Hemozoin detection may provide an inexpensive, sensitive, 1-minute malaria test that could revolutionize malaria screening

Abstract

Malaria remains widespread throughout the tropics and is a burden to the estimated 3.5 billion people who are exposed annually. The lack of a fast and accurate diagnostic method contributes to preventable malaria deaths and its continued transmission. In many areas diagnosis is made solely based on clinical presentation. Current methods for malaria diagnosis take more than 20 minutes from the time blood is drawn and are frequently inaccurate. The introduction of an accurate malaria diagnostic that can provide a result in less than 1 minute would allow for widespread screening and treatment of endemic populations, and enable regions that have gained a foothold against malaria to prevent its return. Using malaria parasites' waste product, hemozoin, as a biomarker for the presence of malaria could be the tool needed to develop this rapid test.

Keywords: Magneto-Optical Detection; Malaria; RDT; elimination; hemozoin; rapid diagnostic.

Figure 1. Speed, Cost, and Minimum Level of Parasite Detection by Method

These graphs show the time it takes to run the procedure, cost for running each sample, and the minimum amount of parasites each method can detect.^, The accuracy of each method and startup costs vary widely within each method and therefore are not shown. Malaria detection methods run the gamut from very inexpensive and inaccurate (i.e., thin smear microscopy) to the highly accurate but extremely slow (i.e., PCR). Thin smear microscopy is only effective for speciation of malaria parasites once a positive sample has been found. Flow cytometric methods have improved and offer the potential to screen for multiple types of infections at once, but presently they require expensive machinery and highly skilled technicians. RDT dipstick tests eliminate the need for highly trained personnel at the expense of cost and accuracy. RDTs are ineffective below 200 parasites per microliter. Magneto-Optical detection methods currently in development have the potential to be fast (<1 minute), inexpensive, and highly sensitive for <5 parasites per microliter. Magnetic extraction methods such as MACS columns or Magnetic Deposition Method are useful for research purposes but at over $10 per sample with processing times of more than one hour, they are not feasible for malaria screening and therefore are not included in this comparison.