Comparative Study of Malaria Diagnosis: Rapid Diagnostic Test (RDTs) Against Microscopy among Pregnant Women Attending Antenatal Clinic in Specialist Hospital, Sokoto

Background: Malaria is an infectious disease caused by a protozoan parasite of the genus Plasmodium. It was estimated that 219 million cases of malaria occur in 87 countries, with an estimated death of 435,000 in 2017 among pregnant women. Other species include P. ovale, P. vivax, and P. malariae is a blood parasite of human and is one of the major public health burdens in developing countries, particularly in Sub-Saharan Africa. It is estimated that about 3.5 billion people globally and 450 million people are thought to be ill as a result of such infections, the majority being children.

Aims: This study was aimed at comparing RDTs against microscopy in the detection of malaria parasite among pregnant women. Samples were collected and analyzed following cross-sectional comparative study design. It was conducted between Septembers to November 2019.

Study Design: This was a cross-sectional, comparative study

Place and Duration of Study: This study was conducted among patients attending Specialist Hospital Sokoto, Sokoto State, between March and November, 2019.

Methodology: A total of 106 participants were enrolled for the study. Standard parasitological examination was carried out on blood samples using microscopy followed by Rapid Diagnostic test (RDTs).

Results: Finding revealed, in this study, CareStart kit had sensitivity of 77.7%, specificity of 100s%. It is expected that any RDT used for malaria diagnosis should have a high sensitivity of 95% and specificity 97% (WHO, 2003); this is in contrast with the RDTs results in this study.

The false negative (FN) Carestart and SD-Bioline kits in this study were 10% and 21%, respectively using microscopy as the gold standard due to lack of sensitivity of RDTs at low parsitaemia compared to microscopy.

The false positive rate in this study for the Carestart and SD-Bioline kits are 0% and 0% respectively. Out of 106 patients screened, 35% and 24% tested positive for Plasmodiumfalciparum using Carestart and SD-Bioline RDTs respectively, while 45% were positive to malaria by microscopic examination. There was high prevalence of malaria parasite among age group 18-23 which is 42.2%.

Conclusion: It can be concluded that using microscopy is more time consuming compared to RDTs due to the fact that the time taken to read the results for RDTs is within five minutes and that of microscopy is higher compared to RDTs. Over all prevalence of malaria by microscopy was 42.5% while the prevalence of malaria by Carestart and SD-bioline was 33% and 22.6% respectively. Conventional microscopy remains the gold standard compared to RDTs according to this study with the level of its sensitivity and specificity which is higher than RDTs.