The majority of patients starting to receive antiretroviral therapy will be recruited from settings where opportunistic infections are already apparent: tuberculosis treatment services, acute medical care in outpatient departments and hospital wards, and home-based care programmes. Increasingly, patients will be identified as HIV-positive in other settings where testing is offered, such as free-standing voluntary counselling and testing centres, maternal and child health clinics where prevention of mother-to-child transmission programmes are in place, and clinics dealing with sexually transmitted infections. Patients identified at these entry points, even though asymptomatic and not eligible immediately for antiretroviral therapy, need to be inducted into a continuing review process. This will enable their opportunistic infections to be correctly diagnosed and treated. It will also ensure that they are prepared psychologically and socially for the time when they will receive treatment and that it is initiated at the right time. This continuing care might be provided in dedicated HIV clinics, in clinics specializing in tuberculosis or sexually transmitted infections, in general medical clinics, or in home care programmes. Making this continuum of services available to every community will be a tremendous challenge, and one for which all countries will need considerable assistance.
There are also geographical and institutional dimensions to the challenge of scaling up provision of antiretroviral therapy. Previously, the locations in which treatment has been provided have been predominantly urban and the facilities have been mostly hospitals. This was natural during the pilot phase, which demonstrated the feasibility of the therapy in resource-poor settings, and it remains rational to expand the service delivery network by working downwards through the hierarchy of facilities from the better-endowed to the more basic. Population coverage on the scale envisaged, however, requires a dramatic expansion in the number of service delivery points, and that inevitably means expanding into the geographical periphery of each country and district and into lower-tier facilities which lack the staff and resources of the pilot sites. This dissemination of service delivery points is also important for geographical equity of access to services. Fortunately, some pilot sites have developed services on a district-wide basis and demonstrated the feasibility of delegating tasks to mid-level health workers in primary care facilities (9). The antiretroviral therapy treatment guidelines developed by WHO assume a pattern of services at district level whereby there is a central facility (hospital or major health centre) connected to a network of ambulatory care facilities by cross-referral of patients and specimens, and supportive supervision of the less skilled staff customarily found at lower-tier facilities (10).
Dissemination of service provision into primary care facilities may increase the distance to laboratories and skilled diagnosticians, but it reduces the distance (geographical and social) to the communities from which the patients come, which are themselves a crucial resource for care and treatment. Since a high level of adherence to treatment is a condition for viral load suppression, the proximity of drug re-supply and the support of community members in adherence and other tasks (as discussed in Chapter 3) are important for programme success.