Trends in fever case management for febrile inpatients in a low malaria incidence setting of Tanzania

Citation: 
Deng B Madut 1 2, Matthew P Rubach 1 2, John P Bonnewell 1 2 3, Elena R Cutting 4, Manuela Carugati 1, Nathaniel Kalengo 5, Michael J Maze 6 7, Anne B Morrissey 1, Blandina T Mmbaga 5 8, Bingileki F Lwezaula 9, Grace Kinabo 5, Ronald Mbwasi 5, Kajiru G Kilonzo 5 8, Venance P Maro 5 8, John A Crump 1 2 7
Publication year: 
2021

Objectives: In 2010, WHO published guidelines emphasising parasitological confirmation of malaria before treatment. We present data on changes in fever case management in a low malaria transmission setting of northern Tanzania after 2010.

Methods: We compared diagnoses, treatments and outcomes from two hospital-based prospective cohort studies, Cohort 1 (2011-2014) and Cohort 2 (2016-2019), that enrolled febrile children and adults. All participants underwent quality-assured malaria blood smear-microscopy. Participants who were malaria smear-microscopy negative but received a diagnosis of malaria or received an antimalarial were categorised as malaria over-diagnosis and over-treatment, respectively.

Results: We analysed data from 2098 participants. The median (IQR) age was 27 (3-43) years and 1047 (50.0%) were female. Malaria was detected in 23 (2.3%) participants in Cohort 1 and 42 (3.8%) in Cohort 2 (p = 0.059). Malaria over-diagnosis occurred in 334 (35.0%) participants in Cohort 1 and 190 (17.7%) in Cohort 2 (p < 0.001). Malaria over-treatment occurred in 528 (55.1%) participants in Cohort 1 and 196 (18.3%) in Cohort 2 (p < 0.001). There were 30 (3.1%) deaths in Cohort 1 and 60 (5.4%) in Cohort 2 (p = 0.007). All deaths occurred among smear-negative participants.

Conclusion: We observed a substantial decline in malaria over-diagnosis and over-treatment among febrile inpatients in northern Tanzania between two time periods after 2010. Despite changes, some smear-negative participants were still diagnosed and treated for malaria. Our results highlight the need for continued monitoring of fever case management across different malaria epidemiological settings in sub-Saharan Africa.