Online Program

Rise of vector resistance and insecticide costs: An assessment of insecticide change for indoor residual spraying (IRS) and malaria burden in Zimbabwe

Tuesday, November 3, 2015 : 5:30 p.m. - 5:45 p.m.

Beth Brennan, MPH, Abt Associates, Inc., Bethesda, MD
Benjamin Johns, PhD, International Health Division, Abt Associates Inc., Bethesda, MD
Elana Fiekowsky, MALD, International Health Division, Abt Associates, Bethesda, MD
Indoor residual spraying (IRS) has been implemented since the 1940s in Zimbabwe and has protected millions of people from malaria across the country. However, entomological studies have shown increasing resistance to pyrethroid-based insecticides in mosquitos, but the population-level effects of changing insecticides is not well understood.

In November 2014, the President’s Malaria Initiative-supported (PMI) Africa Indoor Residual Spraying (AIRS) project implemented spraying in four districts in Manicaland province with an organophosphate-based insecticide. The study is intended to assess if using organophosphates (OPs) in IRS has an effect on the number of confirmed malaria cases at health facilities compared to using pyrethroids (PYs) in other IRS districts. Organophosphates (OPs) are substantially more costly, roughly ten times more expensive per area sprayed, than PYs. Thus, as programs expand and require more expensive insecticide, the number of beneficiaries an IRS campaign can protect is dependent on the type of insecticide used.

With Health Management Information System (HMIS) data through malaria transmission season (May 2015), we will: 1) compare the number of confirmed malaria cases in health facilities in four districts in 2011-2014 (under PYs) to the same districts in 2014 (under OPs); and (2) compare the number of confirmed malaria cases in health facilities in the four OP districts in 2014 to four comparison PY districts in the same time period. Although not randomized-controlled, the analysis provides a relatively inexpensive method to suggest the most effective pesticide for reducing malaria burden in these districts, while considering increasing insecticide costs and budgets limitations.

Learning Areas:


Learning Objectives:
Assess population-level effects of organophosphate insecticide use for IRS compared to the long-term use of pyrethroid insecticides. Describe how Zimbabwe’s publicly-available HMIS/DHIS2 data facilitate the investigation of IRS effect on malaria burden at health clinics. Demonstrate how HMIS/DHIS2 data can be used to make evidence-based IRS programming decisions.

Keyword(s): International Health, Evidence-Based Practice

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: Elana Fiekowsky is the Gender Advisor and an M&E Specialist for the PMI Africa Indoor Residual Spray (AIRS) Project. On the PMI AIRS Project, Ms. Fiekowsky is responsible for managing the M&E activities in Benin, Madagascar, Mozambique, and Rwanda for the PMI AIRS project. Ms. Fiekowsky works closely with the donor, PMI, to ensure that the project delivers project monitoring data and evaluations of project implementation.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.