Cytomegalovirus (CMV) is considered as a significant driver of immune variations that fundamentally alters immune cell composition and function. The association between CMV and other pathogens vaccine have shown reduced responses for example SARS Co-V2, influenza. However, to date the impact of CMV on malaria has not been investigated although this virus is highly prevalent in malaria endemic region. Therefore, here we investigated the impact of CMV on innate and adaptive immune responses to malaria. To do this, we measured innate transcriptional responses in healthy malaria naïve CMV positive and negative individuals after in vitro stimulation of peripheral blood mononuclear cells with Plasmodium falciparum. We further analysed adaptive responses measuring antibody responses and CD4+T cells phenotype in malaria naïve individuals who were intravenously infected with Plasmodium-infected RBCs.
We found a higher parasite multiplication rate in CMV positive individuals with altered innate immune transcriptional profiles. In addition, CMV positive participants had higher induction of Th1-follicular helper cells and reduced malaria specific antibodies. Therefore, CMV infection has shown negative impact on acquisition of protective immunity to malaria and reduced parasite control suggesting an impact on both innate and adaptive responses.