attached to the positive test results. Controversy exists over privacy issues.

In developing countries, home-based HIV testing and counseling (HBHTC) is an emerging approach for addressing confidentiality issues. HBHTC allows individuals, couples, and families to learn their HIV status in the convenience and privacy of their home environment. Rapid HIV tests are most often used, so results are available for the client between 15 and 30 minutes. Furthermore, when an HIV positive result is communicated, the HTC provider can offer appropriate linkages for prevention, care, and treatment.

Anonymous testing

Testing that has only a number attached to the specimen that will be delivered for testing. Items that are confirmed positive will not have the HIV infected individual's name attached to the specimen. Sites that offer this service advertise this testing option.^[

Routine testing recommendation

In the United States, one emerging standard of care is to screen all patients for HIV in all health care settings.^[7] In 2006, the Centers for Disease Control announced an initiative for voluntary, routine testing of all Americans aged 13–64 during health care encounters. An estimated 25% of infected individuals were unaware of their status; If successful the effort was expected to reduce new infections by 30% per year.^[8] The CDC recommends elimination of requirements for written consent or extensive pre-test counseling as barriers to widespread routine testing.

Antibody tests

HIV antibody tests are specifically designed for routine diagnostic testing of adults; these tests are inexpensive and extremely accurate.

Window period

Antibody tests may give false negativef (no antibodies were detected despite the presence of HIV) results during the window period, an interval of three weeks to six months between the time of HIV infection and the production of measurable antibodies to HIV seroconversion. Most people develop detectable antibodies approximately 30 days after infection, although some seroconvert later. The vast majority of people (97%) have detectable antibodies by three months after HIV infection; a six-month window is extremely rare with modern antibody testing. During the window period, an infected person can transmit HIV to others although their HIV infection may not be detectable with an antibody test. Antiretroviral therapy during the window period can delay the formation of antibodies and extend the window period beyond 12 months.^[10] This was not the case with patients that underwent treatment with post-exposure prophylaxis . Those patients must take ELISA tests at various intervals after the usual 28 day course of treatment, sometimes extending outside of the conservative window period of 6 months. Antibody tests may also yield false negative results in patients with X-linked agammaglobulinemia; other diagnostic tests should be used in such patients.

Three instances of delayed HIV seroconversion  occurring in health-care workers have been reported;^[11] in these instances, the health-care workers tested negative for HIV antibodies greater than 6 months postexposure but were seropositive within 12 months after the exposure.  DNA sequencing confirmed the source of infection in one instance. Two of the delayed seroconversions were associated with simultaneous exposure to hepatitis C virus (HCV). In one case, co-infection was associated with a rapidly fatal HCV disease course; however, it is not known whether HCV directly influences the risk for or course of HIV infection or is a marker for other exposure-related factors.

ELISA

The enzyme-linked immunosorbent assay (ELISA), or enzyme immunoassay (EIA), was the first screening test commonly employed for HIV. It has a high sensitivity.

In an ELISA test, a person's serum is diluted 400-fold and applied to a plate to which HIV antigens have been attached. If antibodies to HIV are present in the serum, they may bind to these HIV antigens. The plate is then washed to remove all other components of the serum. A specially prepared "secondary antibody" — an antibody that binds to human antibodies — is then applied to the plate, followed by another wash. This secondary antibody is chemically linked in advance to an enzyme. Thus the plate will contain enzyme in proportion to the amount of secondary antibody bound to the plate. A substrate for the enzyme is applied, and catalysis by the enzyme leads to a change in color or fluorescence. ELISA results are reported as a number; the most controversial aspect of this test is determining the "cut-off" point between a positive and negative result.

Western blot

Western blot test results. The first two strips are a negative and a positive control, respectively. The others are actual tests.

Like the ELISA procedure, the western blot is an antibody detection test. However, unlike the ELISA method, the viral proteins are separated first and immobilized. In subsequent steps, the binding of serum antibodies to specific HIV proteins is visualized.

