Value of Confirmatory Testing of Early Infant Diagnosis for HIV

Research published in PLoS Medicine focused on the value of confirmatory testing for human immunodeficiency virus (HIV) in infants when using nucleic acid amplification tests (NAATs) due to false-positive rates of more than 10%.¹

HIV infection in infants is still a major concern in low-income countries, and early detection is essential for exposed infants. Policy surveys show that 38% of high-burden countries do not include confirmatory testing in their guidelines, often due to high costs associated with the testing. Researchers therefore used a computer simulation model of HIV infection to investigate the clinical and economic outcomes of early infant diagnosis (EID) with and without confirmatory testing.

The Cost-Effectiveness of Preventing AIDS Complications (CEPAC)—Pediatric model was used to simulate cohorts of HIV-exposed infants in South Africa and follow them from birth to death. One cohort received 6-week EID testing without confirmatory testing and the other cohort underwent 6-week EID testing with confirmatory testing. Cohort input data were obtained from published trials on HIV transmission, disease progression, and antiretroviral treatment outcomes in sub-Saharan Africa, and NAAT specificity was modeled after a 2015 WHO meta-analysis.²

Lifetime cost of an HIV-exposed infant was US $1830 without confirmatory testing and US $1790 with testing. The use of confirmatory testing would be anticipated to save more than US $1,050,000 by averting unnecessary antiretroviral therapy and other HIV treatments. Even with many variations to the model parameters, confirmatory testing remained cost-effective.

The investigators concluded that confirmatory testing should be implemented in all cases using virologic assays for the cost-saving benefits alone; however, there is also likely to be positive health outcomes by avoiding medical toxicities and treatment-related complications in patients receiving false-positive results, although this scenario was not explicitly tested here. 

References

1. Dunning L, Francke JA, Mallampati D, et al. The value of confirmatory testing in early infant HIV diagnosis programmes in South Africa: a cost-effectiveness analysis. PLoS Med. 2017;14:e1002446.
2. Mallampati D, Ford N, Hanaford A, Sugandhi N, Penazzato M. Performance of virological testing for early infant diagnosis: a systematic review. J Acquir Immune Defic Syndr. 2017;75(3):308-314.