• 1

    Moody A, 2002. Rapid diagnostic tests for malaria parasites. Clin Microbiol Rev 15 :66–78.

  • 2

    World Health Organization, 1999. New Perspectives: Malaria Diagnosis. Report of a Joint WHO/USAID Informal Consultation, October 25–27, 1999. Geneva. WHO/MAL/2000. 1091.

  • 3

    Beadle C, Long GW, Weiss WR, McElroy PD, Maret SM, Oloo AJ, Hoffman SL, 1994. Diagnosis of malaria by detection of Plasmodium falciparum HRP-2 antigen with a rapid dipstick antigen-capture assay. Lancet 343 :564–568.

    • Search Google Scholar
    • Export Citation
  • 4

    Durrheim DN, la Grange JJP, Govere J, Mngomezulu NM, 1998. Accuracy of a rapid immunochromatographic card test for Plasmodium falciparum in a malaria control programme in South Africa. Trans R Soc Trop Med Hyg 92 :32–33.

    • Search Google Scholar
    • Export Citation
  • 5

    Garcia M, Kirimoama S, Marlborough D, Leafasia J, Rieckmann KH, 1996. Immunochromatographic test for malaria diagnosis (letter). Lancet 347 :1549.

    • Search Google Scholar
    • Export Citation
  • 6

    Singh N, Valecha N, Sharma VP, 1997. Malaria diagnosis by field workers using an immunochromatographic test. Trans R Soc Trop Med Hyg 91 :396–397.

    • Search Google Scholar
    • Export Citation
  • 7

    Wongsrichanalai CN, Tulyayon S, Thanoosingha N, Laoboonchai A, Thaimasarn K, Brewer TG, Happner DG, 1999. Comparison of a rapid field immunochromatographic test to expert microscopy for the detection of Plasmodium falciparum asexual parasitemia in Thailand. Acta Trop 73 :263–273.

    • Search Google Scholar
    • Export Citation
  • 8

    Iqbal J, Sher A, Hira PR, Al-Owaish R, 1999. Comparison of the OptiMAL test with PCR for diagnosis of malaria in immigrants. J Clin Microbiol 39 :3644–3646.

    • Search Google Scholar
    • Export Citation
  • 9

    Iqbal J, Hira PR, Sher A, Al-Enezi AA, 2001. Diagnosis of imported malaria by Plasmodium lactate dehydrogenase (pLDH) and histidine-rich protein 2 (PfHRP-2)-based immunocapture assays. Am J Trop Med Hyg 64 :20–23.

    • Search Google Scholar
    • Export Citation
  • 10

    Moody A, Hunt-Cooke A, Gabbett E, Chiodini P, 2000. Performance of the OptiMAL malaria antigen capture dipstick for malaria diagnosis and treatment monitoring at the Hospital for Tropical Diseases, London. Br J Haematol 109 :891–894.

    • Search Google Scholar
    • Export Citation
  • 11

    Palmer CJ, Lindo JF, Klaskala WI, Quesada JA, Kaminsky R, Baum MK, Ager AL, 1998. Evaluation of the OptiMAL test for rapid diagnosis of Plasmodium vivax and Plasmodium falciparum malaria. J Clin Microbiol 36 :203–206.

    • Search Google Scholar
    • Export Citation
  • 12

    Cho-Min-Naing, Gatton ML, 2002. Performance appraisal of rapid on-site malaria diagnosis (ICT Malaria Pf/Pv test) in relation to human resources at village level in Myanmar. Acta Trop 81 :13–19.

    • Search Google Scholar
    • Export Citation
  • 13

    Dyer ME, Tjitra E, Currie BJ, Anstey NM, 2000. Failure of ‘pan malarial’ antibody of the ICT Malaria Pf/Pv immunochromatographic test to detect symptomatic Plasmodium malariae infection. Trans R Soc Trop Med Hyg 94 :518.

