Evaluation of antibody response to Plasmodium falciparum in children according to exposure of Anopheles gambiae s.l or Anopheles funestus vectors

<p>Abstract</p> <p>Background</p> <p>In sub-Saharan areas, malaria transmission was mainly ensured by <it>Anopheles. gambiae </it>s.l. and <it>Anopheles. funestus </it>vectors. The immune response status to <it>Plasmodium falciparum </it>was evaluated in children living in two villages where malaria transmission was ensured by dissimilar species of <it>Anopheles </it>vectors (<it>An. funestus vs An. gambiae </it>s.l.).</p> <p>Methods</p> <p>A multi-disciplinary study was performed in villages located in Northern Senegal. Two villages were selected: Mboula village where transmission is strictly ensured by <it>An. gambiae </it>s.l. and Gankette Balla village which is exposed to several <it>Anopheles </it>species but where <it>An. funestus </it>is the only infected vector found. In each village, a cohort of 150 children aged from one to nine years was followed during one year and IgG response directed to schizont extract was determined by ELISA.</p> <p>Results</p> <p>Similar results of specific IgG responses according to age and <it>P. falciparum </it>infection were observed in both villages. Specific IgG response increased progressively from one-year to 5-year old children and then stayed high in children from five to nine years old. The children with <it>P. falciparum </it>infection had higher specific antibody responses compared to negative infection children, suggesting a strong relationship between production of specific antibodies and malaria transmission, rather than protective immunity. In contrast, higher variation of antibody levels according to malaria transmission periods were found in Mboula compared to Gankette Balla. In Mboula, the peak of malaria transmission was followed by a considerable increase in antibody levels, whereas low and constant anti-malaria IgG response was observed throughout the year in Gankette Balla.</p> <p>Conclusion</p> <p>This study shows that the development of anti-malaria antibody response was profoundly different according to areas where malaria exposure is dependent with different <it>Anopheles </it>species. These results are discussed according to i) the use of immunological tool for the evaluation of malaria transmission and ii) the influence of <it>Anopheles </it>vectors species on the regulation of antibody responses to <it>P. falciparum</it>.</p

Evaluation of antibody response to in children according to exposure of or vectors-4

<p><b>Copyright information:</b></p><p>Taken from "Evaluation of antibody response to in children according to exposure of or vectors"</p><p>http://www.malariajournal.com/content/6/1/117</p><p>Malaria Journal 2007;6():117-117.</p><p>Published online 1 Sep 2007</p><p>PMCID:PMC2008208.</p><p></p>hildren presents for all passages (n = 62/passage in Mboula and 89/passage in Gankette Balla). Figure 1C showed median values of antibody levels (expressed in median values) in children from Mboula and Gankette Balla. NS = No Significant

Evaluation of antibody response to in children according to exposure of or vectors-3

<p><b>Copyright information:</b></p><p>Taken from "Evaluation of antibody response to in children according to exposure of or vectors"</p><p>http://www.malariajournal.com/content/6/1/117</p><p>Malaria Journal 2007;6():117-117.</p><p>Published online 1 Sep 2007</p><p>PMCID:PMC2008208.</p><p></p>t (BHN) and IgG levels (ΔDO)

Evaluation of antibody response to in children according to exposure of or vectors-1

<p><b>Copyright information:</b></p><p>Taken from "Evaluation of antibody response to in children according to exposure of or vectors"</p><p>http://www.malariajournal.com/content/6/1/117</p><p>Malaria Journal 2007;6():117-117.</p><p>Published online 1 Sep 2007</p><p>PMCID:PMC2008208.</p><p></p>d 75percentiles, and whiskers for 10and 90percentiles. The upper whisker extends to the largest value below the 75th percentile plus the box height multiplied by 1.5. n = number of children with or without malaria positive infection

Evaluation of antibody response to in children according to exposure of or vectors-2

<p><b>Copyright information:</b></p><p>Taken from "Evaluation of antibody response to in children according to exposure of or vectors"</p><p>http://www.malariajournal.com/content/6/1/117</p><p>Malaria Journal 2007;6():117-117.</p><p>Published online 1 Sep 2007</p><p>PMCID:PMC2008208.</p><p></p>and 75percentiles, and whiskers for 10and 90percentiles. The upper or lower whisker extends to the largest value below the 75percentiles plus the box height multiplied by 1.5

Evaluation of antibody response to in children according to exposure of or vectors-0

<p><b>Copyright information:</b></p><p>Taken from "Evaluation of antibody response to in children according to exposure of or vectors"</p><p>http://www.malariajournal.com/content/6/1/117</p><p>Malaria Journal 2007;6():117-117.</p><p>Published online 1 Sep 2007</p><p>PMCID:PMC2008208.</p><p></p>hildren presents for all passages (n = 62/passage in Mboula and 89/passage in Gankette Balla). Figure 1C showed median values of antibody levels (expressed in median values) in children from Mboula and Gankette Balla. NS = No Significant