Economic and public health impact of decentralized HIV viral load testing: A modelling study in Kenya

M de Necker, J C de Beer, M P Stander, C D Connell, D Mwai, M de Necker, J C de Beer, M P Stander, C D Connell, D Mwai

Abstract

Kenya has the world's 4th largest HIV burden. Various strategies to control the epidemic have been implemented, including the implementation of viral load (VL) testing to monitor HIV patients on ARVs. Like many resource limited settings, Kenya's healthcare system faces serious challenges in effectively providing quality health services to its population. Increased investments to strengthen the country's capacity to diagnose, monitor and treat diseases, particularly HIV and TB, continue to be made but are still inadequate in the face of global health goals like the UNAIDS 90:90:90 which require scaling up of VL tests amid existing constraints. In Kenya, there is an increase in the demand for VL tests amidst these existing constraints. The GeneXpert system is a diagnostic point-of-care technology that can quantify, amongst others, HIV VL. Currently, GeneXpert technology is widely distributed in Kenya for testing of tuberculosis. This study aimed to determine the economic and public health impact of incorporating VL test modules on the existing GeneXpert infrastructure. Markov models were constructed for different populations (non-pregnant adults, pregnant women and children). The scenarios analysed were 100% centralized VL testing compared to 50% GeneXpert plus 50% centralized VL testing, with time horizons of 5 years for the adult and child populations, and 31 months for the pregnant population. Incremental effectiveness was measured in terms of the number of HIV transmissions or opportunistic infections avoided when implementing the GeneXpert scenario compared to a 100% centralized scenario. The model indicated that, for all three populations combined, the GeneXpert scenario resulted in 117 less HIV transmissions and 393 less opportunistic infections. The cost decreased by $21,978,755 for the non-pregnant and pregnant adults and $22,808,533 for non-pregnant adults, pregnant adults and children. The model showed that GeneXpert would cost less and be more effective in terms of total cost per HIV transmission avoided and the total cost per opportunistic infection avoided, except for the pregnant population, when considered separately.

Conflict of interest statement

The authors’ affiliation with TCD Outcomes Research does not alter our adherence to PLOS ONE policies on sharing data and materials.

Figures

Fig 1. Transition possibilities between main health…
Fig 1. Transition possibilities between main health states.

