Cat.: HP40-12/2007 ISBN: 978-0-662-49711-0 |
Research Paper prepared for the
International Public Health Dialogue
on HIV Testing and Counselling
Toronto, August 17, 2006
The Public Health Agency of Canada wishes to acknowledge the work of the Forum for Collaborative HIV Research in preparing this paper for the International Public Health Dialogue on HIV Testing and Counselling.
The Agency would also like to acknowledge the contribution of the following steering committee members who provided valuable comments on this report:
Dr. Veronica Miller, Forum for Collaborative HIV Research
Dr. Françoise Hamers, European Centre for Disease Prevention and Control
Dr. Anindya Chatterjee, UNAIDS
Ms. Seema Paul, UNAIDS
Public Health Agency of Canada Officials
Two growing bodies of evidence contribute to the importance of reaching a greater portion of people who are HIV positive, but do not know their status. First, people with HIV can greatly benefit from treatment that is initiated before they develop physical symptoms of HIV disease. Second, people who know they are HIV seropositive are more likely to adopt safer sexual and/or injecting drug practices in order to protect their partners from becoming infected. When people know their serostatus and have access to care and information, they are better able to cope with the diagnosis; manage their illness; prevent transmission to others; and live satisfying and healthy lives (Ontario Ministry of Health, 1995).
In considering approaches to reaching people unaware of their HIV status, two populations need to be taken into account: people who do not know that they are infected because they generally do not access testing, and people who may have been tested, but tested negative because they are in the acute phase of infection, prior to seroconversion. Due to the high level of infectiousness during acute infection, approaches that increase the efficiency of identifying those in the acute phase could potentially have a significant impact on the epidemic. Increasing testing rates among people who generally do not access testing, however, is a much greater challenge, as will be described in this review.
There are several different approaches to HIV testing and counselling. Public health decisions regarding these approaches need to consider a range of factors. Universal screening has not been considered cost-effective in lowprevalence parts of a population, given the resources required to administer all aspects of HIV testing and counselling. Moreover, even in largescale testing, the low percentage of false-positives has usually been deemed too high. The alternative, targeting at-risk people for testing and counselling, has had varying results but always leaves some proportion of seropositive people unidentified. As testing and counselling become more affordable and available and the known advantages of increasing HIV testing and counselling begin to outweigh the disadvantages, old assumptions are being questioned and new approaches are being considered.
It will be crucial for these approaches to be grounded in sound public health practice that respects, protects, and fulfills human rights norms and standards. The voluntary nature of testing must remain at the heart of all HIV policies and programs to comply with human rights principles and to ensure sustained public health benefits.
The purpose of this background paper is to set the stage for a dialogue about the issues related to testing and counselling. Section One provides the historical background regarding HIV counselling and testing primarily in middle- and high-income countries. It discusses the ethical, social and legal contexts within which the predominant model, voluntary counselling and testing (VCT) often with partner notification, has developed.
Section Two briefly outlines what is known about the number of people unaware of their HIV status, providing some figures from countries that have calculated its possible magnitude.
Section Three describes how counselling and testing is currently being done. Special populations who are vulnerable to both HIV and HIVrelated stigma and discrimination are discussed. New counselling and testing approaches including rapid testing and provider-initiated testing and counselling are also discussed. Section Four summarizes the body of knowledge that has developed regarding the effectiveness of counselling and testing including costeffectiveness modeling. Section Five outlines some of the areas in which further research would help close the gaps in knowledge about how to reach people unaware of their HIV status.
As the focus of this paper is HIV testing and counselling as it relates to people unaware of their HIV status, the paper will primarily be concerned with reaching individuals through their contact with health care systems and through other more communitybased approaches. The issues regarding the testing and counselling of pregnant women in order to prevent perinatal transmission are presented because much of the research related to screening has been in the context of perinatal testing and counselling. The primary focus of this paper, however, is HIV testing and counselling as it relates to reaching people who do not have easily identifiable institutional affiliations.