Evaluation of IR3535 as a Spatial Repellent for Malaria Control.

NCT04419766 | Active Not Recruiting

• 1 other identifier: REPELMALARIA
• Study Type: interventional
• Target: 166
• Locations: 1 country
• Sites: 1

Brief Summary

Mozambique contributes with 5% of global malaria cases, and despite control efforts the Sofala province continues to experience a high burden of malaria. The resistance to insecticides and changes in vector habits can compromise the use of common vector control tools. The use of spatial repellents is thus an interesting alternative, as it does not exert selective pressure on resistance genes or eliminate other insects with impact on biodiversity. IR3535 is a non-toxic repellent and if used at community level can extend protection to outdoor biting. Hypothesis: Using the IR3535 repellent for indoor and outdoor spraying will reduce the prevalence of malaria and reduce vector density and infection. An experimental Before-After-Control-Intervention will be carried out with two groups: a) Intervention (Tambai Q2 and Q6): with intra and extra-household spraying with IR3535 and b) Control (Tambai Q3 and Q4): without spraying. Tambai is acommunity of Bebedo, Nhamatanda, Sofala, Mozambique. The mosquito distribution, diversity, density and sporozoite rate will be monitored indoors and outdoors in both communities for 2 years. The prevalence of malaria will be determined in under five years old children at the beginning, the end of the 1st year and at the end of the study. Additionally, cross-sectional studies with a mixed approach assessing the community knowledge, attitudes and practices (KAP) will be carried out to detect gaps that persist at the community level. Heads of households and health professionals will be interviewed at the beginning of the study, the end of 1st year and at the end of the study. The data will be analyzed using SPSS and R software packages. For matching situations (before and after), the McNemar test will be used to ascertain statistical significance. Generalized Linear Models (GLM) will be used to jointly analyze several explanatory variables. Linear Mixed Models (LMM) and Generalized Estimation Equation (GEE) models will be used to compare longitudinal data. The prevalence of malaria and entomological indices relevant for transmission are expected to decrease with the intervention while community knowledge on malaria and its control are expected to increase.

Conditions

Malaria

Keywords

Malaria control; Spatial Repellent; vector control; KAP

Outcome Measures

Primary Outcomes (7)

• Changes from baseline in malaria prevalence in children under 5 years at 1st year

  Malaria cases in children aged 6 to 59 months

  Month 1, Month 12

• Changes from baseline in malaria prevalence in children under 5 years at 2nd year

  Malaria cases in children aged 6 to 59 months

  Month 1, Month 24

• Monthly changes of indoor Anopheles mosquito density from baseline to month 24

  Mosquitoes resting inside the houses will be collected by aspiration

  1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 19, 20, 21, 22, 23, 24 Months

• Monthly changes of outdoor Anopheles mosquito density from baseline to month 24

  Outside mosquitoes collected overnight using CDC-light traps

  1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 19, 20, 21, 22, 23, 24 Months

• Monthly changes of Anopheles mosquito sporozoite rate

  Number of infected mosquitoes determined by PCR

  1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 19, 20, 21, 22, 23, 24 Months

• Change from Baseline in Knowledge, attitudes and practices - KAP score at 1st year

  An evaluation scale will be defined with the attribution of points for correct answers, and whoever has \<50% will be considered a participant with a bad level of knowledge, attitudes and practices and whoever has 50% -74% and ≥75% will be considered medium and high level of knowledge, attitudes or practices respectively

  Month 1, Month 12

• Change from Baseline in Knowledge, attitudes and practices - KAP score at 2nd

  An evaluation scale will be defined with the attribution of points for correct answers, and whoever has \<50% will be considered a participant with a bad level of knowledge, attitudes and practices and whoever has 50% -74% and ≥75% will be considered medium and high level of knowledge, attitudes or practices respectively

  Month 1, Month 24

Secondary Outcomes (2)

• Mosquito breeding sites mapping

  continuous for the 2 years

• Prevalence of symptomatic malaria cases in the area covered by the Vinho health center

  continuous for the 2 years

Study Arms (2)

intervention

EXPERIMENTAL

Community of Tambai: Indoors and outdoors spraying with IR3535 (3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester)

Other: IR3535 (3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester) house spraying

Control

NO INTERVENTION

Community of Micheu 1: Without spraying.