Specifically, cells that may be HIV-infected are opened and the proteins within are placed into a slab of gel, to which an electrical current is applied. Different proteins will move with different velocities in this field, depending on their size, while their electrical charge is leveled by a surfactant called sodium lauryl sulfate. Some commercially prepared Western blot test kits contain the HIV proteins already on a cellulose acetate strip. Once the proteins are well-separated, they are transferred to a membrane and the procedure continues similar to an ELISA: the person's diluted serum is applied to the membrane and antibodies in the serum may attach to some of the HIV proteins. Antibodies that do not attach are washed away, and enzyme-linked antibodies with the capability to attach to the person's antibodies determine to which HIV proteins the person has antibodies.

There are no universal criteria for interpreting the western blot test: The number of viral bands that must be present may vary. If no viral bands are detected, the result is negative. If at least one viral band for each of the GAG, POL, and ENV gene-product groups are present, the result is positive. The three-gene-product approach to western blot interpretation has not been adopted for public health or clinical practice. Tests in which less than the required number of viral bands are detected are reported as indeterminate: a person who has an indeterminate result should be retested, as later tests may be more conclusive. Almost all HIV-infected persons with indeterminate western blot results will develop a positive result when tested in one month; persistently indeterminate results over a period of six months suggests the results are not due to HIV infection. In a generally healthy low-risk population, indeterminate results on western blot occur on the order of 1 in 5,000 patients. :However for those individuals that have had high-risk exposures to individuals where HIV-2 is most prevalent, Western Africa, an inconclusive western blot test may prove infection with HIV-2. The HIV proteins used in western blotting can be produced by recombinant DNA in a technique called recombinant immunoblot assay (RIBA).

Rapid or point-of-care tests

A woman demonstrates the use of the OraQuick rapid HIV test

Rapid antibody tests are qualitative immunoassays intended for use as a point-of-care test to aid in the diagnosis of HIV infection. These tests should be used in conjunction with the clinical status, history, and risk factors of the person being tested. The positive predictive value of Rapid Antibody Tests in low-risk populations has not been evaluated. These tests should be used in appropriate multi-test algorithms designed for statistical validation of rapid HIV test results.

If no antibodies to HIV are detected, this does not mean the person has not been infected with HIV. It may take several months after HIV infection for the antibody response to reach detectable levels, during which time rapid testing for antibodies to HIV will not be indicative of true infection status. For most people, HIV antibodies reach a detectable level after two to six weeks.

Although these tests have high specificity, false positives do occur. Any positive test result should be confirmed by a lab using the western blot.

Home Access Express HIV-1 Test is the only FDA-approved home test: the patient collects a few blood drops from a fingerstick, and mails the sample to a laboratory; results and counseling are obtained over the phone. All results are anonymous and confirmed before they are released.

OraQuick is an antibody test that provides results in 20 minutes. The blood, plasma or oral fluid is mixed in a vial with developing solution, and the results are read from a sticklike testing device. Usually detects HIV 1 and HIV 2.

Orasure is an HIV test that uses mucosal transudate from the tissues of cheeks and gums. It is an antibody test that first employs ELISA, then western blot.

Uni-Gold is a rapid HIV antibody test that provides results in 10–12 minutes. A drop of blood is placed on the device with developing solution. Uni-Gold is only FDA approved to test for HIV 1.

Clearview Complete HIV 1/2 and Clearview HIV 1/2 Stat-Pak are rapid tests for the detection of HIV 1 and HIV 2 antibodies in blood, serum, or plasma samples. Results are provided within 15 minutes.

There is also a urine test; it employs both the ELISA and the western blot techniques.

iDiagnostics Rapid HIV Test is, according only to their website, a non-FDA-approved home test. The company sells a blood test and a urine test produced by InTec PRODUCTS, INC. Similar to a home pregnancy test the patient collects a drop of blood/urine and drops the sample onto a cassette. Results are read visually in 15 minutes.  The accuracy of this test has not been confirmed by the FDA, and it is not authorized for sale in the United States.

