What is a 4th gen HIV test?

The AFA Anonymous Testing Services have been providing simple, quick and affordable HIV testing utilising 3rd generation test kits for both blood and oral fluids. In an effort to improve our services, the AFA anonymous testing clinic and mobile testing services will be introducing the 4th generation test kits.


What’s the difference between 4th and 3rd gen test kits?

Fourth-generation tests kits look for both antibodies AND antigens.

  • P24 Antigens are proteins on the surface of the HIV particle.
  • Antibodies are produced by the immune system in response to the HIV antigens. They fit together like a lock and key.

 

Immune response of HIV infection

3rd generation tests take 6-8 weeks and only tests for antibodies.

4th generation tests are accurate 14 days after exposure, because this is when the p24 antigen becomes high enough to measure; effectively reducing the window period by average of 14 days.

A negative result at 28 days is good news but it is not conclusive. UK guidelines (BASHH) say that an early negative result at 28 days (1 month) needs to be confirmed with a second test 90 days (3 months) after the exposure.

Ask for the 4th Generation Test at one of the following services provided by AFA at $40 per test.

Click to learn more about each service.


More about p24 antigen

One distinctive HIV antigen is a viral protein called p24, a structural protein that makes up most of the HIV viral core, or ‘capsid’. High levels of p24 are present in the blood serum of newly infected individuals during the short period between infection and seroconversion, making p24 antigen assays useful in diagnosing primary HIV infection.

Antibodies to p24 are produced during seroconversion, rendering p24 antigen undetectable after seroconversion in most cases. Therefore, p24 antigen assays are not reliable for diagnosing HIV infection after its very earliest stages. However, HIV infection can be reliably diagnosed earlier with combined antibody/antigen tests than with purely antibody-detecting tests, and fourth-generation antibody/antigen tests are now the standard screening assay in the UK and some other countries.

More about HIV antibodies

Antibodies are protein molecules produced by the immune system in response to allergens, infectious organisms (including viruses, bacteria, fungi and parasites), and sometimes (in autoimmune disorders) the body’s own components.

Infectious organisms and allergens display characteristic proteins called antigens. The immune system recognises and responds to antigens by generating corresponding antibodies. An antibody is designed to ‘fit’ only one particular antigen, rather like a key in a lock. (The word ‘antigen’ in fact derives fromantibody generation.) By locking on to the antigen-bearing intruders, antibodies aim to render them harmless, to kill them outright, or to ‘tag’ them for destruction by other components of the immune system.

One or two weeks after initial exposure to HIV, antibodies to HIV antigens begin to appear in the blood, at concentrations which continue to increase for several more months. These antibodies persist for life, providing distinctive markers which can be identified by HIV screening tests

Novel immune-suppressant vaccine

A novel and relatively simple vaccine that can be administered orally has managed to completely block rectal infection with SIV, the monkey equivalent of HIV, in rhesus macaques and produced rapid re-suppression of viral load in monkeys who were previously infected with SIV.

The vaccine, whose success at blocking infection was described by its own designers as ‘surprising’ and ‘unexpected’, appears to work by stimulating the production of a previously unknown group of CD8 T-cells that stopped the monkeys’ CD4 cells from recognising SIV as a foreign invader, thereby preventing an immune response to SIV. This suppressant effect – which works in the opposite way to a traditional vaccine – means that the SIV is deprived of the SIV-specific immune-activated CD4 cells it needs in order to proliferate and establish an infection in the body.

The vaccine consisted of inactivated SIV administered alongside doses of familiar bacteria – in the first case the TB-suppressant bacterium BCG, and subsequently with gut bacteria of the Lactobacillus genus, including one type commonly used in probiotic supplements. This suggests that if human studies replicate the success seen in monkeys (by no means assured in vaccine studies) the vaccine could be administered in a drink.

Two initial safety trials are now planned in humans. In one, HIV-negative volunteers at low risk of HIV will be given the vaccine to see if it stimulates the same immune- and virus-suppressant responses. In the other, HIV-positive volunteers on fully-suppressive antiviral therapy will be given the vaccine and then taken off ART six months later if test tube results suggest the vaccine has produced such responses.

