Beyond Gametocyte Density: Sex-Structured Reproductive Availability Improves Prediction of Plasmodium falciparum Mosquito Infection

Aggregate gametocyte abundance may discard information about the male and female sexual-stage composition required for Plasmodium falciparum transmission. This preprint reports an independent secondary analysis of public source data from 148 membrane-feeding experiments comprising 7,757 dissected mosquitoes and 1,297 infections. Sex-structured female and male gametocyte availability improved prediction of mosquito infection relative to aggregate abundance across in-sample comparison, geographic holdout, nonlinear abundance baselines, density ablation, influence analysis, leave-one-feed-out prediction, and feed-level bootstrap resampling. The advantage was not universal: a cubic abundance model performed slightly better in Balonghin, and equal-feed weighting did not favor the additional sex-specific parameter by AIC. The analysis quantifies the predictive information lost when female and male gametocyte densities are collapsed into one abundance measure and motivates prospective evaluation of functional transmission biomarkers and transmission-blocking interventions. It does not establish a clinical infectiousness model or treatment effect.