    • Search Google Scholar
    • Export Citation
  • 14

    Huong NM, Davis TME, Hewitt S, Huong NV, Uyen TT, Nhan DH, Cong LD, 2002. Comparison of three antigen detection methods for diagnosis and therapeutic monitoring of malaria: a field study from southern Vietnam. Trop Med Int Health 7 :304–308.

    • Search Google Scholar
    • Export Citation
  • 15

    Jelinek T, Grobusch MP, Harms G, 2001. Evaluation of a dipstick test for the rapid diagnosis of imported malaria among patients presenting within the Network TropNetEurop. Scand J Infect Dis 33 :752–754.

    • Search Google Scholar
    • Export Citation
  • 16

    Warhurst DC, Williams JE, 1996. Laboratory diagnosis of malaria: ACP Broadsheet No. 148. J Clin Pathol 49 :533–538.

  • 17

    World Health Organization, 1996. Management of Uncomplicated Malaria and the Use of Antimalarial Drugs for the Protection of Travelers. Report of an Informal Consultation. September 18–21, 1995. Geneva. WHO/MAL/96. 1075: 98.

  • 18

    Jelinek T, Grobusch MP, Nothdurft H, 2000. Use of dipstick test for the rapid diagnosis of malaria in non-immune travelers. J Travel Med 7 :175–179.

    • Search Google Scholar
    • Export Citation
  • 19

    Ferro BE, Gonzalez IJ, Carvajal F, Palma GI, Saravia NG, 2002. Performance of OptiMAL(R) in the diagnosis of Plasmodium vivax and Plasmodium falciparum infections in a malaria referral center in Colombia. Mem Inst Oswaldo Cruz 97 :731–735.

    • Search Google Scholar
    • Export Citation
  • 20

    Shiff CJ, Premji Z, Minjas JN, 1993. The rapid manual ParaSight F test: a new diagnostic tool for Plasmodium falciparum infection. Trans R Soc Trop Med Hyg 87 :646–648.

    • Search Google Scholar
    • Export Citation
  • 21

    Shiff CJ, Minjas JN, Premji Z, 1994. The ParaSight F test: a simple rapid manual dipstick test to detect Plasmodium falciparum infection. Parasitol Today 10 :494–495.

    • Search Google Scholar
    • Export Citation
  • 22

    Grobusch MP, Alpermann U, Schwenke S, Jelinek T, Warhurst DC, 1999. False-positive rapid tests for malaria in patients with rheumatoid factor (letter). Lancet 353 :297.

    • Search Google Scholar
    • Export Citation
  • 23

    Piper R, Lebras J, Wentworth L, Hunt-Cooke A, Houze S, Chiodini P, Makler M, 1999. Immunocapture diagnostic assays for malaria using Plasmodium lactate dehydrogenase (pLDH). Am J Trop Med Hyg 60 :109–118.

    • Search Google Scholar
    • Export Citation
  • 24

    Fryauff DJ, Purnomo, Sutamihardja MA, 2000. Performance of the OptiMAL assay for detection and identification of malaria infections in asymptomatic residents of Irian Java, Indonesia. A J Trop Med Hyg 63 :139–145.

    • Search Google Scholar
    • Export Citation
 
 
 

 

 
 
 

 

 

 

 

 

 

PERFORMANCE OF THE OPTIMAL TEST FOR MALARIA DIAGNOSIS AMONG SUSPECTED MALARIA PATIENTS AT THE RURAL HEALTH CENTERS

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  • 1 Department of Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait; Malaria Control Department, Lahore, Punjab, Pakistan

