Fever-negative malaria parasitaemia and anaemia among children in Burkina Faso: a cross-sectional analysis linking microscopy andcaregiver reports in the 2021 Demographic and Health Survey

Background: Symptom-triggered care may not identify all children with malaria parasitaemia. We estimated the share of microscopy-positive children without caregiver-reported recent fever and described their anaemia burden in Burkina Faso. Methods: We linked the 2021 Burkina Faso Demographic and Health Survey child and household-member recodes by cluster, household and child line number. Eligible children were living, aged 6--59 months, usual residents present at interview, and had both microscopy and caregiver fever data. Ambiguous child identifiers were excluded. We estimated survey-weighted percentages and 95\% percentile confidence intervals from 399 primary-sampling-unit bootstrap replicates sampled within strata. Anaemia was classified using the DHS haemoglobin-based category. Associations are descriptive. Results: Among 5,063 linked children, 637 were microscopy positive and 426 of these had no reported fever in the preceding two weeks. Weighted microscopy positivity was 13.4\% (95\% CI 12.2--14.9). Among microscopy-positive children, 66.1\% (61.8--71.0) had no recent fever reported. Positivity was 11.9\% (10.6--13.5) among those without fever and 17.8\% (15.1--20.5) among those with fever. In the fever-negative group with available anaemia results, anaemia affected 78.2\% (74.0--83.0) of microscopy-positive children and 68.2\% (66.1--70.2) of microscopy-negative children: an unadjusted difference of 9.9 percentage points (5.0--14.8). Conclusions: Reliance on reported recent fever alone would fail to flag many children with microscopy-detectable parasitaemia in this household survey. No reported fever does not establish an asymptomatic infection; temporal mismatch, recent treatment, other symptoms and confounding limit interpretation. Targeted investigation of parasitaemia and anaemia is warranted, without inferring that universal community screening improves outcomes.