Helminth-infected Mozambican children with malaria have increased anaemia, cytokines and helminth-specific antibodies.

Owing to their overlapping geographical distribution and the consequent occurrence of coinfections, several studies have evaluated the impact of helminth infections on malaria immune responses and clinical outcomes. However, little has been reported on how malaria coinfection affects anthelmintic responses in children harbouring worm infections. We therefore aimed to assess the impact of malaria coinfection on helminth-related clinical and immune outcomes in children. Here, we measured in plasma the levels of 30 cytokines, total IgE, and helminth-specific IgM, IgA, IgG, IgG1-4, and IgE antibodies to a panel of 11 helminth antigens by Luminex. Samples were obtained from 441 children aged 2-10 years with diverse symptomatology, recruited from two hospitals in the Manhiça District (Mozambique). Parasite infections were diagnosed by rapid antigen diagnostic test, microscopy, and/or quantitative PCR. Among the recruited children, 96 were diagnosed with helminth infection, of whom 16 (17%) were coinfected with Plasmodium falciparum, and 80 (83%) had helminth infection alone. Coinfection was associated with an increased prevalence of anaemia (33% [5/15], p = 0.006) compared to helminth infection alone. Coinfected children also exhibited higher concentrations of pro-inflammatory cytokines (IL-2R and IL-6), cell-recruiting chemokines (MCP-1 and MIG), anti-inflammatory proteins (IL-1RA and IL-10), and the growth factor HGF (p < 0.05). Additionally, helminth-specific antibody responses were significantly enhanced (p < 0.05) in coinfected participants, with total IgG and IgM responses showing the strongest associations with coinfection. Notably, antibodies to several antigens, including Sh-SERPIN, Sm-SERPIN, As-37, Na-SAA-2, Na-GST-1, and Tm-16, were consistently increased across multiple isotypes (IgG, IgG cytophilic subclasses, IgM, and IgE) among coinfected children. In summary, malaria coinfection was associated with an increased risk of anaemia and enhanced inflammation and specific antibody responses in helminth-infected children, which could potentially influence worm expulsion or survival, as well as helminth vaccine efficacy.