Performance of CareStart™ Malaria Pf/Pv Combo test for the diagnosis of Plasmodium falciparum and Plasmodium vivax infections in the Afar Region, North East Ethiopia

Abstract

Background : CareStart™ Malaria Pf/Pv Combo test has shown encouraging results for the diagnosis of P. falciparum and P. vivax infections in Ethiopia. Nevertheless, the performance of the test could be affected by different factors like gene polymorphisms, excess heat and humidity. Hence, evaluation of the performance of the test in different settings in Ethiopia is vital for the routine diagnosis of malaria. Objective : To evaluate the diagnostic performance of CareStartTM Malaria Pf/Pv Combo test for the diagnosis of P. falciparum and P. vivax infections in the Afar Region, Northeast Ethiopia. Methods : Finger prick blood samples were collected from a total of 1092 patients who had malaria symptoms and visited three different health facilities in the Afar Region. Giemsa-stained thin and thick blood smears were prepared and microscopically examined under 100 × magnifications for Plasmodium species identification and determination of parasitaemia. CareStart Malaria Pf/Pv Combo test was also performed as per the manufacturer's instructions. The sensitivity and the specificity of the test was determined using microscopy as gold standard. Results : The sensitivity and specificity of the test were 98.5% and 98.0% respectively, with a positive predictive value (PPV) of 91.7% and a negative predictive value (NPV) of 99.7% for the diagnosis of P. falciparum infection. The corresponding sensitivity and specificity for the diagnosis of P. vivax infection were 100% and 99.6% respectively, with PPV and NPV of 86.2% and 100%, respectively. Conclusion : The results of this study revealed high sensitivity and specificity of CareStartTM Malaria Pf/Pv Combo test for the diagnosis of both P. falciparum and P. vivax infections in the study area, though additional study may be needed in the most peripheral hottest areas of the region. [Ethiop. J. Health Dev. 2011;25(3):206-211]