Malaria Journal (Dec 2007)

Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)

  • Schreiber Nadine,
  • Tosun Meral,
  • Busch Wibke,
  • Marks Florian,
  • Thompson Peter A,
  • Thompson Benedicta,
  • Kreuels Benno,
  • Kreuzberg Christina,
  • Adjei Samuel,
  • Kobbe Robin,
  • Opoku Ernest,
  • Adjei Ohene,
  • Meyer Christian G,
  • May Juergen

DOI
https://doi.org/10.1186/1475-2875-6-163
Journal volume & issue
Vol. 6, no. 1
p. 163

Abstract

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Abstract Background Intermittent preventive antimalarial treatment in infants (IPTi) is currently evaluated as a malaria control strategy. Among the factors influencing the extent of protection that is provided by IPTi are the transmission intensity, seasonality, drug resistance patterns, and the schedule of IPTi administrations. The aim of this study was to determine how far the protective efficacy of IPTi depends on spatio-temporal variations of the prevailing incidence of malaria. Methods One thousand seventy infants were enrolled in a registered controlled trial on the efficacy of IPTi with sulphadoxine-pyrimethamine (SP) in the Ashanti Region, Ghana, West Africa (ClinicalTrial.gov: NCT00206739). Stratification for the village of residence and the month of birth of study participants demonstrated that the malaria incidence was dependent on spatial (range of incidence rates in different villages 0.6–2.0 episodes/year) and temporal (range of incidence rates in children of different birth months 0.8–1.2 episodes/year) factors. The range of spatio-temporal variation allowed ecological analyses of the correlation between malaria incidence rates, anti-Plasmodium falciparum lysate IgG antibody levels and protective efficacies provided by IPTi. Results Protective efficacy of the first SP administration was positively correlated with malaria incidences in children living in a distinct village or born in a distinct month (R2 0.48, p 2 0.63, p Conclusion The spatial and temporal variations of malaria incidences in a geographically and meteorologically homogeneous study area exemplify the need for close monitoring of local incidence rates in all types of intervention studies. The increase of the protective efficacy of IPTi with malaria incidences may be relevant for IPTi implementation strategies and, possibly, for other malaria control measures.