title: Performance of rapid diagnostic test, blood-film microscopy and PCR for the diagnosis of malaria infection among febrile children from Korogwe District, Tanzania.
abstract: BACKGROUND
  Rapid diagnostic tests (RDT) and light microscopy are still recommended for diagnosis to guide the clinical management of malaria despite difficult challenges in rural settings. The performance of these tests may be affected by several factors, including malaria prevalence and intensity of transmission. The study evaluated the diagnostic performance of malaria RDT, light microscopy and polymerase chain reaction (PCR) in detecting malaria infections among febrile children at outpatient clinic in Korogwe District, northeastern Tanzania.
  
  
  METHODS
  The study enrolled children aged 2-59 months with fever and/or history of fever in the previous 48 h attending outpatient clinics. Blood samples were collected for identification of Plasmodium falciparum infection using histidine-rich-protein-2 (HRP-2)-based malaria RDT, light microscopy and conventional PCR.
  
  
  RESULTS
  A total of 867 febrile patients were enrolled into the study. Malaria-positive samples were 85/867 (9.8 %, 95 % CI, 7.9-12.0 %) by RDT, 72/867 (8.3 %, 95 % CI, 6.5-10.1 %) by microscopy and 79/677 (11.7 %, 95 % CI, 9.3-14.3 %) by PCR. The performance of malaria RDT compared with microscopy results had sensitivity and positive predictive value (PPV) of 88.9 % (95 % CI, 79.3-95.1 %) and 75.3 % (95 % CI, 64.8-84.0 %), respectively. Confirmation of P. falciparum infection with PCR analysis provided lower sensitivity and PPV of 88.6 % (95 % CI, 79.5-94.7 %) and 84.3 % (95 % CI, 74.7-91.4 %) for RDT compared to microscopy.
  
  
  CONCLUSIONS
  Diagnosis of malaria infection is still a challenge due to variation in results among diagnostic methods. HRP-2 malaria RDT and microscopy were less sensitive than PCR. Diagnostic tools with high sensitivity are required in areas of low malaria transmission.
authors.affiliation: Korogwe Research Station, Tanga Centre, National Institute for Medical Research, P. O. Box 5004, Tanga, Tanzania. cbdmahende@yahoo.co.uk.|Department of Medical Entomology and Parasitology, School of Public Health, Muhimbili University of Health and Allied Sciences, P. O. Box 65001, Dar es Salaam, Tanzania. cbdmahende@yahoo.co.uk.
authors.forename: Coline
authors.initials: C
authors.lastname: Mahende
authors.affiliation: Department of Medical Entomology and Parasitology, School of Public Health, Muhimbili University of Health and Allied Sciences, P. O. Box 65001, Dar es Salaam, Tanzania.
authors.forename: Billy
authors.initials: B
authors.lastname: Ngasala
authors.affiliation: Korogwe Research Station, Tanga Centre, National Institute for Medical Research, P. O. Box 5004, Tanga, Tanzania.|Department of International Health, Microbiology and Immunology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: John
authors.initials: J
authors.lastname: Lusingu
authors.affiliation: Department of Environmental Medical Biology, Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
authors.forename: Tai-Soon
authors.initials: TS
authors.lastname: Yong
authors.affiliation: Korogwe Research Station, Tanga Centre, National Institute for Medical Research, P. O. Box 5004, Tanga, Tanzania.
authors.forename: Paminus
authors.initials: P
authors.lastname: Lushino
authors.affiliation: Korogwe Research Station, Tanga Centre, National Institute for Medical Research, P. O. Box 5004, Tanga, Tanzania.
authors.forename: Martha
authors.initials: M
authors.lastname: Lemnge
authors.affiliation: Korogwe Research Station, Tanga Centre, National Institute for Medical Research, P. O. Box 5004, Tanga, Tanzania.
authors.forename: Bruno
authors.initials: B
authors.lastname: Mmbando
authors.affiliation: Department of Medical Entomology and Parasitology, School of Public Health, Muhimbili University of Health and Allied Sciences, P. O. Box 65001, Dar es Salaam, Tanzania.
authors.forename: Zul
authors.initials: Z
authors.lastname: Premji
mesh_terms: D001769:Blood / Q000469:parasitology*; D002675:Child, Preschool; D002846:Chromatography, Affinity / Q000379:methods*; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D005334:Fever / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D008288:Malaria / Q000175:diagnosis* / Q000469:parasitology; D008297:Male; D008853:Microscopy / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013636:Tanzania
keywords: Children; Febrile; Korogwe; Malaria; Malaria rapid diagnostic test; Microscopy; Outpatient; Plasmodium falciparum; Polymerase chain reaction (PCR); Tanzania