Establishment of an External Quality Assessment Scheme for Clinical Parasitology Diagnostics in India: Four years of experience (2022-2025)

Introduction: Microscopy remains an important catch all diagnostic tool for parasite detection in clinical settings. Although relatively low-cost in endemic settings, it requires sustained technical skills. To enhance microscopy-based diagnostic capabilities in India, a parasitology External Quality Assessment Scheme (EQAS) was launched in 2022. Materials/Methods: An online survey was conducted to plan the diagnostics scope for a clinical parasitology EQAS in India. In the EQAS, well-characterized proficiency testing material was distributed biannually, with two challenges/cycle and scoring provided based on established criteria. After three years, an online feedback survey was conducted to evaluate the perceived effectiveness of the scheme. Results: The diagnostic scope assessment (n=78 laboratories) indicated microscopy as the commonest technique for parasite identification (100%) and molecular diagnostics are sparsely available (3.8%). Of the eight PT cycles conducted, high competence (>80%) was observed for endemic parasites, Giardia duodenalis (90% in 2022 & 97% in 2025), Echinococcus granulosus (96%), Trichuris trichiura (95%), Taenia spp., (88.6%), Strongyloides stercoralis (87%), Hymenolepis nana (84%), Ascaris lumbricoides (82.6%), Cystoisospora belli (81%), and Cryptosporidium spp. (80%). Challenges noted were in the identification of uncommon or non-endemic parasites - Paracapillaria philippinensis (58%), Clonorchis sinensis (72%), Hymenolepis diminuta (63%) and in samples with two parasites, only 27% reported both accurately. Feedback survey indicated >95% satisfaction with reporting and educational materials among respondents, and 90% requesting for 3 PT cycles/year. Conclusion: The parasitology EQAS program tailored for Indian laboratories led to measurable improvement in diagnostic performance, and participants feedback indicated a positive impact on parasitology diagnostics and education.