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The efficacy of fecal sludge treatment technologies and resource recovery: a systematic review and meta-analysis in Sub-Saharan Africa
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  • Published: 23 January 2026

The efficacy of fecal sludge treatment technologies and resource recovery: a systematic review and meta-analysis in Sub-Saharan Africa

  • Yonas Lamore1,2,3,
  • Shikun Cheng1,3 &
  • Zifu Li1,3 

npj Clean Water , Article number:  (2026) Cite this article

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We are providing an unedited version of this manuscript to give early access to its findings. Before final publication, the manuscript will undergo further editing. Please note there may be errors present which affect the content, and all legal disclaimers apply.

Subjects

  • Diseases
  • Environmental sciences
  • Health care
  • Microbiology

Abstract

Fecal sludge (FS) management in sub-Saharan Africa (SSA) faces financial, technical, and logistical barriers. Despite rapid urbanization, onsite sanitation (OSS) systems remain the primary option for many households, yet often encounter operational challenges across the FS chain, from emptying to disposal, underscoring the need for effective interventions. A systematic review of 93 studies was conducted; 53.8% addressed both treatment and resource recovery, while 20.04% focused exclusively on treatment efficiency. The majority of research was concentrated in Uganda and Burkina Faso, each accounting for 18% of the studies, followed by Kenya at 11%. Treatment outcomes demonstrated significant reductions in Escherichia coli (E. coli) and five-day biochemical oxygen demand (BOD₅), with pooled effect sizes of 1.06 log CFU/100 mL (95% confidence interval [CI]: 0.34 to 1.78) and 181.40 mg/L (95% CI: 131.6 to 231.3), respectively. However, chemical oxygen demand (COD) removal was not statistically significant, with a mean of 69.97 mg/L (95% CI: –20.8 to 160.8). Substantial heterogeneity was observed (I²: 98.6% for BOD₅; 97.2% for COD), indicating significant differences in performance. These findings highlight ongoing limitations in scaling FS treatment technologies and emphasize the urgent need for stakeholder and interdisciplinary collaboration to promote sustainable FS management and resource recovery in SSA.

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Data availability

All data generated during this review are included in this article and its Supplementary Information files.

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Acknowledgements

The authors gratefully acknowledge the support of the National Key Research and Development Program of China (Grant No. 2024YFD1600201) and the National Natural Science Foundation of China (Grant No. 52261145693).

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Authors and Affiliations

  1. School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, PR China

    Yonas Lamore, Shikun Cheng & Zifu Li

  2. College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia

    Yonas Lamore

  3. State Key Laboratory of lron & Steel Industry Environmental Protection, Daxing District, Beijing, PR China

    Yonas Lamore, Shikun Cheng & Zifu Li

Authors
  1. Yonas Lamore
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  2. Shikun Cheng
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Contributions

This systematic review is based on the draft and design by Y.L. and Z.L. All authors collaborated to screen titles, abstracts, and full texts from the search strategy. They removed duplicates and processed the remaining records. Y.L. analyzed the data and wrote the manuscript. Y.L. and S.C. carefully reviewed the papers to choose which ones to include or exclude from the review. Z.L. made the final decisions when disagreements arose. All authors read and approved the manuscript.

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Correspondence to Yonas Lamore or Zifu Li.

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Lamore, Y., Cheng, S. & Li, Z. The efficacy of fecal sludge treatment technologies and resource recovery: a systematic review and meta-analysis in Sub-Saharan Africa. npj Clean Water (2026). https://doi.org/10.1038/s41545-026-00556-9

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  • Received: 14 October 2025

  • Accepted: 12 January 2026

  • Published: 23 January 2026

  • DOI: https://doi.org/10.1038/s41545-026-00556-9

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