Improving the quality of HIV rapid testing in Ghana using the dried tube specimen-based proficiency testing program

Abstract

Background: The introduction of human immunodeficiency virus (HIV) antibody rapid testing (RT) in resource-limited settings has proven to be a successful intervention to increase access to prevention measures and improve timely linkage to care. However, the quality of testing has not always kept pace with the scale-up of this testing strategy. To monitor the accuracy of HIV RT test results, a national proficiency testing (PT) program was rolled out at selected testing sites in Ghana using the dried tube specimen (DTS) approach.

Methods: Between 2015 and 2018, 635 HIV testing sites, located in five regions and supported by the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), were enrolled in the HIV PT program of the Ghana Health Service National AIDS/STI Control Programme. These sites offered various services: HIV Testing and Counselling (HTC), prevention of mother-to-child transmission (PMTCT) and Antiretroviral Treatment (ART). The PT panels, composed of six DTS, were prepared by two regional laboratories, using fully characterized plasma obtained from the regional blood banks and distributed to the testing sites. The results were scored by the PT providers according to the predefined acceptable performance criteria which was set at ≥ 95%.

Results: Seven rounds of PT panels were completed successfully over three years. The number of sites enrolled increased from 205 in round 1 (June 2015) to 635 in round 7 (December 2018), with a noticeable increase in Greater Accra and Eastern regions. The average participation rates of enrolled sites ranged from 88.0% to 98.0% across the PT rounds. By round 7, HTC (257/635 (40.5%)) and PMTCT (237/635 (37.3%)) had a larger number of sites that participated in the PT program than laboratory (106/635 (16.7%)) and ART (12/635 (1.9%)) sites. The average testing performance rate improved significantly from 27% in round 1 to 80% in round 7 (p < 0.001). The highest performance rate was observed for ART (100%), HTC (92%), ANC/PMTCT (90%) and Laboratory (89%) in round 5.

Conclusion: The DTS PT program showed a significant increase in the participation and performance rates during this period. Sub-optimal performances observed was attributed to non-compliance to the national testing algorithm and testing technique. However, the implementation of review meetings, peer-initiated corrective action, supportive supervisory training, and mentorship proved impactful. The decentralized approach to preparing the PT panels ensured ownership by the region and districts.

Fig 1. Overall study statistics of HIV testing sites from round 1–7.

Trends of HIV testing sites enrolled (N = 635) and participated in the proficiency testing (PT) program, their participation and performance rates between June 2015 and December 2018 (PT rounds 1 to 7) in 5 regions in Ghana.

Fig 2. Participation rate by type of testing facility from round 1–7.

High participation rates were observed among all testing sites. HTC and ART testing sites maintained consistent participation rates throughout the period of the study whilst Laboratory and PMTCT testing sites performance rates fluctuated within the same period.

Fig 3. Reasons for unsatisfactory performance by testing sites.

Unsatisfactory performance during the study period was attributed to a number of reasons with results misinterpretation being the highest. There was a major stockout of HIV tests kits in round 1 and minor ones recorded in rounds 5, 6 and 7. Testers not following the national HIV testing algorithm also attributed to non-performance throughout the study.