References

    1. AVERT. HIV and AIDS in Kenya. Cited 6 February 2018.
    1. UNAIDS. Kenya Country Factsheets (2016). .
    1. Lupia R Chien S. HIV and AIDS Epidemic in Kenya: An Overview. J Exp Clin Med. 2012;4(4): 231–234.
    1. Kenya Ministry of Health. Kenya AIDS Response Progress Report 2016. 2016. .
    1. Olney J, Braitstein P, Eaton J, Sang E, Nyambura M, Kimaiyo S, et al. Evaluating strategies to improve HIV care outcomes in Kenya: a modelling study. Lancet HIV. 2016;3(12): e592–e600. 10.1016/S2352-3018(16)30120-5
    1. Maman D, Zeh C, Mukui I, Kirubi B, Masson S, Opolo V, et al. Cascade of HIV care and population viral suppression in a high-burden region of Kenya. AIDS. 2015;29(12): 1557–1565. 10.1097/QAD.0000000000000741
    1. Calmy A, Ford N, Hirschel B, Reynolds S, Lynen L, Goemaere E, et al. HIV Viral Load Monitoring in Resource‐Limited Regions: Optional or Necessary?. Clin Infect Dis. 2007;44(1): 128–134. 10.1086/510073
    1. World Health Organization. Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection. Recommendations for a public health approach. 2016. .
    1. Waruru A, Muttai H, Ng’ang’a L, Ackers M, Kim A, Miruka F, et al. Positive Predictive Value of the WHO Clinical and Immunologic Criteria to Predict Viral Load Failure among Adults on First, or Second-Line Antiretroviral Therapy in Kenya. PLOS ONE. 2016;11(7): e0158881 10.1371/journal.pone.0158881
    1. Sigaloff K, Hamers R, Wallis C, Kityo C, Siwale M, Ive P, et al. Unnecessary Antiretroviral Treatment Switches and Accumulation of HIV Resistance Mutations; Two Arguments for Viral Load Monitoring in Africa. J Acquir Immune Defic Syndr. 2011;58(1): 23–31. 10.1097/QAI.0b013e318227fc34
    1. Roberts T, Cohn J, Bonner K, Hargreaves S. Scale-up of Routine Viral Load Testing in Resource-Poor Settings: Current and Future Implementation Challenges: Table 1. Clin Infect Dis. 2016;62(8): 1043–1048. 10.1093/cid/ciw001
    1. Medecins Sans Frontieres Access Campaign. How low can we go? Pricing for HIV viral load testing in low- and middle-income countries. .
    1. Cepheid GeneXpert IV. Cited 12 March 2018.
    1. Albert H, Nathavitharana RR, Isaacs C, Pai M, Denkinger CM, Boehme CC. Development, roll-out and impact of Xpert MTB/RIF for tuberculosis: what lessons have we learnt and how can we do better? Eur Respir J. 2016;48(2): 516–525. 10.1183/13993003.00543-2016
    1. ZE Currency Converter: KES to USD. .
    1. KNBS–Kenyan National Bureau of Statistics. Economic survey 2017. Cited 29 June 2017.
    1. Berheto TM, Haile DB and Mohammed S. Predictors of Loss to follow-up in Patients Living with HIV/AIDS after Initiation of Antiretroviral Therapy. N Am J Med Sci. 2014;6(9): 453–459. 10.4103/1947-2714.141636
    1. Rachlis B, Genberg B, Musick B, Simiyu G, Hogan J, Braitstein P. Gaps in care among adults receiving HIV care in western Kenya. .
    1. Roberts T. Medecins Sans Frontieres Access Campaign. Will POC make any difference? A perspective on EID, CD4 and viral load. .
    1. Gous N, Scott L, Berrie L, Stevens W. Options to Expand HIV Viral Load Testing in South Africa: Evaluation of the GeneXpert® HIV-1 Viral Load Assay. PLoS One. 2016;11(12): e0168244 10.1371/journal.pone.0168244
    1. Wilson DP, Law MG, Grulich AE, Cooper DA, Kaldor JM. Relation between HIV viral load and infectiousness: a model-based analysis. Lancet. 2008. July 26;372(9635): 314–320. 10.1016/S0140-6736(08)61115-0
    1. Estill J, Tweya H, Egger M, Wandeler G, Feldacker C, Johnson LF, et al. Tracing of Patients Lost to Follow-up and HIV Transmission: Mathematical Modeling Study Based on 2 Large ART Programs in Malawi. J Acquir Immune Defic Syndr. 2014; 65(5): e179–e186. 10.1097/QAI.0000000000000075
    1. Arnedo M, Alonso E, Eisenberg N, Ibáñez L, Ferreyra C, Jaén A, et al. Monitoring HIV Viral Load in Resource Limited Settings: Still a Matter of Debate? PLoS One. 2012; 7(12): e47391 10.1371/journal.pone.0047391
    1. National AIDS & STI Control Program (NASCOP), Ministry of Health Kenya. Guidelines on Use of Antiretroviral Drugs for Treating and Preventing HIV Infection in Kenya. 2016.
    1. National Average Turnaround Time. National AIDS/STD Control Programme (NASCOP). Cited 16 November 2017.
    1. National ACT Dashboard. Cited 1 December 2016.
    1. Kenya AIDS Indicator Survey 2012. Final Report June 2014. Cited 13 March 2018.
    1. Kaplan JE, Hanson DL, Jones JL, Dworkin MS, Adult and Adolescent Spectrum of HIV Disease Project Investigators. Viral load as an independent risk factor for opportunistic infections in HIV-infected adults and adolescents. AIDS. 2001. September 28;15(14): 1831–1836.
    1. Thomas TK, Masaba R, Borkowf CB, Ndivo R, Zeh C, Misore A, et al. Triple-antiretroviral prophylaxis to prevent mother-to-child HIV transmission through breastfeeding—the Kisumu Breastfeeding Study, Kenya: a clinical trial. PLoS Med. 2011;8(3): e1001015 10.1371/journal.pmed.1001015
    1. Cintron, C. Costs of HIV viral load testing using POC and central laboratories: assessing an efficient viral load testing network in Kenya. IAS2017. TULBPED44—Poster Exhibition. Cited 14 November 2017.
    1. Kenya Subsidiary Legislation, 2016. Legal Notice No. 131. The Medical Practitioners and Dentists Board Act. Fees Guidelines for Medical & Dental Practitioners.
    1. Owiti EA and Oleche MA. Costing of Antiretroviral Treatment in Mbagathi District Hospital, Kenya. International Journal of Innovative Research and Development. March 2015;4(3):28–37.
    1. CDC and Kenya Ministry of Health. The Cost of Comprehensive HIV Treatment in Kenya. August 2013. .
    1. Phillips AN, Cambiano V, Nakagawa F, Ford D, Apollo T, Murungu J, et al. Point-of-Care Viral Load Testing for Sub-Saharan Africa: Informing a Target Product Profile. Open Forum Infect Dis. 2016. July 29;3(3):ofw16.
    1. Jouquet G. Economic evaluation of viral load testing and early infant diagnosis in rural Zimbabwe. MSF-OCB December 2016. Cited 25 October 2018.
    1. Ndlovu Z, Fajardo E, Mbofana E, Tatenda M, Garone D, Metcalf C, et al. Multidisease testing for HIV and TB using the GeneXpert platform: A feasibility study in rural Zimbabwe. PLoS One. 2018. March 2;13(3):e0193577 10.1371/journal.pone.0193577
    1. Cintron C, Mudhune V, Avila C, Batuka J, Angira F, Minior T. Costs of HIV viral load testing using POC and central laboratories: assessing an efficient viral load testing network in Kenya 9th International AIDS Society on HIV Science (IAS 2017). 23–26 July 2017. Paris, France.

Source: PubMed

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