Risk factors for Plasmodium falciparum and Plasmodium vivax gametocyte carriage in Papua New Guinean children with uncomplicated malaria

Risk factors for Plasmodium falciparum or Plasmodium vivax gametocyte carriage other than (as shown) treatment are explored in this study involving young Papua New Guinean children. [Display omitted] •Gametocytaemia risk factors were assessed pre- and post-treatment in young children.•Pre-treatment P. falciparum gametocytaemia reflected prior infections/immunity.•Post-treatment P. falciparum gametocytaemia was more common with anaemia.•Pre-and post-treatment P. vivax gametocytaemia paralleled the asexual parasitaemia.•These differences reflect bone marrow maturation vs rapid development in the blood. There are limited data on gametocytaemia risk factors before/after treatment with artemisinin combination therapy in children from areas with transmission of multiple Plasmodium species. We utilised data from a randomised trial comparing artemether-lumefantrine (AL) and artemisinin-naphthoquine (AN) in 230 Papua New Guinean children aged 0.5–5 years with uncomplicated malaria in whom determinants of gametocytaemia by light microscopy were assessed at baseline using logistic regression and during follow-up using multilevel mixed effects modelling. Seventy-four (32%) and 18 (8%) children presented with P. falciparum and P. vivax gametocytaemia, respectively. Baseline P. falciparum gametocytaemia was associated with Hackett spleen grade 1 (odds ratio (95% CI) 4.01 (1.60–10.05) vs grade 0; P