Co-infection with malaria and a virus closely related to the Epstein-Barr virus (EBV) may make the malaria lethal, according to preclinical research published in PLOS Pathogens.
Children in sub-Saharan Africa become infected with EBV in infancy.
Within the same time period, they become susceptible to malaria parasite infection because protective antibodies from their mothers fade away.
“Where we think kids get into trouble is when both infections are happening at the same time, because case reports show EBV can produce a weeks-long suppression of the immune system,” said Tracey Lamb, PhD, of Emory University School of Medicine in Atlanta, Georgia.
Dr Lamb and her colleagues studied mice infected by the malaria parasite Plasmodium yoelii, which is usually non-lethal because the mice develop antibodies that control the parasites.
The researchers found that co-infection with murine gammaherpesvirus 68 (MHV68), a close relative of EBV that infects mice, made P yoelii lethal.
However, mice that had entered the chronic phase of MHV68 infection (several weeks to months after primary infection) were not affected.
The experiments indicated that MHV68 infection hinders the immune system in developing antibodies against P yoelii.
“These results are part of a pattern of evidence suggesting that clinicians treating severe malaria should check for acute EBV co-infection, and that ongoing malaria studies should include EBV as a potential risk factor for more severe forms of the disease,” said Caline Matar, a graduate student at Emory University School of Medicine.
“This phenomenon may not be unique to EBV,” added Sam Speck, PhD, also of Emory University School of Medicine.
“[I]nfections with other pathogens may also exacerbate malarial disease, since many pathogens have the capacity to suppress various components of the host immune response.”
