COMPARISON OF THREE TECHNIQUES FOR THE DIAGNOSIS OF MALARIA IN RESOURCE-LIMITED SETTINGS: A MINI-REVIEW

HTML Full Text

COMPARISON OF THREE TECHNIQUES FOR THE DIAGNOSIS OF MALARIA IN RESOURCE-LIMITED SETTINGS: A MINI-REVIEW

Neha Martin Honnalli and T. M. Desy *

Department of Biochemistry, KS Hegde Medical Academy, Nitte - DU, Mangalore, Karnataka, India.

---

ABSTRACT: Objective of this article is to review three techniques, routinely used rapid diagnostic tests (lateral flow immune chromatography) versus nucleic acid amplification test (NAT) versus Paper-based microfluidics for DNA diagnostics of Malaria, as diagnostic tests in detecting malarial infection among febrile illnesses, suspected of malaria. The major constraint for implementing NAT as a routine screening technique in India appears to be its high cost per test. There is a need to evaluate the technique and its cost-effectiveness as compared to RDT in the Indian setting as there is a scarcity of literature in this area.

---

Keywords: Malaria, RDT, NAT, DNA Microfluidics

---

INTRODUCTION: Malaria is a protozoan disease transmitted by the bite of infected Anopheles mosquitoes. It is transmitted in 106 countries containing 3 billion people and causes approximately 2000 deaths each day; mortality rates are decreasing as a result of highly effective control programs in several countries. Malaria has been eliminated from the United States, Canada, Europe, and Russia; in the late twentieth and early twenty-first centuries; however, its prevalence rose in tropical areas of Africa, Asia and Latin America, where it contributes as one of the world’s greatest public health problems.

Prevalence of Malaria: As per WHO report 2017, only eight percent of malaria cases were diagnosed in 2016 in India, which constituted six percent of the 216 million new cases globally.

The report also suggested that India was the third on the list of 15 countries which accounted for 80 percent of all malaria cases in the world in 2016. According to the report, only 8 percent of total malaria cases were detected in India due to poor surveillance mechanisms ¹.

According to World Health Organisation, in South East Asia Region, 70% of malaria cases were from India. Global estimate shows developing countries report a maximum number of cases of malaria, with the majority of infected people living in urban India. When we consider the prevalence of malaria in Karnataka, a study reports that Dakshina Kannada, a southern coastal district of Karnataka State, contributes almost 50% of the cases to the state malaria profile ².

As screening techniques used for malarial parasite detection have their own drawbacks, it is justifiable to compare their sensitivity, specificity, and cost-effectiveness.

Diagnosis of Malaria: The Giemsa-stained blood slide using thin and thick smears for malaria parasites has been the gold standard method for nearly a century ³. No alternative method still could be established to replace this universally accepted gold standard method. This technique to confirm the clinical suspicion of malaria is labor-intensive ⁴ and sometimes unreliable due to lack of skilled microscopists, limited supplies, inadequate maintenance of microscopes and reagents and inadequate or absence of quality-control systems ⁵.

In recent time, lateral flow immunochromato-graphic based rapid diagnostic tests (RDT) have been developed for the diagnosis of suspected malaria patients and are widely used in remote areas across the world ⁶. Rapid diagnostic test (RDT) kits offer great potential for the immediate diagnosis of malaria infections. Rapid diagnosis ensures prompt treatment, especially in rural settings. RDTs are lateral flow immunochromato-graphic tests that detect Plasmodium parasite antigens in blood ⁷. Three antigens are detected by current RDTs: histidine-rich protein 2 (HRP2), lactate dehydrogenase (LDH) and aldolase ⁸.

However, the performance of such assays has been limited by their generation of false-positive results, which occur when nonspecific biomolecules present in the blood, such as the rheumatoid factor, for example, react with the test antigens. Technical issues linked to capillary flow and to reagent stability in challenging environmental conditions, including high humidity and temperature ⁹, have also affected the reliability of RDT immuno-diagnostics. Test sensitivities are often only 70 to 75% in the field, despite being much higher in well-controlled laboratory conditions.

