Serological assessment of pediatric parasite exposure in two Senegalese districts using multiplex serology

Although pediatric parasitic diseases cause significant morbidity and mortality in regions with high rates of co-infection, this overlap may offer opportunities for integrated control strategies. This study aimed at a serological assessment of exposure to multiple parasitic infections among children aged 1-14 years in two Senegalese districts, Saraya (Kédougou Region) and Diourbel (Diourbel Region), to inform integrated control strategies. We analysed 883 dried blood spot samples. A multiplex bead-based immunoassay quantified IgG antibody against <i>Plasmodium falciparum</i>, helminths (<i>Necator americanus</i>, <i>Schistosoma mansoni</i>, <i>Strongyloides stercoralis</i>, <i>Taenia solium</i>), and intestinal protozoa (<i>Cryptosporidium parvum</i>, <i>Giardia duodenalis</i>) as proxies for single- and multiple-pathogen exposure. Multivariable logistic regression identified risk factors for seropositivity. Recent malaria exposure was identified in 11% of children, while 42% showed evidence of historical exposure. Helminth seroprevalence ranged between 0.1% and 7.2%, whereas <i>Cryptosporidium parvum</i> and <i>Giardia duodenalis</i> seroprevalence values were 19.0% and 7.4%, respectively. Co-exposures to malaria and other parasites ranged from 9.4% to 18.0%. School-aged children exhibited higher seroprevalence rates for historical exposure to <i>P. falciparum</i> and <i>S. stercoralis</i> compared to pre-school children, while <i>G. duodenalis</i> was more seroprevalent in pre-school children. Saraya exhibited higher seroprevalence for historical <i>P. falciparum</i> and <i>G. duodenalis</i> exposure. Rare/never handwashing before meals, shorter travel time to a water source (< 10 min, likely reflecting residence near shared or surface water rather than improved household taps), and frequent contact with any waterbodies (daily/weekly) were associated with higher odds of parasite seropositivity. While seasonal malaria chemoprevention appears suitable, the low helminth seroprevalence coupled with substantial protozoan exposure suggests that current integrated interventions may require re-evaluation and enhancement.