The associations between significance terms in the multivariate analysis for P. falciparum infections were further assessed to test the significance of the product terms directly i.e., age in years [adjusted odds ratio (AOR), 3.1; 95 % confidence interval (CI) 1.1–5.6], Hb concentration (AOR = 0.71; 95 % CI 0.42–2.3), and stunted malnutrition (AOR, 8.72; 95 % CI 4.8–25.1). Here, GSTM1 is linked to malnutrition.