The COVID-19 pandemic led to concerns of exacerbating the severity of endemic malarial infections via a syndemic. Accordingly, this systematic review investigated the disease severity of COVID-19 and malarial co-infection (CMCI) patients to assess potential clinical implications.
PubMed and NCBI were searched using relevant MeSH terms. 34 records were identified and screened, yielding 29 eligible papers. 14 case reports were stratified by age, sex, causative agent and obstetric status. Assessment of biochemical abnormalities found lymphocytopenia in 25% of all coinfection cases and 40% of non-pregnant adult cases. Thrombocytopenia was found to be the most common finding in CMCIs; particularly elevated in nonpregnant adults (90%) and Plasmodia falciparum (Pf) coinfections (100%). Despite hypotheses suggesting increased severity of CMCI in paediatric patients, our case analysis found that the majority of children were asymptomatic with fewer biomarker abnormalities. Falciparum-induced Th1-priming in Pf-positive patients was theorised to contribute to increased viral clearance; however, COVID-19’s ability to reactivate dormant non-falciparum malaria remains a concern.
CMCI clinical outcomes are heterogenous and context dependent. Clinical severity is determined by a multitude of factors including age, sex, causative agent and obstetric status. Further research is necessary to determine the public health risks, salient for tackling future pandemics.