Interventions

IR3535 (3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester) house spraying OTHER

The spraying will be performed monthly during the first 3 months, bimonthly during the next 6 months and then quarterly thereafter. The spraying will be carried out inside and outside the houses during the morning.

intervention

Eligibility Criteria

• Age: 6 Months+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• aged 6 to 59 months
• resident in the communities under study
• to give informed consent for participation by parents or legal representatives
• availability on the day of the study.

You may not qualify if:

• aged below 6 months and older than 59 months
• being infected with or having undergone malaria treatment for up to one month
• lack of consent from parents or legal representatives.
• Be the head of household or someone appointed by her/him and a resident at the place of study
• Be a health professional in the area of Vinho health center
• Be available on the day of the interview
• Have consented to participate in the study
• Having a mental illness or having a change in behavior

Sponsors & Collaborators

• Universidade Nova de Lisboa: lead
• Centro de Investigação Operacional da Beira, Mozambique: collaborator
• Fundação Belmiro de Azevedo, Portugal: collaborator

Study Sites (1)

Centro de Investigação Operacional da Beira, Instituto Nacional de Saúde, Ministério de Saúde, Mozambique

Beira, Sofala, Bairro Ponta Gêa, Mozambique

Location

Related Publications (13)

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  BACKGROUND

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  PMID: 25378761 BACKGROUND

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  PMID: 17695343 BACKGROUND

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• Wampler PJ, Rediske RR, Molla AR. Using ArcMap, Google Earth, and Global Positioning Systems to select and locate random households in rural Haiti. Int J Health Geogr. 2013 Jan 18;12:3. doi: 10.1186/1476-072X-12-3.

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• Lequechane JD, Chale F, Azevedo N, Abilio AP, Muanido AG, Goncalves L, Manuel JL, Silveira H. Knowledge, attitude and practice in high endemic settings for malaria: a cross-sectional study in a rural community in central Mozambique. Malar J. 2025 Nov 28;24(1):431. doi: 10.1186/s12936-025-05652-8.

  PMID: 41316240 DERIVED

• Lequechane JD, Craveiro I, Azevedo N, Abilio AP, Zimba E, Carvalho M, Duaja A, Goncalves L, Manuel JL, Silveira H. Community participatory mapping of malaria mosquito breeding sites in Mozambique. Malar J. 2024 Aug 29;23(1):264. doi: 10.1186/s12936-024-05084-w.

  PMID: 39210393 DERIVED

MeSH Terms

Conditions

Malaria

Interventions

ethyl-3-(N-n-butyl-N-acetyl)aminopropionate

Condition Hierarchy (Ancestors)

Protozoan Infections; Parasitic Diseases; Infections; Mosquito-Borne Diseases; Vector Borne Diseases

Study Officials

• Henrique Silveira, PhD

  Universidade Nova de Lisboa, Portugal

  PRINCIPAL INVESTIGATOR

• Joaquim Lequechane, Lic

  Centro de Investigação Operacional da Beira, INS, MISAU, Mozambique

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: A prospective experimental Before-After-Control-Intervention test will be carried out with two groups: a) Intervention (community of Tambai): with indoors and outdoors spraying with IR3535 (3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester) and b) Control (community of Micheu 1): without spraying.

Study Record Dates

• First Submitted: May 12, 2020
• First Posted: June 5, 2020
• Study Start: April 28, 2021
• Primary Completion: July 1, 2025
• Study Completion: October 1, 2025
• Last Updated: March 30, 2025

Record last verified: 2024-12

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: The information will be realised at the end of the project
• Access Criteria: public

Locations

MO (1)