Abstract
Malaria is widely reported to suppress immune responses to heterologous antigens, including vaccines, but the evidence base for this assumption is patchy and confusing. Here we review the evidence for malaria-mediated suppression of responses to vaccination and conclude that: there is evidence of impairment of responses to heterologous polysaccharide antigens in children with clinical malaria or asymptomatic parasitemia; there is little evidence of impairment of responses to routine, protein-based childhood vaccine regimens; and the underlying mechanisms of impaired responsiveness, and especially of impaired responses to T-independent polysaccharide antigens, remain unclear. We suggest that, with the possible exception of vaccines against encapsulated bacteria, the benefits of postponing vaccination until a malaria infection has cleared are probably outweighed by the risk of missing opportunities to vaccinate hard-to-reach populations.
Acknowledgements
The authors would like to thank Brian Greenwood for his helpful comments on the initial manuscript.
Financial & competing interests disclosure
Aubrey J Cunnington holds a Medical Research Council clinical research training fellowship (G0701427). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.