The INSTI HIV-1/HIV-2* Rapid Antibody Test is a rapid in vitro qualitative test for the detection of antibodies to Human Immunodeficiency Virus Type 1 in human whole blood, serum or plasma. The test is intended for use by trained personnel in medical facilities, clinical laboratories, emergency care situations, and physicians' offices as a screening assay capable of providing test results in less than 60 seconds. The assay is packaged as a kit containing INSTI Membrane Units, Sample Diluent, Color Developer and Clarifying Solution, and is available in point-of-care use packaging, or packaging suitable for laboratory use.

Reveal HIV is a rapid in vitro qualitative test for the detection of antibodies to HIV in whole blood, serum or plasma. Reveal is among the fastest rapid HIV test available and it detects signs of early infection better than some other rapid tests. Reveal HIV is approved in Canada, the United States, Europe, Africa, Asia, and South America.

Interpreting antibody tests

ELISA testing alone cannot be used to diagnose HIV, even if the test suggests a high probability that antibody to HIV-1 is present. In the United States, such ELISA results are not reported as "positive" unless confirmed by a Western Blot.

The ELISA antibody tests were developed to provide a high level of confidence that donated blood was NOT infected with HIV. It is therefore not possible to conclude that blood rejected for transfusion because of a positive ELISA antibody test is in fact infected with HIV. Sometimes, retesting the donor in several months will produce a negative ELISA antibody test. This is why a confirmatory Western Blot is always used before reporting a "positive" HIV test result.

Rare false positive results due to factors unrelated to HIV exposure are found more often with the ELISA test than with the Western Blot. False positives may be associated with medical conditions such as recent acute illnesses and allergies. A rash of false positive tests in the fall of 1991 was initially blamed on the influenza vaccines used during that flu season, but further investigation traced the cross-reactivity to several relatively non-specific test kits.A false positive result does not indicate a condition of significant risk to health. When the ELISA test is combined with Western Blot, the rate of false positives is extremely low, and diagnostic accuracy is very high (see below).

HIV antibody tests are highly sensitive, meaning they react preferentially with HIV antibodies, but not all positive or inconclusive HIV ELISA tests mean the person is infected by HIV. Risk history, and clinical judgement should be included in the assessment, and a confirmation test (Western blot) should be administered. An individual with an inconclusive test should be re-tested at a later date.

Accuracy of HIV testing

Modern HIV testing is highly accurate. The evidence regarding the risks and benefits of HIV screening was reviewed in July 2005 by the U.S. Preventive Services Task Force. The authors concluded that:

...the use of repeatedly reactive enzyme immunoassay followed by confirmatory Western blot or immunofluorescent assay remains the standard method for diagnosing HIV-1 infection. A large study of HIV testing in 752 U.S. laboratories reported a sensitivity of 99.7% and specificity of 98.5% for enzyme immunoassay, and studies in U.S. blood donors reported specificities of 99.8% and greater than 99.99%. With confirmatory Western blot, the chance of a false-positive identification in a low-prevalence setting is about 1 in 250 000 (95% CI, 1 in 173 000 to 1 in 379 000).

The specificity rate given here for the inexpensive enzyme immunoassay screening tests indicates that, in 1,000 HIV test results of healthy individuals, about 15 of these results will be a false positive. Confirming the test result (i.e., by repeating the test, if this option is available) could reduce the ultimate likelihood of a false positive to about 1 result in 250,000 tests given. The sensitivity rating, likewise, indicates that, in 1,000 test results of HIV infected people, 3 will actually be a false negative result (the McGovern-Tirgari anomaly). However, based upon the HIV prevalence rates at most testing centers within the United States, the negative predictive value of these tests is extremely high, meaning that a negative test result will be correct more than 9,997 times in 10,000 (99.97% of the time). The very high negative predictive value of these tests is why the CDC recommends that a negative test result be considered conclusive evidence that an individual does not have HIV.