First published – Aug 26 2014 – AIDS Map

AIDS 2014 : Closing

At the closing ceremony, the organisers reflected upon the accomplishments and tragedy that contributed to the make-up of a conference where, according to Chris Beyrer, the president of the International AIDS Society,

“ the conference than anywhere else before where the separations betweens scientists, clinicians… and people living with HIV and activists truly went away.”.

Melbourne Lord Mayor Robert Doyle said that the way the city had embraced Australia’s largest-ever health conference touched his heart and recounted stories involving delegates being at the receiving end of acts of kindness by Melburnians.

After Barré-Sinoussi passed on her best wishes to the first openly-gay president of the International AIDS Society, Chris Beyrer, the New Yorker thanked his colleague and Melbourne for hosting the conference and praised Australia’s response to the epidemic while also highlighting it could continue to show the way in the future.

“The whole [HIV and AIDS] movement is grateful to Melbourne, grateful to Australia and we really hope that the Melbourne Declaration is going to be a living document that is going to continue to inform our response, “ Beyrer said.

Beyrer turned his attention towards the next International AIDS Conference to be held in Durban, South Africa in 2016, the first in the sub-continent since 2000, and welcomed the first female African co-chair of the event.


Related Speeches from the Closing Session

AIDS 2014 : Bill Clinton’s speech

Former US president Bill Clinton has told a world AIDS conference in Melbourne that an AIDS-free generation is within reach.

Mr Clinton addressed the audience about the future for the treatment and prevention of HIV and AIDS. He said every year another 2 million people are infected with HIV, including 20,000 children a month. But he said achievements made in the fight against AIDS should not be an excuse for people to rest on their laurels.

“The AIDS-free world that so many of you have worked to build is just over the horizon. We just need to step up the pace,” he said.

“We are on a steady march to rid the world of AIDS.” Mr Clinton said one of the biggest challenges the international community faces was the early detection of HIV. “New data from 51 countries suggests 70 per cent of HIV-related deaths could have been prevented.” he said. “The evidence continues to build that early treatment helps prevent further transmission.”

His speech was briefly interrupted by protesters calling for new financial taxes to support the fight against AIDS. “Give them a hand and ask them to let the rest of us talk,” Mr Clinton said as the protesters continued to interrupt his speech.

Read on…


 

First Published on ABC.net.au

Breaking : HIV Kick Out From Infected Cells

The technique addresses the problem of hidden reservoirs of HIV in the body, and could herald a new way of battling the viral infection

Once HIV invades the body, it doesn’t want to leave. Every strategy that scientists have developed or are developing so far to fight the virus – from powerful anti-HIV drugs to promising vaccines that target it – suffers from the same weakness. None can ferret out every last virus in the body, and HIV has a tendency to hide out, remaining inert for years, until it flares up again to cause disease.

None, that is, until now. Kamel Khalili, director of the Comprehensive NeuroAIDS Center at Temple University School of Medicine, and his colleagues took advantage of a new gene editing technique to splice the virus out of the cells they infected – essentially returning them to their pre-infection state. The strategy relies on detecting and binding HIV-related genetic material, and therefore represents the first anti-HIV platform that could find even the dormant virus sequestered in immune cells.

Read on…


 

First Published on Time.com – July 21 2014

AIDS researcher amongst those on MH17

AFA expresses it’s deepest condolences and sincere sympathies to the families and loved ones of all on board flight MH17. 100 AIDS Conference delegates heading to Melbourne lost their lives in this unfortunate tragedy. It is indescribably painful and regrettable for all of us. As we grief with the community, our thoughts and prayers are with their families and loved ones.

Among them were professor Joep Lange from the Netherlands, Lucie van Mens, and Martin de Schutter from AIDS Action Europe and Glenn Thomas from the World Health Organisation.

Lange, an expert in the field of medicinal AIDS therapy, founder of PharmAccess Foundation and Former International AIDS Society head has strongly advocated for patients in Africa to gain improved access to effective drugs.

“If we are able to deliver cold Coca Cola and beer to the most remotes regions in Africa, it shouldn’t be impossible to do the same with drugs.”
– Lange, 2002, AIDS summit in Barcelona.


