Quantifying the Epidemiological Impact of Targeted Indoor Residual Spraying on Aedes-borne Diseases

Emory University

Status: Completed

Conditions: Dengue; Zika; Chikungunya; Aedes-borne Diseases

Treatments: Other: Targeted Indoor Residual Spraying (TIRS)

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT04343521

IRB00108666

1U01AI148069-01 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The objective of this trial is evaluate the efficacy of Targeted Indoor Residual Spraying (TIRS) in preventing symptomatic disease caused by Aedes-borne diseases (ABDs) in children 2 to 15 years of age in the city of Merida, Yucatan State, Mexico.

Full description

Contemporaneous urban vector control (truck-mounted ultra-low volume spraying, thermal fogging, larviciding) has failed to contain dengue epidemics and to prevent the global range expansion of Aedes-borne diseases (ABDs: dengue, chikungunya, zika). Part of the challenge in sustaining effective ABD control emerges from the remarkable paucity of evidence about the epidemiological impact of any vector control method. Furthermore, the classic deployment of interventions in response to clinical cases fails to account for the important contribution of out-of-home human mobility and asymptomatic infections.

The trial will be conducted in the city of Merida extending ongoing longitudinal cohort to follow a population of 4,600 children 2-15 years old randomly allocated to receive either TIRS treatment or not. If efficacious, TIRS will drive a paradigm shift in Aedes control by: considering Ae. aegypti behavior to rationally guide insecticide applications; the change to preventive control (pre- ABD transmission season rather than in response to symptomatic cases); the use of third generation insecticides to which Ae. Aegypti is susceptible.

Enrollment: 4,461 patients

Sex: All

Ages: 2 to 15 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Household Level Inclusion Criteria:

• Household is located within the bounds of a study cluster (5x5 city-block clusters)
• City block has at least 60% premises that are residential

Individual Level Inclusion Criteria:

• 2 or more and up to 15 years of age at the time of initial enrollment
• Living in a house that consented to TIRS (for children in TIRS cluster)

Exclusion criteria

Household Level Exclusion Criteria:

• Households where study personnel identify a security risk (i.e., site where drugs are sold, residents are always drunk or hostile)
• Sites where no residents spend time during the day (i.e. work 7days a week outside the home)
• Inability for a resident to provide informed consent
• Non-residential places (e.g., businesses, schools, markets, etc.)

Individual Level Exclusion Criteria:

• Less than 2 years of age or more than 15 years of age at the time of enrollment
• Not living in a house that consented to TIRS (for children in TIRS cluster)
• Having a medical condition that prevents implementation of study procedures
• Temporary visitor to household
• Plans to leave study area within next 12 months

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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4,461 participants in 2 patient groups

Targeted Indoor Residual Spraying (TIRS)

Experimental group

Description:

All households in Targeted Indoor Residual Spraying (TIRS) clusters will be offered the intervention, and children in households that consent to TIRS will be recruited into this study arm.

Treatment:

Other: Targeted Indoor Residual Spraying (TIRS)

Routine Aedes-borne Virus (ABV) Prevention and Control

No Intervention group

Description:

Households in the control clusters receive routine Aedes-borne virus (ABV) prevention and control, without Targeted Indoor Residual Spraying (TIRS). Children in the control households will be recruited into this study arm.