RapiGEN BIOCREDIT Malaria Ag RDTs WHO Prequalification Study

Malaria continues to create a major health burden in the tropics especially in Africa. Introduction of Artemisinin-based combination therapy (ACT) has dramatically improved the outcomes of morbidity and mortality of malaria cases. Introduction of RDTs as well dramatically influenced cases detection hence treatment. The situation in Sudan is not different from the general picture in all Africa and witness great reduction of deaths from malaria since the introduction of ACT in 2005 (1). The national protocol depends now on Giemsa stained slides microcopy or certified RDTs for diagnosis and ACT as first and second line of treatment (2).

Recommendation by World Health Organization (WHO) on parasitological confirmation of malaria cases by microscopy or rapid diagnostic tests (RDTs) before treatment increased the use and availability of RDTs worldwide (3).

Rapid diagnostic tests, since their introduction in the late 90's, have dramatically improved our ability to control malaria. Most RDTs are based on histidine-rich protein 2 (PfHRP2) or lactate dehydrogenase (pLDH), which are present in Plasmodium falciparum only and all human-infecting Plasmodium species respectively (4). However, the gradual spread of hrp2/hrp3-deleted mutants in several endemic countries in South America, Asia and Africa exerts a substantial potential impact on the utility of HRP2-based RDTs for case management in these settings.

Plasmodium lactate dehydrogenase (pLDH), on the other hand, appears as a good alternative to HRP2 as it is an essential protein expressed by all human-infecting Plasmodium species; however, pLDH-based RDTs were shown to perform poorly at low parasitaemia, which is common among patients infected with P. vivax, P. malariae and P. ovale species as well as in asymptomatic infections. Therefore, it is less preferred in endemic-countries. In these settings, malaria microscopy holds its reign as the standard of reference thanks to its low direct cost and ability to detect, quantify, and differentiate malaria parasites. However, it is also labour-intensive, time-consuming and expertise-demanding.

With the aim of addressing these limitations, RapiGEN has developed novel malaria RDTs, in partnership with FIND and the Bill and Melinda Gates Foundation (BMGF). RapiGEN developed BIOCREDIT Malaria Ag Pf/Pv (pLDH/pLDH), BIOCREDIT Malaria Ag Pf (pLDH/HRP2) and BIOCREDIT Malaria Ag Pf.

These may provide added value compared to currently available malaria RDTs, especially in settings where current tests prove to be insufficient due to hrp2 deletion or high burden of P. vivax malaria.

Inclusion criteria

• Aged 5 years old or older
• Presenting at the study site with fever or a history of fever during the preceding 48 hours
• Freely agreeing to participate by providing informed consent (and assent, if applicable)

Exclusion criteria

• Presence of symptoms and signs of severe illness and/or central nervous system infections as defined by WHO guidelines