According to the latest data from The Joint United Nations Programme on HIV/AIDS (UNAIDS) 2.5 million people were newly infected with HIV in 2007.1 HIV infection in humans is now considered pandemic. UNAIDS and the World Health Organization (WHO) estimate that every day, over 6800 people become infected with HIV and over 5700 people die from AIDS (Acquired Immune Deficiency Syndrome), due to inadequate access to HIV prevention and treatment services1.
HIV infection
HIV is a retrovirus which uses its RNA and the DNA of infected host cells to replicate viral DNA. By targeting the DNA of CD4+ lymphocytes, HIV causes severe damage to the immune system and eventually destroys it. Low levels of CD4+ lymphocytes occur due to direct viral killing of HIV-infected cells, increased apoptosis in the infected cells, and thirdly, HIV-infected CD4+ cells being recognised and killed by CD8 cytotoxic lymphocytes. When CD4+ lymphocytes fall below a critical level the body becomes more susceptible to opportunistic infections, such as pneumonia.
There is currently no vaccine or cure for HIV or AIDS. The only effective method of prevention is avoiding exposure to the virus. Early HIV diagnosis is essential for initiating prompt antiretroviral treatment, known as post-exposure prophylaxis, which is believed to reduce the risk of infection if begun directly after exposure. For those infected with HIV, Highly Active Antiretroviral Therapy (HAART) is the recommended treatment. Although HAART may stabilise a patient’s symptoms, it does not cure the patient or alleviate the symptoms. Increased access to HIV prevention and treatment services would enable patients to appropriately manage their HIV status from the onset.
Assess, Test and Treat
Voluntary HIV counselling and testing (VCT) has become an effective public health tool, providing individuals who might ‘shy’ away from HIV intervention with access to confidential HIV prevention and care.2 Many people who are concerned about HIV and AIDS will not immediately go for testing at their local GP surgery where they are known for fear of stigma and discrimination. Coupled with the anxiety over waiting 24 hours to seven days for test results with a fear that the test may be positive, many people do not return to collect their results, even from GUM clinics where they do have a degree of anonymity.
In May 2007, UNAIDS and the World Health Organization (WHO) released guidelines on HIV testing and counselling in health facilities, recommending VCT alongside provider-initiated testing in all healthcare settings. The VCT model of pre-test discussion, HIV testing, and post-test discussion emphasises the importance of client centred care pathways. By understanding their HIV status, individuals are able to gain early access to specific treatment, care and counselling, prevent transmission, and plan for the future.2
Community testing in action
As one of the first UK charities to be set up in response to the HIV epidemic, the Terrence Higgins Trust is leading the way in implementing rapid point-of-care HIV testing in community settings in the UK with their open access Fast Test clinics.
'At the Terrence Higgins Trust, one of our aims is to get testing out in the community so early detection and prompt management is possible', explains Vanessa Griffiths, Clinical Director at the Terrence Higgins Trust.
'With the appropriate care pathways in place, HIV can be effectively detected in community settings,' continues Vanessa. It is in this way the Terrence Higgins Trust hopes to increase access to local sexual health services and minimise the spread of HIV and AIDS.
Key to this initiative is the innovative use of rapid point-of-care testing for the early diagnosis of HIV. Although enzyme-linked immunosorbent assays (ELISAs) are still the most widely used diagnostic test for HIV, there are new simple/rapid tests available more suited to situations where none or limited laboratory facilities are available. The use of rapid tests increases the capacity to test and provide results within the community setting, and is recommended by the WHO as a component for scaling up HIV testing and counselling services.3
Rapid format tests
Rapid lateral flow HIV tests, such as Determine HIV1/2 from Inverness Medical, have enabled the Terrence Higgins Trust to easily provide one-hour Fast Test HIV clinics across all its UK centres and associate GUM clinics. Assessment, test and results are now possible within the hour.
'The simplicity of a rapid test like Determine HIV1/2 enables us to work in more remote locations and set up clinics where they are needed in the community,' comments Vanessa. With no need for refrigeration, power or water to run the test, Determine is easy to transport and store. 'We don’t need to carry around any clunky kit when we set up a remote clinic now.'
Requiring only a small amount of blood from a finger prick, the Determine HIV1/2 test is quick, safe and virtually painless. Utilising auto-primed lancets which retract immediately after use, the risk of needle stick injury is dramatically reduced whilst the hidden needle means patient refusal on the grounds of needle phobia is virtually non-existent. Once the sample is applied to the simple test card, reliable results are reached in just 15 minutes.
Global appeal
The easy to use Determine rapid test qualitatively detects for both HIV type 1 and type 2 antibodies in human serum, plasma and whole blood samples. Engineered in a robust format for performance anywhere in the world, the Determine test is suitable for use in the areas of the world where HIV is most prevalent, for example sub-Saharan Africa and East Asia. By detecting all known sub types of HIV, Determine can help healthcare workers across the world diagnose individual infection, prevent mother to child transmission, monitor HIV prevalence and screen blood donations.
According to UNAIDS, the number of people using HIV testing and counselling services has quadrupled in the past five years. However, worldwide, only 12% of people who want to be tested are currently able to do so. A recent study by the Terrence Higgins Trust, looking at the success of using rapid HIV tests in non-GUM settings, has shown that 'community based rapid HIV testing has been demonstrated to be effective in identifying HIV infection.'4 VCT and other interventions for HIV prevention, treatment and care, backed by organisations such as WHO, UNAIDS and MDG are starting to show results as downward trends in HIV prevalence are occurring in a number of countries1, with the use of rapid diagnostics playing a significant role.2
References
1. UNAIDS (2007) 2007 AIDS epidemic update
2. WHO (2002) Increasing Access to HIV Testing and Counselling
3. MDG (2007) Millennium Development Goals Report 2007
4. Terrence Higgins Trust (2007) Partnership working to provide community based HIV point-of-care testing
This article is a promotional feature from Inverness Medical.
