The WHO’s ART guidelines have evolved over time as new drugs are developed, knowledge and experience in clinical and programmatic management of HIV have improved, the prevention benefit of ARVs has been better recognized and more funding is available. The guidelines have shifted from “treating the sickest” to “treating all” and from “providing ART for clinical benefit” to “providing ART for both clinical and public health benefits”. These treatment guidelines supported and facilitated the proper management and scale-up of ART using a public health approach towards universal access. This has increased ART coverage at global, regional and national levels; and, the number of new HIV infections and deaths among PLHIV dropped markedly. Early lessons learned in scaling up access to treatment fundamentally altered the public health landscape and influenced subsequent actions towards the goal of universal coverage for ART and ending the epidemic [27–30].
Despite the increase in ART coverage at global, regional and national levels, inequity in ART coverage has remained. What is more worrisome than the existing disparity is the increasing inequity over time in spite of the policies for universal ART coverage. Those populations with better coverage have continued to utilize the services and benefited from the expanded ART initiation guidelines while those which were lagging behind have remained so much more. This phenomenon is also documented as ‘the inverse care law’: the availability of good medical care tends to vary inversely with the need for it in the population served [31].
This inequity is happening and increasing in spite of free ART delivery in these regions and countries. This is observed in regions with predominant heterosexual HIV epidemic, low HIV testing, and weak health systems capacity much more than others. Parity has been achieved between male and female in regions where there is predominantly male epidemic (Western and central Europe and North America, Latin America, Eastern Europe and central Asia, and Asia and Pacific). However, there is a gap in equity between male and female in ART coverage in regions with predominant heterosexual epidemic (West-central Africa, South-east Africa, and Caribbean).
Differences in HIV testing is one of the reasons that ART coverage among men living with HIV (53%) is less than ART coverage among women (65%) globally. Across different geographic and epidemic settings, men are less likely than women to take an HIV test, which is an entry to treatment [32]. In regions where HIV testing is considerably off track— eastern Europe and central Asia, the Middle East and North Africa and western and central Africa—ART coverage is relatively low. HIV testing coverage remains a particular challenge in western and central Africa, where only an estimated 48% of PLHIV knew their HIV status in 2017. On the other hand, in eastern and southern Africa, there has been continued gains in knowledge of HIV status and linkages to care thanks to a combination of strong domestic leadership and resolute global support. Western and central Europe and North America have also achieved a high testing coverage [32]. These together provide evidence for reinforced action for continuum of care towards increased ART coverage and improved equity.
Weak health systems have undermined efforts to scale up HIV testing and ART in certain regions [32]. Inequity in ART coverage between men and women is more prominent in regions with weak health systems capacity (human resource for health per 1000 population, number of hospital beds per 1000 population and UHC index) than others. The World health statistics 2019 indicates that sub-Saharan Africa and the Caribbean have the weakest health systems among the regions in the globe [33]. We argue that this weak health systems capacity, together with the type of the epidemic and other demand-related factors, can explain the inequity in ART coverage between men and women and children and adults. The data from Ethiopia also show that regions with predominant pastoralist and rural populations (living in regions with weaker health systems capacity) have a lower ART coverage and a huge inequity compared to regions with more urban populations (Figs. 2 and 3) [34, 35].
Countries with better ART coverage have also less inequity than countries with poor ART coverage. These countries have implemented certain interventions that enabled them to narrow the inequity gap. In Ethiopia, the framework of primary healthcare, in general, and public health approach to ART delivery, in particular, includes community engagement and participation, task shifting, decentralization, free provision of HIV services, health systems strengthening [17, 36, 37]. The drop in inequity in ART coverage, mainly among the major regions and regions with huge burden of HIV, can be explained by the improved health systems capacity and the approach that the country has been utilizing to increase primary healthcare (PHC) services [34, 35]. In other countries, community-supported models of care, including task shifting to community health workers, have improved HIV testing and treatment [38–40]. Providing support, including accompanied clinic visits and money for transportation, and removing user fees greatly increases HIV testing and treatment [41–43].
The SDG-3 (ensure healthy lives and promote wellbeing for all at all ages) aims to achieve universal health coverage (UHC).[44] This requires countries to provide health services to all, without leaving no one behind. Nevertheless, health services utilization is constrained by factors within and outside the health system. In addition, UHC is a supply-side initiative and requires actions that address the demand side of health services utilization. Hence, it is vital that initiatives towards equity in health also consider socio-economic conditions and make sure that the necessary enabling environment is created. This is possible if countries implement the PHC approach (principles and components) that includes multi-sectoral action. A bolder approach, which fully embraces the Alma-Ata vision of PHC, could deliver substantially greater SDG progress, by addressing the wider determinants of health, promoting equity and social justice [44, 45].
In general, there are several lessons that the UHC movement can learn from the successful ART scale up programs, which have been characterized by free service provision and multi-sectoral response: (1) the plan for UHC will be realized only if there is enabling environment for people to utilize services; (2) achieving UHC requires adequacy of not only the supply side but also that of the demand side of health services delivery and utilization; (3) UHC is not a panacea unless it is implemented according to the principles of PHC, public health approach, and overall socio-economic development; and, (4) monitoring UHC should include not only input and process but also impact indicators.
This study has several limitations. Countries used to reporting the number of people on ART as ever started- or currently- on ART; however, the databases from UNAIDS and WHO do not provide separate figures on these. We contend that the progress towards universal HIV treatment requires data on both ever started (cumulative) and currently on ART; the latter is much more than on the earlier. Similarly, we were not able to compile and present data on second-line ART, as it was either not reported by countries or the report was incomplete. As ART programs mature, the need for second-line ART is increasing. Therefore, countries, UNAIDS and WHO should report on both first- and second-line ART. The other limitation is that the study used data aggregated by WHO regions that links together very different countries, which have varied approaches in scaling up ART delivery. Lastly, we have used a vertical program that has been exceptionally well resourced (with an emergency response) anticipating that the lessons learned can be taken to scale to improve PHC in countries most in need of UHC.