Research Article
Reduced Parasite Burden in Children with
Falciparum Malaria and Bacteremia Coinfections:
Role of Mediators of Inflammation
Gregory C. Davenport,
1,2
James B. Hittner,
3
Vincent Otieno,
4
Zachary Karim,
2
Harshini Mukundan,
5
Paul W. Fenimore,
6
Nicolas W. Hengartner,
6
Benjamin H. McMahon,
6
Prakasha Kempaiah,
2
John M. Ong’echa,
4
and Douglas J. Perkins
2,4
1
Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
2
Center for Global Health, Department of Internal Medicine, Division of Infectious Diseases, School of Medicine,
University of New Mexico, Albuquerque, NM 87131, USA
3
Department of Psychology, College of Charleston, Charleston, SC, USA
4
University of New Mexico/KEMRI Laboratories of Parasitic and Viral Diseases, Centre for Global Health Research,
Kenya Medical Research Institute, Kisumu, Kenya
5
Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM, USA
6
Teoretical Biology Group, Teoretical Division, Los Alamos National Laboratory, Los Alamos, NM, USA
Correspondence should be addressed to Douglas J. Perkins; dperkins@salud.unm.edu
Received 29 January 2016; Accepted 28 April 2016
Academic Editor: Denis Girard
Copyright © 2016 Gregory C. Davenport et al. Tis is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Bacteremia and malaria coinfection is a common and life-threatening condition in children residing in sub-Saharan Africa. We
previously showed that coinfection with Gram negative (G[−]) enteric Bacilli and Plasmodium falciparum (Pf [+]) was associated
with reduced high-density parasitemia (HDP, >10,000 parasites/L), enhanced respiratory distress, and severe anemia. Since
infammatory mediators are largely unexplored in such coinfections, circulating cytokines were determined in four groups of
children ( = 206, aged <3 yrs): healthy; Pf [+] alone; G[−] coinfected; and G[+] coinfected. Staphylococcus aureus and non-Typhi
Salmonella were the most frequently isolated G[+] and G[−] organisms, respectively. Coinfected children, particularly those with
G[−] pathogens, had lower parasite burden (peripheral and geometric mean parasitemia and HDP). In addition, both coinfected
groups had increased IL-4, IL-5, IL-7, IL-12, IL-15, IL-17, IFN-, and IFN- and decreased TNF- relative to malaria alone. Children
with G[−] coinfection had higher IL-1 and IL-1Ra and lower IL-10 than the Pf [+] group and higher IFN- than the G[+] group.
To determine how the immune response to malaria regulates parasitemia, cytokine production was investigated with a multiple
mediation model. Cytokines with the greatest mediational impact on parasitemia were IL-4, IL-10, IL-12, and IFN-. Results here
suggest that enhanced immune activation, especially in G[−] coinfected children, acts to reduce malaria parasite burden.
Dedicated to our beloved friend and colleague Gregory C. Davenport, Ph.D., PCPH, MLT (ASCP), who passed away
unexpectedly on Wednesday, 21 August of 2013, at 41 years of age
1. Introduction
Kenya is one of WHO African-region countries that bears the
greatest global yearly burden of malaria, afecting primarily
children less than fve years of age and pregnant women [1].
Western Kenya is a holoendemic area of Plasmodium falci-
parum transmission which leads to early and chronic expo-
sure of children to the malaria parasite and, consequently,
Hindawi Publishing Corporation
Mediators of Inflammation
Volume 2016, Article ID 4286576, 14 pages
http://dx.doi.org/10.1155/2016/4286576