Related News Reports

AIDS 2014 : Opening

In the crowded plenary room, AIDS 2014 opened on 20 July 2014 in Melbourne, a ceremony that was bitter sweet and sombre mood in light of the MH17 tragedy. Hosted by Chinese journalist and UN Goodwill Ambassador James Chau, began with Lambert Grijns, Dutch ambassador for sexual health and HIV rights, paying respect to his fellow delegates who died on the Malaysian Airlines flight that was shot down in Ukraine on Friday.

14 - 1The ceremony continued with speakers highlighting the need to step up the pace on the global fight against HIV and AIDS stigma and discrimination, and to raise awareness and education on HIV prevention and treatment.

Ayu Oktariani from Indonesia led a procession of people living with HIV from South East Asia and the Pacific in traditional dress.She spoke of her personal experiences of being diagnosed with AIDS and the stigma and discrimination she faced.

“Many of us got HIV because we did not have the means to protect ourselves,” she said.

She went on to rally for people living with HIV and AIDS to get involved, highlighting that it cannot be just left to science.

“We need people living with HIV in the response,” she said.


Related Speeches from the opening Session

Consolidated guidelines (UNAIDS 2014)

People at higher risk of HIV infection are not getting the health services they need, according to a new report by the World Health Organization entitled Consolidated guidelines on HIV prevention, diagnosis, treatment and care for key populations.

Released on 11 July, the publication warns that failure to provide adequate

 

HIV services for key groups, such as men who have sex with men, people in prison, people who inject drugs, sex workers and transgender people, threatens the global progress of the HIV response.

The consolidated guidelines outline the steps for countries to take to reduce new HIV infections and increase access to HIV testing, treatment and care services by populations at higher risk. The report aims to provide a comprehensive package of evidence-informed HIV-related recommendations for all populations, increase awareness of the needs of and issues important to key populations, improve access, coverage and uptake of effective and acceptable services, and catalyse greater national and global commitment to adequate funding and services.

“Failure to provide services to the people who are at greatest risk of HIV jeopardizes further progress against the global epidemic and threatens the health and well-being of individuals, their families and the broader community.”

Gottfried Hirnschall, Director of the HIV Department at the World Health Organization


 

First published – July 11 2014

AIDS 2014 Melbourne Declaration

This declaration affirms that non-discrimination is fundamental to an evidence-based response to HIV and effective public health programmes.

aids-2014-declaration“The enforcement of discriminatory and criminalising laws and policies against Key Affected Populations is deeply alarming.” said Professor Françoise Barré-Sinoussi, AIDS 2014 International Chair, President of the International AIDS Society (IAS) and Director of the Regulation of Retroviral Infections Unit at the Institut Pasteur in Paris. “Such practices clearly violate basic human rights and heavily undermine HIV programmes by posing barriers to access to HIV prevention, treatment, and care. With the declaration we want to reiterate that every individual has the same rights and dignity as everyone else as we are born equal and part of the human family. ”

All individuals and organizations involved in the global response to HIV and AIDS are encouraged to visit and sign the declaration at www.aids2014.org/declaration.aspx and to share it with their networks.

 

“If we really want to change the course of HIV we must make sure that nobody is left behind. AIDS 2014 will be a truly global, inclusive conference and will reflect the principles of the declaration” commented Professor Sharon Lewin, Local Co-Chair of AIDS 2014, Head of the Department of Infectious Diseases, Alfred Hospital and Monash University and Co-Head of the Centre for Biomedical Research at the Burnet Institute in Melbourne.

Better HIV Testing Options

First Published on HIV Plus Mag, By Dr. Gerald Schochetman, June 27 2014

National HIV Testing Day reminds us that every nine and a half minutes, someone in the United States is infected with HIV, which is why we need to empower ourselves with the latest tools at our disposal.

It has been more than 30 years since HIV was first identified, and we have changed the course of this deadly disease. Breakthroughs in treatment in the mid-1990s have led to longer and healthier lives for people living with HIV and have resulted in dramatic declines in HIV-related deaths. HIV prevention has also saved countless lives—including an estimated 350,000 in the United States alone.

So why are many public health experts calling for an update to current HIV testing guidelines, that at least in part, depend on 25-year-old testing technology?

Read More

Our Mobile Testing Service uses the new HIV combo test (Antigen & Antibodies)