Field Validation of Triplex Assay for HIV Diagnosis, Serotyping & Detection of Recent Infection Using the 2018 Nigeria Aids Indicator and Impact Survey Samples- Phase II

  • January 31, 2025
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  • 4 min read

Ongoing efforts to validate a novel bead-based multiplex assay and rapid tests in Nigeria to address the need for several assays to diagnose/confirm HIV serology andperform HIV typing have progressed to its second phase. Implementing partners of the Optimizing HIV Diagnosis project including the Federal Ministry of Health and Social Welfare, (FMoH), National AIDS, Viral Hepatitis and STI’s Control Program (NASCP), Nigeria Center for Disease Prevention and Control (NCD), African Field Epidemiology Network (AFENET), and APIN Public Health Initiative have collaborated to validate the multiplex assay and rapid test to address the large sample volume requirements and multiple testing steps that results to lengthy, laborious, and costly process of diagnosis.

The Multiplex Bead Assay (MBA) laboratory of the National Reference Laboratory (NRL), Nigeria Centre for Disease Control and Prevention (NCDC), Gaduwa is where the tests are conducted. In phase one of the project, the objective was to test HIV-negative samples (n=25,000) from NAIIS-negative samples with a more sensitive assay, the Multiplex Bead Assay (MBA). The initial observation indicated that some HIV-negative samples (n=50) from NAIIS tested positive with the MBA assay and if these samples also contained ARVs.

In the second phase of testing, a subset of the initial sample size will be further subjected to additional testing using the Nigeria HIV testing algorithm and enzyme immunoassays at the national reference laboratory to understand the statuses of these samples better.

Ado Abubakar, Lab Manager Multiplex Bead Assay, stated, “These tests are of great public health importance for the fact that ordinarily, assays can pick antigens or antibodies or both, but beyond that, these assays can do the serotyping, differentiate between type 1 and type 2. It is also able to differentiate between recent and established infections. That is why it is a triplex technology, and probably the first of its kind developed by USCDC”

In 2017, the United States Centers for Disease Control and Prevention (CDC) HIV Serology & Incidence Team, developed the multiplex bead-based assay that combines HIV diagnosis, serotyping, and recency classification, all in a single assay. In the phase 1 of the project, a team of Lab scientists from the USCDC International Laboratory Branch joined AFENET scientists in conducting the tests. Robert Domaoal, leader of the team from USCD  expressed gratitude for the support received from AFENET, stating, “we are impressed by the success of the competency assessments of AFENET scientists testing at the laboratory. Everyone has been great”. He expressed confidence that the team would conclude the testing of all 25,000 HIV-negative samples within the stipulated time.

OluwaseunAkinmulero, Deputy Manager Multiplex Bead Assay Laboratory, a public health specialist stated, “We have scientists, public health officers, and experience data managers. We have people that worked on the multiplex technology from inception in Nigeria, it’s been very robust in terms of people coming in with different experiences. New team members are trained, so there’s been a lot of capacity building”

Dr Patrick Nguku, Regional Coordinator of AFENET on an earlier visit to the lab enthused optimism on the outcome of the project andpraised the Laboratory Project lead, Davis Ashaba – Senior Laboratory Scientist/Lab for excellent leadership. He also commended the AFENET scientists for their competence and dedication.

AFENET was a consortium member of the Nigeria AIDS Indicator and Impact Survey (NAIIS) conducted in 2018. Prior to NAIIS, AFENET implemented the KadunaAIDS Indicator and Impact Survey, a precursor to NAIIS.

Nigeria’s HIV epidemic ranks as the second highest across the world, with over 1.9 million people currently living with HIV, with current evidence revealing incidence as 8.0 per 10,000 persons across both genders and age groups, and a current prevalence of 1.4% among adults aged 15–49 years.