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. 2022 Oct 31;16(10):e0010767.
doi: 10.1371/journal.pntd.0010767. eCollection 2022 Oct.

Assessing the efficacy of albendazole against hookworm in Vietnam using quantitative PCR and sodium nitrate flotation

Clare E F Dyer  1 , Naomi E Clarke  1 , Dinh Ng Nguyen  2 , H M P Dilrukshi Herath  3 , Sze Fui Hii  3 , Russell Pickford  4 , Rebecca J Traub  3 , Susana Vaz Nery  1
Affiliations

Assessing the efficacy of albendazole against hookworm in Vietnam using quantitative PCR and sodium nitrate flotation

Clare E F Dyer et al. PLoS Negl Trop Dis. .

Abstract

Preventive chemotherapy (PC), consisting of the regular distribution of anthelmintics to populations or groups of populations at risk, is the primary tool used to control soil-transmitted helminth (STH) infections. This strategy, whilst cost-effective, raises the concern of potential emergence of drug resistance. The efficacy of anthelmintics against STH infections is measured using cure rate (CR) and egg reduction rate (ERR), using microscopy-based techniques such as the Kato-Katz thick smear. However, Kato-Katz has low sensitivity, especially for low-intensity infections, and requires fresh samples that need to be processed quickly. Realtime quantitative PCR (qPCR), which is more sensitive, is emerging as a "gold standard" for STH diagnostics given its higher sensitivity (important in low prevalence settings) and ability to differentiate hookworm species, while sodium nitrate flotation (SNF) may provide a low-cost more sensitive and practical alternative to Kato-Katz in the field. In this study, we examined the efficacy of a locally manufactured brand of albendazole 400 mg ("Alzental") against hookworm in Đắk Lắk province, Vietnam, using both qPCR and SNF. For qPCR, formulae to convert qPCR cycle threshold (Ct) values into eggs per gram of faeces (EPG) were utilised to determine efficacy calculations, and these values directly compared with efficacy values generated using SNF. Factors associated with CR and ERR were examined, and Alzental tablet quality was assessed by comparing with an Australian TGA-approved equivalent "Eskazole" tablet. We observed a CR and ERR of 64.9% and 87.5% respectively using qPCR, and 68.4% and 67.6% respectively using SNF. The tablet composition of Alzental was comparable to Eskazole in terms of active albendazole drug concentration with no evidence of impurities. This study demonstrates that the efficacy of Alzental against hookworm is within the range of previously reported studies for albendazole 400 mg. The study also demonstrates the value of qPCR and SNF as alternatives to standard Kato-Katz methodology for assessment of anthelmintic efficacy.

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Efficacy study design.
*Ineligible due to poor health as determined by the research team.
See this image and copyright information in PMC

References

    1. Vos T, Lim SS, Abbafati C, Abbas KM, Abbasi M, Abbasifard M, et al. Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet. 2020;396(10258):1204–22. doi: 10.1016/S0140-6736(20)30925-9 - DOI - PMC - PubMed
    1. Sakti H, Nokes C, Subagio Hertanto W, Hendratno S, Hall A, Bundy DA. Evidence for an association between hookworm infection and cognitive function in Indonesian school children. Trop Med Int Health. 1999;4(5):322–34. doi: 10.1046/j.1365-3156.1999.00410.x - DOI - PubMed
    1. Stephenson LS, Latham MC, Ottesen E. Malnutrition and parasitic helminth infections. Parasitology. 2000;121(S1):S23–S38. doi: 10.1017/s0031182000006491 - DOI - PubMed
    1. Casulli A. New global targets for NTDs in the WHO roadmap 2021–2030. PLoS Negl Trop Dis. 2021;15(5):e0009373. doi: 10.1371/journal.pntd.0009373 - DOI - PMC - PubMed
    1. World Health Organization. Prevention and control of schistosomiasis and soil-transmitted helminthiasis: report of a WHO expert committee: World Health Organization; 2002. - PubMed

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