Quality Assurance Practices Associated with HIV Viral Load Sample Management among Healthcare Professionals in Machakos County, Kenya

Effective viral load (VL) sample management is critical for reliable laboratory monitoring, timely clinical decision-making and improved patient outcomes. Viral load testing is essential for effective HIV management; however, in Machakos County, Kenya, persistent gaps in sample handling, processing, and transportation have led to rejection rates exceeding 2% annually, peaking at 6.28% in 2023, compromising the quality of the entire process. This study examined the quality assurance practices involved in the viral load sample management. A mixed-methods convergent parallel design was employed, integrating quantitative and qualitative approaches. The study was conducted in public and private health facilities across Machakos County, Kenya, including four viral load hub sites: Machakos Level 5, Matuu Level 4, Athi River Level 4, and Kangundo Level 4 hospitals and their 71 satellite facilities. A total of 205 healthcare practitioners involved in VL sample collection, storage, and transportation participated, representing a 94.04% response rate. Quantitative data were collected through questionnaires, while qualitative data were gathered using semi-structured interviews. Quantitative data were analysed using descriptive statistics, Fisher’s Exact Test, and odds ratios. Qualitative data were analysed thematically using NVIVO version 12, following a six-step framework, and integrated with quantitative findings through triangulation. Ethical approval was obtained from KEMRI-SERU, with clearance from the Machakos County Department of Health. Informed consent and confidentiality were strictly maintained. Remote logging of samples, a critical component of traceability, is reported in 57% of private and 55% of public facilities. Nevertheless, qualitative accounts suggest that electronic logging systems are prone to network failures, data entry errors, and manual overrides: Public facilities demonstrated weaker follow-up mechanisms (7%) compared to private facilities (100%), reflecting significant disparities in tracking systems. Freezing of samples before shipment was reported in 30% of public and 18% of private facilities. However, qualitative findings highlight challenges in maintaining appropriate freezing conditions, with the majority of respondents citing unreliable equipment and inconsistent monitoring of temperature logs. The maintenance of temperature logs was higher in public facilities (62%) compared to private ones (40%), but qualitative data suggests that logs are not consistently reviewed, which may lead to compromised sample quality. The Fisher’s Exact Test indicated a statistically significant relationship between the practice of freezing samples and facility type (p = 0.05), with an odds ratio of 1.90 (95% CI: 0.90–2.80). Quality assurance remained weak, with only 3% of facilities completing documentation correctly and 5% receiving timely test results, while a strong correlation (p < 0.05, r = 0.58) between documentation and sample management effectiveness underscores the need for reinforcing documentation protocols.