Nucleic Acid Testing (NAT) and Malaria: Nucleic acid amplification-based tests (NAATs) provide a promising approach for DNA-based malaria diagnostics. These tests both amplify and detect the genomic material of the parasite directly from a patient sample, providing a sensitive, species-specific test that will also identify whether an infection is current rather than historical. In addition, the signal used for detection does not depend on the patients’ immune responses, and the technique can be both quantitative and more accurate than Immuno-RDTs ¹⁰.

Several nucleic acid testing (NAT) approaches for the diagnosis of human malaria infection have been developed in the past two decades ¹¹. Studies suggest that NAT can detect and quantify parasites more sensitively and precisely than by microscopy or rapid diagnostic tests (RDTs). NAT is valuable for controlled human malaria infection studies of investigational drug and vaccine candidates, for drug efficacy studies as well as for epidemiological surveillance ¹². Parasite load can be quantified by NAT assay 2–6 days earlier than microscopy ¹³.

In many reference laboratories, PCR-based amplification assays remain the gold-standard NAAT ¹⁰, although the requirement for trained staff and external power has limited their application in areas with reduced resources.

In recent times, the real-time PCR method has been established for the quantitative detection of malaria parasites ¹⁴. Real-time PCR is reliable and yields high sensitivity and specificity when compared with microscopy or nested PCR ¹⁵.

In a Chinese study, Yan et al., compared the sensitivities of RDTs and microscopy with that of nucleic acid testing by nested PCR. The study concluded that Compared to PCR, both microscopy and RDTs had lower sensitivities, especially for P. vivax diagnosis ¹⁶. A study by Alam et al., in Bangladesh compared the sensitivities of rapid diagnostic tests and nucleic acid amplification tests, and the study concluded that SYBR Green-based real-time PCR assay could be used as an alternative gold standard method in a reference setting. Commercially-available RDTs used in the study are quite sensitive and specific in detecting P. falciparum, although their sensitivity in detecting P. vivax was not satisfactory compared to the real-time PCR assay ¹⁷. Perandin et al., reported better sensitivity with RT PCR in detecting malarial parasites as compared to RDT ¹⁸.

The major constraint for implementing NAT as a routine screening technique in India appears to be its high cost per test and the time duration required.

Use of a device, Paper-based microfluidics for DNA diagnostics that uses origami to enable multiplexed, sensitive assays that may be superior to PCR-based laboratory assays and provide high-quality, fast precision diagnostics for malaria. The paper-based microfluidic technology combines vertical flow sample-processing steps, including paper folding for whole-blood sample preparation, with an isothermal amplification and lateral flow detection, incorporating a simple visualization system. Aim of the study would be to review the diagnostic sensitivity and specificity of paper-based microfluidics for DNA diagnostics of malaria. We hypothesize that advanced, low-cost DNA-based sensors can be implemented in underserved communities at the point of need cost-effectively.

Cost-effectiveness Analysis: Cost-effectiveness analysis is an important tool to assist clinicians, scientists, and policymakers in determining the efficiency of healthcare interventions, guiding societal decision-making on the financing of healthcare services, and establishing research priorities. Diverse approaches to synthesize evidence have been considered in biomedical research, including economic evaluations of healthcare interventions ^{10, 19}. At the same time, decision-making in health care requires an understanding of the state of economic evaluation at a national level, where the completeness of the reporting is generally less well understood but where specific priorities are often set. Cost-effectiveness analysis (CEA) compares two diagnostic tests, where the costs are identified in monetary terms and the outcomes in non-monetary terms.

Measurement of cost-effectiveness could be made in two different ways:

1. ACER – Average Cost-Effectiveness Ratio
2. ICER – Incremental Cost-Effectiveness Ratio

It helps a decision-maker to compare one treatment/diagnostic test to another, thereby quantifying the opportunity cost of decisions.

Future Research Perspective: The study that can demonstrate that paper-based microfluidic devices can deliver precision diagnostics for malaria in low-resource, underserved settings with a sensitivity that is higher than that of the current malaria diagnostic tests used in the field and with performance that is similar to that of a laboratory-based real-time PCR test is the need of the hour. These diagnostic devices could have a meaningful, positive impact on the provision of mass screening and treatment in campaigns to eliminate the infectious disease. These campaigns have had limited success to date in combating malaria transmission, which has been linked to the inability of current field-based diagnostic tools to detect low-level infections. Thus, the availability of easy-to-use, highly sensitive NAATs, such as those provided by this device, could potentially detect these missed cases and reduce the opportunity for transmission. This would have a significant impact on public health in areas where malaria is highly prevalent.

