Mixed infection decreases malaria burden and escalate relapsing fever
(English)Manuscript (Other academic)
About 500 million cases of malaria occur annually. However, a substantial number of patients who actually have relapsing fever (RF) Borrelia are misdiagnosed with malaria due to similar manifestation and geographic distribution of the two diseases. More alarmingly, high prevalence of mixed infections with malaria and RF Borrelia has been reported. Therefore, we developed a mouse model to study the effects of such mixed infection. We observed a 21-fold increase in spirochete titers, whereas parasitemia decreased 15-fold. This may be explained by polarization of the host immune response towards the intracellular malaria parasite, resulting in unaffected extracellular spirochetes and hosts succumb to sepsis. Furthermore, secondary malaria infection can reactivate a quiescent RF brain infection, which is the first evidence of a clinically and biologically relevant cue for reactivation of dormant RF Borrelia infection. Mixed infection also resulted in severe anemia even though the parasite counts were low. Our study highlights the importance of investigating mixed infections in vivo to elucidate the immune responses that are involved in the clinical outcome, and it also emphasizes the urgent need for improved diagnostics of malaria and other infectious diseases such as RF Borrelia.
Malaria, Plasmodium, Relapsing fever Borrelia, and mixed infections
Cell and Molecular Biology
Research subject Infectious Diseases
IdentifiersURN: urn:nbn:se:umu:diva-21815OAI: oai:DiVA.org:umu-21815DiVA: diva2:211913