falciparum transmission, and this also could explain false-negative HRP-2 test results [27]. As already reported in numerous studies using HRP-2 tests, the specificity of the FirstSign Malaria Pf was extremely low and varied across seasons in our study. Indeed, the specificity was significantly reduced by half during the high malaria transmission season as compared to the low malaria season [from 63.7% (57.6–69.4) to 25.4% (20.5–31.0)]. Although the authors could anticipate that from literature, the value was, however, lower than that expected. Persistent HRP-2 antigenemia after effective treatment is one of the possible explanations of this low specificity. Indeed, in studies conducted
in Uganda and the Democratic Republic mTOR inhibitor of Congo where transmission is more perennial, it was shown that HRP-2 antigen could still be in the bloodstream
for a long time (more than 5 weeks) after successful treatment [28, 29]. The authors could not also exclude the fact that in this context with malaria high endemicity, a high proportion of individuals carried low parasite density not detected by microscopy despite the experience of microscopists and the quality control using double reading of each individual blood smear. Only the use of polymerase chain reaction (PCR) Ricolinostat price methods that have a sensitivity superior to microscopy to detect low parasites count would have helped to rule out this possibility [30]. These findings suggest
that when HRP-2 tests are used for case management in children less than 5 years living in area of intense and seasonal transmission check details of malaria, there is a risk of over-diagnosis, which may adversely affect the quality of care with the possibility of missing true cases of non-malaria febrile diseases, raising serious safety concerns. Also, the rational use of antimalarial drugs, which is one of the aims of introducing the use of RDT by CHWs, may be compromised. The likelihood ratios constitute one of the best ways to measure and express diagnosis accuracy [31]. They determine the accuracy of a positive or negative result and are independent of the prevalence of a disease conditions in populations [32]. The ratios the authors computed Tau-protein kinase for positive and negative tests to malaria transmission season suggested that the diagnostic efficiency of FirstSign Malaria Pf tests was highly dependent on the malaria transmission intensity. The lower the malaria transmission, the higher is the probability that patients with positive test results will have true malaria infection and vice versa. The high rate of false positivity highlights the need for not using a positive test result as an excuse for excluding other possible causes of fever; this requires some clinical skills that are not readily available among CHWs, who in these contexts are lay persons from the community.