Impact of the Study: The study may demonstrate that paper-based microfluidic devices can deliver precision diagnostics for malaria in low-resource, underserved settings with a sensitivity that is higher than that of the current malaria diagnostic tests used in the field and with performance that is similar to that of a laboratory-based real-time PCR test. These diagnostic devices may have a meaningful, positive impact on the provision of mass screening and treatment in campaigns to eliminate the infectious disease. These campaigns have had limited success to date in combating malaria transmission, which has been linked to the inability of current field-based diagnostic tools to detect low-level infections. Thus, the availability of easy-to-use, highly sensitive NAATs, such as those provided by this device, could potentially detect these missed cases and reduce the opportunity for transmission. This would have a significant impact on public health in areas where malaria is highly prevalent. It could also inform current thinking within governments and non-governmental organizations concerning improvements in the effectiveness and cost-effectiveness of prophylactic approaches to control diseases (where new precise diagnostic tools are required to rapidly and accurately target where treatment is needed).

Economic assessments of diagnostic tests are inherently difficult than assessments of therapeutic interventions because of uncertainty about the relation between diagnosis and end result or outcomes of care. Towards the end, this study would evaluate the economic feasibility of the introduction of paper microfluidic technique for DNA diagnostics as a diagnostic test for malaria. The economic evaluation of the cost-effectiveness of NAT using the Yield of the NAT test vis a vis the conventional RDT test would have profound implications with respect to policymaking and utility of the test for diagnosing individuals with malaria. If the malarial infection detection rate by paper microfluidic technique for DNA diagnostics were to be proven to be beneficial, it would pave new roads for early diagnosis of the disease by providing scientific evidence for possibly implementing this test as a useful diagnostic test. This study would help in planning out further strategies for the effective management and treatment of individuals detected by the test. It would also dive into newer research areas to establish the subsequent decrease in the morbidity and mortality associated with malaria given appropriate facilities for early treatment after detection would be mandated at the policy level.

CONCLUSION: The Implications of this study from the patient’s perspective would mean early diagnosis which forms the tenet of control of the disease by increasing the yield. Early diagnosis at community level would translate into application of efficient prevention mechanisms to spread the infection. The cost effectiveness analysis would provide scientific basis for adoption of the best test for the diagnosis, given the economic feasibility of the study. Early diagnosis will aid the clinician in providing timely treatment by reducing the morbidity and mortality due to malarial infection.

National Relevance: The Implications of this study from the patient’s perspective would mean early diagnosis, which forms the tenet of control of the disease by increasing the yield. Early diagnosis at community level would translate into application of efficient prevention mechanisms to spread the infection. The cost-effectiveness analysis would provide a scientific basis for the adoption of the best test for the diagnosis, given the economic feasibility of the study. Early diagnosis will aid the clinician in providing timely treatment by reducing morbidity and mortality due to malarial infection.

ACKNOWLEDGEMENT: Nil

CONFLICTS OF INTEREST: Nil

REFERENCES:

