Skip to main content

BRIEF RESEARCH REPORT article

Front. Malar.
Sec. Vectors
Volume 2 - 2024 | doi: 10.3389/fmala.2024.1507392
This article is part of the Research Topic Combating Threats to Global Malaria Control View all 4 articles

Comparative efficacy of Vector Guard® to Olyset® Plus insecticide treated nets against strongly pyrethroid-resistant Anopheles arabiensis in experimental huts in Tanzania

Provisionally accepted
Jane Johnson Machange Jane Johnson Machange 1,2*Emmanuel Mbuba Emmanuel Mbuba 1,3,4*Seth R. Irish Seth R. Irish 3,4,5Johnson Kyeba Swai Johnson Kyeba Swai 1,3,4Watson Ntabaliba Watson Ntabaliba 1Noely Otto Makungwa Noely Otto Makungwa 1Safina H. Ngonyani Safina H. Ngonyani 1Ahmadi Bakari Mpelepele Ahmadi Bakari Mpelepele 1,2Olukayode G. Odufuwa Olukayode G. Odufuwa 1,3,4,6Ummi Abdul Kibondo Ummi Abdul Kibondo 1Sarah Moore Sarah Moore 1,2,3,4
  • 1 Ifakara Health Institute, Ifakara, Tanzania
  • 2 Nelson Mandela African Institution of Science and Technology, Arusha, Arusha, Tanzania
  • 3 Swiss Tropical and Public Health Institute (Swiss TPH), Basel, Basel-Landschaft, Switzerland
  • 4 Faculty of Science, University of Basel, Basel, Switzerland
  • 5 World Health Organization (Switzerland), Geneva, Geneva, Switzerland
  • 6 London School of Hygiene and Tropical Medicine, University of London, London, London, United Kingdom

The final, formatted version of the article will be published soon.

    ITNs with pyrethroids and piperonyl butoxide (PBO) synergists were developed to overcome metabolic pyrethroid resistance mechanisms. To demonstrate its potential efficacy for public health use, a comparative efficacy study was conducted to evaluate Vector Guard® relative to Olyset®Plus (a pyrethroid PBO ITN, proven to reduce malaria transmission more effectively than pyrethroid ITNs) and Royal®Sentry 2.0 in experimental huts in Tanzania. An experimental hut trial using two blocks of 7 x 7 Latin square design was conducted over seven rounds (49 nights). Treatments were rotated at the end of each round and volunteers rotated nightly within one block. Both unwashed and 20-times-washed nets of each type were evaluated, alongside an untreated net used as a negative control. The primary endpoint was the proportion of Anopheles arabiensis that died within 24 hours, and the secondary endpoint was the proportion of blood-feeding. Data were analysed using binomial logistic regression with fixed effects using a 7% non-inferiority margin. Pooled results showed that Vector Guard® was non-inferior and superior to Olyset®Plus, with higher mortality for Vector Guard®. Both pyrethroid-PBO nets were superior to Royal Sentry® 2.0 in terms of mosquito mortality. For the secondary blood feeding endpoint, Vector Guard® was also non-inferior to Olyset® Plus. Vector Guard® showed similar efficacy to Royal Sentry®2.0 in reducing the proportion of mosquito blood-feeding. Vector Guard® demonstrated superior mosquito mortality compared to both Olyset®Plus and Royal Sentry®2.0, indicating that Vector Guard® is another promising pyrethroid-PBO ITN for controlling resistant malaria vectors.

    Keywords: Insecticide treated net, Vector Guard®, pyrethroids, Resistance, Piperonyl Butoxide, Experimental huts, Anopheles arabiensis, Tanzania

    Received: 07 Oct 2024; Accepted: 28 Nov 2024.

    Copyright: © 2024 Machange, Mbuba, Irish, Swai, Ntabaliba, Makungwa, Ngonyani, Mpelepele, Odufuwa, Kibondo and Moore. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

    * Correspondence:
    Jane Johnson Machange, Ifakara Health Institute, Ifakara, Tanzania
    Emmanuel Mbuba, Ifakara Health Institute, Ifakara, Tanzania

    Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.