Of course, the actual numbers vary depending on the testing population. This is because interpreting of the results of any medical test (assuming no test is 100% accurate) depends upon the initial degree of belief, or the prior probability that an individual has, or does not have a disease. Generally the prior probability is estimated using the prevalence of a disease within a population or at a given testing location. The positive predictive value and negative predictive value of all tests, including HIV tests, take into account the prior probability of having a disease along with the accuracy of the testing method to determine a new degree of belief that an individual has or does not have a disease (also known as the posterior probability). The chance that a positive test accurately indicates an HIV infection increases as the prevalence or rate of HIV infection increases in the population. Conversely, the negative predictive value will decrease as the HIV prevalence rises. Thus a positive test in a high-risk population, such as people who frequently engage in unprotected anal intercourse with unknown partners, is more likely to correctly represent HIV infection than a positive test in a very low-risk population, such as unpaid blood donors.

Many studies have confirmed the accuracy of current methods of HIV testing in the United States, reporting false-positive rates of 0.0004 to 0.0007 and false-negative rates of 0.003 in the general population.

Antigen tests

The p24 antigen test detects the presence of the p24 protein of HIV (also known as CA), the capsid protein of the virus. Monoclonal antibodies specific to the p24 protein are mixed with the person's blood. Any p24 protein in the person's blood will stick to the monoclonal antibody and an enzyme-linked antibody to the monoclonal antibodies to p24 causes a color change if p24 was present in the sample.

This test is no longer used routinely in the US  or the EU  to screen blood donations since the objective was to reduce the risk of false negatives in the window period. Nucleic acid testing (NAT) is more effective for this purpose, and p24 antigen testing is no longer indicated if a NAT test is performed. The p24 antigen test is not useful for general diagnostics, as it has very low sensitivity and only works during a certain time period after infection before the body produces antibodies to the p24 protein.

Nucleic acid-based tests (NAT)

Nucleic-acid-based tests amplify and detect one or more of several target sequences located in specific HIV genes, such as HIV-I GAG, HIV-II GAG, HIV-env, or the HIV-pol. Since these tests are relatively expensive, the blood is screened by first pooling some 8-24 samples and testing these together; if the pool tests positive, each sample is retested individually. Although this results in a dramatic decrease in cost, the dilution of the virus in the pooled samples decreases the effective sensitivity of the test, lengthening the window period by 4 days (assuming a 20-fold dilution, ~20hr virus doubling time, detection limit 50 copies/ml, making limit of detection 1,000 copies/ml). Since 2001, donated blood in the United States has been screened with nucleic-acid-based tests, shortening the window period between infection and detectability of disease to a median of 17 days (95% CI, 13-28 Days, assumes pooling of samples). A different version of this test is intended for use in conjunction with clinical presentation and other laboratory markers of disease progress for the management of HIV-1-infected patients.

In the RT-PCR test, viral RNA is extracted from the patient's plasma and is treated with reverse transcriptase (RT) to convert the viral RNA into cDNA. The polymerase chain reaction (PCR) process is then applied, using two primers unique to the virus's genome. After PCR amplification is complete, the resulting DNA products are hybridized to specific oligonucleotides bound to the vessel wall, and are then made visible with a probe bound to an enzyme. The amount of virus in the sample can be quantified with sufficient accuracy to detect threefold changes.