1. WHO Malaria report 2017. www.who.int/malaria/ publications/world-malaria-report 2017/en/
2. Shivakumar, Rajesh BV, Kumar A, Achari M, Deepa S and Vyas N: Malarial trend in Dakshina Kannada, Karnataka: An epidemiological assessment from 2004 to 2013. Indian journal of health sciences and biomedical research KLEU 2015; 8(2): 91-94.
3. Gitta B and Kilian N: Diagnosis of Malaria Parasites Plasmodium spp. in Endemic Areas: Current Strategies for an Ancient Disease. Bio-Essays 2019; 42(1): 1-12.
4. Coleman RE, Maneechai N, Rachaphaew N, Kumpitak C, Miller RS, Soyseng V, Thimasarn K and Sattabongkot J: Comparison of field and expert laboratory microscopy for active surveillance for asymptomatic Plasmodium falciparum and Plasmodium vivax in western Thailand. Am J Trop Med Hyg 2002; 67: 141-44.
5. Brown H, Azike CA: A comparative study on malaria rapid diagnostic kit and conventional Giemsa stained blood film microscopy. International Journal of Science and Research 2014; 3(12): 1433-5.
6. van den Hoogen L and Drakeley C: Malaria Diagnostic Platform, Antibody Detection. In: Hommel M., Kremsner P. (eds) Encyclopedia of Malaria. Springer, New York, NY. 2015.
7. Orish VN, De-Gaulle VF and Sanyaolu AO: Interpreting rapid diagnostic test (RDT) for Plasmodium falciparum. BMC Research Notes 2018; 11(1): 1-6.
8. Wanja EW: Field evaluation of diagnostic performance of malaria rapid diagnostic tests in western Kenya. Malar J 2016; 15: 456.
9. Feleke DG, Tarko S and Hadush H: Performance comparison of CareStart™ HRP2/ pLDH combo rapid malaria test with light microscopy in north-western Tigray, Ethiopia: A cross-sectional study. BMC Infect Dis 2017; 17: 399.
10. Reboud J, Xu G and Garrett A: Paper-based microfluidics for DNA diagnostics of malaria in low resource underserved rural communities. Proc NatlAcad Sci U S A. 2019; 116(11): 4834-42.
11. Baylis SA, Wallace P, McCulloch E, Niesters HGM, Nübling CM: Standardization of nucleic acid tests: the approach of the World Health Organization. Journal of Clinical Microbiology 2019; 57 (1): e01056-18.
12. Murphy SC, Hermsen CC, Douglas AD, Edwards NJ, Petersen I, Fahle GA, Adams M, Berry AA, Billman ZP, Gilbert SC and Laurens MB: External quality assurance of malaria nucleic acid testing for clinical trials and eradication surveillance. PloS One 2014; 9(5): e97398.
13. Hodgson SH, Douglas AD, Edwards NJ, Kimani D, Elias SC, Chang M, Daza G, Seilie AM, Magiri C, Muia A and Juma EA: Increased sample volume and use of quantitative reverse-transcription PCR can improve prediction of liver-to-blood inoculum size in controlled human malaria infection studies. Malaria Journal 2015; 14(1): 1-9.
14. Haanshuus CG, Mørch K, Blomberg B, Strøm GE, Langeland N, Hanevik K and Mohn SC: Assessment of malaria real-time PCR methods and application with focus on low-level parasitaemia. PloS One 2019; 14(7): e0218982.
15. Han TZ, Han KT, Aye KH, Hlaing T, Thant KZ and Vythilingam I: Comparison of microscopy and PCR for the detection of human Plasmodium species and Plasmodium knowlesi in southern Myanmar. Asian Pacific Journal of Tropical Biomedicine 2017; 7(8): 680-5.
16. Alam MS, Mohon AN, Mustafa S, Khan WA, Islam N, Karim MJ, Khanum H, Sullivan DJ and Haque R: Real-time PCR assay and rapid diagnostic tests for the diagnosis of clinically suspected malaria patients in Bangladesh. Malaria Journal 2011; 10: 175.
17. Perandin F, Manca N, Calderaro A, Piccolo G, Galati L, Ricci L, Medici MC, Arcangeletti MC, Snounou G, Dettori G and Chezzi C: Development of a realtime PCR assay for detection of Plasmodium falciparum, Plasmodium vivax, and Plasmodium ovale for routine clinical diagnosis. J Clin Microbiol 2004; 42: 1214-19.
18. Wardhani P, Butarbutar TV, Adiatmaja CO, Betaubun AM and Hamidah N: Performance comparison of two malaria rapid diagnostic test with real time polymerase chain reaction and gold standard of microscopy detection method. Infectious Disease Reports 2020; 12(11): 56-60.
19. Catalá-López F, Ridao M, Alonso-Arroyo A, García-Altés A, Cameron C, González-Bermejo D, Aleixandre-Benavent R, Bernal-Delgado E, Peiró S, Tabarés-Seisdedos R and Hutton B: The quality of reporting methods and results of cost-effectiveness analyses in Spain: a methodological systematic review. Systematic Reviews 2016; 5(1): 1-1.
    

    ---

    How to cite this article:

    Honnalli NM and Desy TM: Comparison of three techniques for the diagnosis of malaria in resource limited settings: a mini review. Int J Pharm Sci & Res 2022; 13(1): 125-29. doi: 10.13040/IJPSR.0975-8232.13(1).125-29.

    ---

    All © 2022 are reserved by the International Journal of Pharmaceutical Sciences and Research. This Journal licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.