Performance and time to become negative after treatment of three malaria rapid diagnostic tests in low and high malaria transmission settings

Abstract

BackgroundThe performance of different malaria rapid diagnostic tests (RDT) may be influenced by transmission intensity and by the length of time each test requires to become negative after treatment and patient’s recovery.MethodsResults of three RDTs (two HRP2 and one pLDH antigen-based tests) were compared to blood smear microscopy (the gold standard method) in children under 5 years of age living in a high versus low malaria intensity setting in southwestern Uganda. In each setting, 212 children, who tested positive by at least one RDT and by microscopy, were treated with artemether-lumefantrine. RDTs and microscopy were then repeated at fixed intervals to estimate each test’s time to negativity after treatment and patient recovery.ResultsIn the two settings, sensitivities ranged from 98.4 to 99.2 % for the HRP2 tests and 94.7 to 96.1 % for the pLDH test. Specificities were 98.9 and 98.8 % for the HRP2 tests and 99.7 % for the pLDH test in the low-transmission setting and 79.7, 80.7 and 93.9 %, respectively, in the high-transmission setting. Median time to become negative was 35–42 or more days for the HRP2 tests and 2 days for the pLDH test.ConclusionsHigh transmission contexts and a long time to become negative resulted in considerably reduced specificities for the HRP2 tests. Choice of RDT for low- versus high-transmission settings should balance risks and benefits of over-treatment versus missing malaria cases. Trial registration: Registry number at ClinicalTrial.gov: NCT01325974Electronic supplementary materialThe online version of this article (doi:10.1186/s12936-016-1529-6) contains supplementary material, which is available to authorized users.

Comparative Rapid Diagnostic Test Kit and Presumptive Treatment of Fever Cases in the Hohoe Municipality, Ghana

“…This confirmed previous studies from Tanzania [9] and Ghana [1] with 63% and 73% specificities respectively. The high specificity (91.9%) in the low-transmission season was similar to another study in Uganda with 98.9% specificity using HRP2 antigen-based test [6]. In a Community with high frequency of Malaria infections together with long-lasting HRP2 antigens, quasi-persistent antigen positivity, results in children living in Communities with high Malaria transmission.…”

“…This results into a recurrent Malaria infection before clearing the HRP2 antigens of the previous one. This may not be the case for children living in low-transmission settings, who are much less likely to have had a recent Malaria infection [6]. This could also be suggestive of the high prevalence of Malaria in the high transmission season and low in the low transmission season.…”

Age and geographic patterns of Plasmodium falciparum malaria infection in a representative sample of children living in Burkitt lymphoma-endemic areas of northern Uganda

“…The use of RDT, which is more sensitive than TFM and provides information about population prevalence of malaria infection over a three- to four-week period [33] is a strength. The finding of similar patterns of pfPR when using results defined by TFM or both TFM and RDT suggests that the patterns reported here are likely valid.…”

A national health facility survey of malaria infection among febrile patients in Kenya, 2014

“…Patients who reported taking any anti-malarial treatment in the 2 weeks preceding the survey were excluded from the study because of the well-known persistence of HRP2 antigenaemia after treatment [45]. However, a recent study in Uganda reported a much longer HRP2 persistence period extending to a median of 35 to ≥42 days after treatment [46]. It is, therefore, possible that patients found positive in this survey, especially in the high endemic areas, may have been due to persistent HRP2 antigenaemia.…”