Monitoring of Markers of Sulfadoxine-pyrimethamine (SP) Resistance in the Implementation Countries of TIPTOP Project

The TIPTOP (Transforming Intermittent Preventive Treatment for Optimal Pregnancy) project will explore an alternative innovative approach to antenatal care (ANC) facilities or clinic for the delivery of IPTp-SP. It will sustain and scale up a community-based delivery system to be implemented in addition to the traditional ANC clinic-based delivery system with the aim of expanding coverage of IPTp-SP. The innovative approach, called community IPTp (C-IPTp-SP), will be implemented in four sub-Saharan African countries: Nigeria, Democratic Republic of Congo (DRC), Madagascar and Mozambique. TIPTOP will use community health workers (CHWs) as a delivery channel to increase coverage of IPTp-SP to a minimum of 50% in project areas to prevent malaria in pregnancy (MiP). It is expected that this will lead to a substantial increase in the consumption of SP, not supervised by professional health workers. To address the concern that this may lead to an increase in the accumulation of mutations in dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) that could lead to an increase of the parasite resistance to SP, TIPTOP will monitor the prevalence of molecular markers of SP resistance in the population at three times during the project: at baseline, midline - following approximately 18 months of implementation - and endline - after 3 years of implementation. Providing evidence on the effects on SP resistance of C-IPTp is important for decision-making as to whether C-IPTp can be recommended as an additional channel for IPTp delivery or if the use of an alternative drug for IPTp should be considered. Moreover, it is expected that the SP resistance monitoring will also help to mitigate the risk of perceiving SP as a failed drug negatively affecting demand for quality-assured (QA) SP for IPTp (risk management). C-IPTp will be implemented in each country initially in a "test" area (Phase I) and later expanded to two additional areas (Table 1). All areas have been selected purposefully. Trends of SP resistance will be monitored in the initial "test" area, with C-IPTp, and in a neighbouring area with similar epidemiologic characteristics but with no C-IPTp (control area). A health facility-based, cross-sectional survey will be conducted before project implementation (baseline), after 18 months of intervention (midline) and after three years of intervention (endline) to measure the prevalence of molecular markers associated with resistance to SP in symptomatic children under five years of age with a positive RDT attending selected health facilities in the intervention and control areas. Monitoring the prevalence of alleles associated with resistance to drugs is, by standard protocol, done by collecting samples from symptomatic children with evidence of infection. The rationale for this is that any over- or misuse of drug in any sub-population, including pregnant women, may select parasites strains resistant to SP and that those strains are then transferred by mosquitos to the general population and most easily detected in children.

During the surveys, blood samples will be collected onto filter papers (dried blood spots). The surveys will be undertaken in the intervention area (the initial area of implementation of C-IPTp) and one control area (with no C-IPTp) in each country (Figure 1). C-IPTp-SP delivery in the area of initial implementation will start immediately after baseline surveys and sample collection. The sample collection will be performed in four selected first level of care health facilities in the intervention area and four health facilities in the control area.