Abstract:
Background: Prescribing antimalarial medicines based on parasite confirmed diagnosis of malaria
is critical to rational drug use and optimal outcome of febrile illness. The impact of microscopybased
versus clinical-based diagnosis of childhood malaria was assessed at primary health care
(PHC) facilities using a cluster randomized controlled training intervention trial.
Methods: Sixteen PHC facilities in rural Tanzania were randomly allocated to training of health
staff in clinical algorithm plus microscopy (Arm-I, n = 5) or clinical algorithm only (Arm-II, n = 5)
or no training (Arm-III, n = 6). Febrile under-five children presenting at these facilities were
assessed, treated and scheduled for follow up visit after 7 days. Blood smears on day 0 were only
done in Arm-I but on Day 7 in all arms. Primary outcome was antimalarial drug prescription. Other
outcomes included antibiotic prescription and health outcome. Multilevel regression models were
applied with PHC as level of clustering to compare outcomes in the three study arms.
Results: A total of 973, 1,058 and 1,100 children were enrolled in arms I, II and III, respectively,
during the study period. Antimalarial prescriptions were significantly reduced in Arm-I (61.3%)
compared to Arms-II (95.3%) and III (99.5%) (both P < 0.001), whereas antibiotic prescriptions did
not vary significantly between the arms (49.9%, 54.8% and 34.2%, respectively). In Arm-I, 99.1% of
children with positive blood smear readings received antimalarial prescriptions and so did 11.3% of
children with negative readings. Those with positive readings were less likely to be prescribed
antibiotics than those with negative (relative risk = 0.66, 95% confidence interval: 0.55, 0.72). On
day 7 follow-up, more children reported symptoms in Arm-I compared to Arm-III, but fewer
children had malaria parasitaemia (p = 0.049). The overall sensitivity of microscopy reading at PHCcompared to reference level was 74.5% and the specificity was 59.0% but both varied widely
between PHCs.
Conclusion: Microscopy based diagnosis of malaria at PHC facilities reduces prescription of
antimalarial drugs, and appears to improve appropriate management of non-malaria fevers, but
major variation in accuracy of the microscopy readings was found. Lack of qualified laboratory
technicians at PHC facilities and the relatively short training period may have contributed to the
shortcomings.
Trial registration: This study is registered at Clinicaltrials.gov with the identifier NCT00687895
