Pooled testing conserves SARS-CoV-2 laboratory resources and improves test turn-around time: experience on the Kenyan...

Global efforts to manage the SARS-CoV-2 pandemic depend heavily on widespread testing. However, limited access to reagents, equipment, and trained personnel hampers testing scale. Previous studies have explored pooled testing as a method to increase testing efficiency. While prior research has shown potential benefits of this approach, uncertainty remains about its real-world impact on testing capacity and accuracy. This gap motivated the need to evaluate pooled testing in a resource-constrained setting. No prior work had resolved how pooled testing affects both throughput and sensitivity simultaneously. The challenge lies in balancing resource conservation with diagnostic reliability. This uncertainty drove the investigation into pooled testing on the Kenyan Coast. Understanding this balance is crucial for low-income regions facing similar constraints.

The study aimed to assess the impact of pooled testing on SARS-CoV-2 RT-PCR testing capacity and resource use. Specifically, the goal was to evaluate how a six-sample pooling strategy affects test throughput and reagent consumption. The motivation was to determine whether this method could be applied in low-income settings with limited testing infrastructure. Researchers wanted to quantify the trade-offs between efficiency and sensitivity. The focus was on real-time, operational data from the Kenyan Coast. The study sought to provide evidence for public health decision-makers. The specific problem addressed was the bottleneck in testing due to reagent shortages. The goal was to identify a scalable and sustainable testing approach.

The team implemented a six-sample pooled testing strategy using RT-PCR for SARS-CoV-2. They compared this approach to standard single-sample testing in terms of test capacity and reagent use. RNA extraction and RT-PCR stages were monitored for resource consumption. Testing throughput was measured before and after the implementation of pooling. The study tracked the number of tests processed per day as a key performance indicator. They also recorded the number of reagent kits used at each stage. Sensitivity was assessed by comparing cycle threshold values between pooled and single samples. The data were analyzed to determine the overall impact on testing efficiency.

Adopting the six-sample pooled testing strategy increased RT-PCR testing capacity by approximately 100%. The team observed a 50% reduction in the number of SARS-CoV-2 test kits used at both RNA extraction and RT-PCR stages. This resource saving was consistent across both testing phases. However, the sensitivity of the tests slightly decreased with pooled samples. The cycle threshold value (ΔCt) was 1.59 higher for pooled samples compared to single ones. This suggests a minor reduction in detection sensitivity. The trade-off between resource efficiency and sensitivity was quantified. The results highlight the potential of pooled testing to enhance testing capacity while conserving resources.

The study found that pooled testing can significantly increase SARS-CoV-2 testing capacity in low-income settings. The six-sample strategy reduced reagent use by half at both testing stages. This approach may help alleviate resource constraints in public health laboratories. However, the slight decline in sensitivity must be considered when implementing this method. The authors suggest that pooled testing is a viable strategy for improving test throughput. They emphasize the importance of balancing resource conservation with diagnostic accuracy. The findings may inform public health policies in resource-limited regions. The authors propose that pooled testing could be adapted to other settings facing similar challenges.