In the Quantiplex bDNA or branched DNA test, plasma is centrifugated to concentrate the virus, which is then opened to release its RNA. Special oligonucleotides that bind to viral RNA and to certain oligonucleotides bound to the wall of the vessel are added. In this way, viral RNA is fastened to the wall. Then new oligonucleotides that bind at several locations to this RNA are added, and other oligonucelotides that bind at several locations to those oligonucleotides. This is done to amplify the signal. Finally, oligonucleotides that bind to the last set of oligonucleotides and that are bound to an enzyme are added; the enzyme action causes a color reaction, which allows quantification of the viral RNA in the original sample. Monitoring the effects of antiretroviral therapy by serial measurements of plasma HIV-1 RNA with this test has been validated for patients with viral loads greater than 25,000 copies per milliliter.

Further information: Viral load testing

Screening

The South African government announced a plan to start screening for HIV in secondary schools by March 2011  This plan was cancelled due to concerns it would invade pupil's privacy, schools typically don't have the facilities to securely store such information, and schools generally do not have the capacity to provide counseling for HIV positive pupils. In South Africa, anyone over the age of 12 may request an HIV test without parental knowledge or consent. Some 80,000 pupils in three provinces were tested under this programme before it ended.

Diagnosis of Hiv Aids - How to do it

The most common, cost-effective, and accurate method of diagnosing HIV infection is via a blood test that looks for antibodies to HIV. Antibodies are the body's reaction to HIV and other foreign substances. Other methods that can be used are rapid HIV antibody tests that use blood, saliva, or urine. The Food and Drug Administration (FDA) approve all of the above methods.

Before an HIV test can be performed a trained HIV counselor will discuss the test, how to understand its results, and what effect testing will have on your life in detail. You will also be asked to give written permission to be tested.

When someone is tested for HIV, a test called an Enzyme-Linked ImmunoSorbent Assay, or ELISA,

 is performed using a sample of blood obtained from a patient’s vein. If this test is positive a second test called a Western Blot is done, on the same sample of blood, to confirm the positive test. A Western Blot is a blood test to detect antibodies to several specific components of a virus such as HIV. If the initial ELISA test is negative then no further testing is done on that sample, although there are some exceptions to this. Sometimes a test result may be described as “inconclusive”. This means that a diagnosis cannot be made on this sample. It is usually recommended that another sample should be obtained and the test repeated.

The HIV antibody test has limitations. Antibodies to HIV are not made immediately and sometimes can take up to 3 months to develop (the window period). Therefore a negative test does not necessarily rule out a recent infection. If you have had a recent exposure you may need to be retested after 3 months to obtain an accurate result. In a research setting a HIV PCR or viral load test might be performed to detect a recent infection.

Similar antibody tests can be performed using Rapid EIA (ELISA) test on a saliva or blood specimen. This kind of test has been shown to be highly accurate (99.5%) This is comparable to the blood tests mentioned above that are performed in a lab. A positive result from a Rapid EIA test ia considered preliminarily positive and must be confirmed with an ELISA and Western Blot performed in a lab. Results are usually available in 20 minutes.

Hiv Aids Diagnosis -Simple Steps

 Many people newly infected with HIV have no signs and symptoms at all.

 

You can only be certain you have HIV if you have a blood test that looks specifically for the virus.
If you think you might be at risk, you should have a test immediately. The earlier HIV is detected, the more likely it is that treatment will be successful.

Avoiding testing will not make the virus go away, but it will allow the virus to spread in your system and damage your health.
The sooner you get tested, the sooner you can start life-saving treatment and avoid spreading the virus to someone else.
HIV testing is available on the NHS free of charge to anyone. Some clinics can provide test results on the same day the test is taken.

HIV blood test

It can take between three weeks and three months after you have been infected with HIV for the virus to show up in testing.
If your most recent risk of getting HIV was within the last three months you can test straight away, but you will be advised to have another one a few weeks later.
If the test finds no signs of infection, then your test result is “negative”. If the HIV virus has been found in your blood then the test result is “positive”.
Before someone is given a positive result the blood is tested several times to be completely sure.
If you test positive for HIV, you will undergo a number of tests to monitor the progress of the infection to work out when HIV treatment should be started.