The OptiMAL test detects both Plasmodium falciparum and P. vivax malaria infections. In this study, we evaluated the performance of the OptiMAL test at the Basic Health Units (BHUs) and the District Health Quarter (DHQ) Center in rural villages of Punjab, Pakistan that provide minimal health services. Two sets of blood specimens obtained from 930 suspected malaria patients attending these BHUs were tested at BHUs and the DHQ Center by microscopy and the OptiMAL test. At the BHUs, 231 (25%) of the patients were positive by microscopy and 278 (30%) patients tested positive by the OptiMAL test. At the DHQ Center, microscopic analysis of a second set of specimens from the same patients confirmed the malaria infection in 386 (42%) patients and the OptiMAL test result was positive in 300 (32%) patients. To determine the performance of OptiMAL test at the BHUs and the DHQ Center, all data were compared with microscopy results obtained at the DHQ Center. The OptiMAL test results for P. falciparum at the BHUs were comparable to those of the OptiMAL test at the DHQ Center. However, the sensitivity, positive predictive value (PPV), and negative predictive value (NPV) of the OptiMAL test were considerably lower for P. vivax infections than for P. falciparum infections, irrespective of whether the test was performed at the BHUs or at the DHQ Center (P. falciparum: sensitivity = 78–85%, PPV = 89–97%, NPV = 96–98%; P. vivax: sensitivity = 61–76%, PPV = 88–95%, NPV = 90–93%). The OptiMAL test also detected a number of false-positive and false-negative results at both the BHUs and the DHQ Center. The false-positive results ranged from 1% to 2%; however, the number of false-negative results was much higher (BHUs: P. falciparum = 22%, P. vivax = 39%; DHQ Center: P. falciparum = 15%, P. vivax = 24%). In conclusion, these results, when combined with other advantages of the OptiMAL test, suggest that this test can be used by relatively inexperienced persons to diagnose malaria infection in rural areas where facilities for microscopy are not available.

INTRODUCTION

In patients with malaria, a prompt and accurate diagnosis is the key to effective disease management. Microscopic examination of stained blood films remains the standard diagnostic method.1 However, correct interpretation of blood films requires considerable expertise that is not necessarily available at peripheral medical centers in non-endemic countries. Thus, availability of a simple and accurate test could greatly aid the diagnosis of malaria infection in remote areas where health facility coverage is low and the population is at high risk of contracting malaria.1,2

Antigen-detection methods have recently been introduced for situations where reliable microscopy may not be available. In the case of infection with Plasmodium falciparum, these new rapid methods are based on detection of histidine-rich protein-2 (PfHRP-2; ICT Malaria Pf and ParaSight-F)2–7 or parasite lactate dehydrogenase (pLDH; OptiMAL).8–11 Species-specific pLDH isoforms have been used to develop a test for P. vivax (OptiMAL). Plasmodium vivax can also be detected by detection of antibodies against pan-malarial antigen in the absence of those against HRP-2 (ICT Malaria Pf/Pv).12–15 The sensitivity and specificity of each of these tests have been assessed in a range of clinical situations.

This study was conducted at the Basic Health Units (BHUs) in rural areas of Punjab, Pakistan where malaria infection is endemic. These BHUs form the tertiary health care centers and lack the services of an expert microscopy to confirm malaria infection. The study also investigated the operational aspect of this rapid non-microscopic test by health workers with minimal technical expertise in diagnosing malaria infection.

MATERIALS AND METHODS

Patients and study design.

This study was conducted at the BHUs that form the tertiary clinics situated in rural areas of Punjab, Pakistan for the provision of basic health care services. A trained Lady Health Visitor (LHV) and a volunteer health worker (VHW), both of whom are not experts in microscopy, service the BHUs. Residents attend the BHUs located in their village. Three BHUs in central Punjab, Pakistan, where malaria infection is endemic, were selected to participate in this study. The research team provided appropriate training in the use of OptiMAL kits to LHVs and the VHW. The selection of the OptiMAL test in this study was based on performance of this test and our experience in handling this test at the Microbiology Unit, Faculty of Medicine, of the University of Kuwait.8,9

Nine hundred thirty individuals 2–55 years of age who were attending the BHUs with a history of fever and possible malaria infection were included in the study. Individuals that have been treated for malaria in the previous four weeks were excluded from the study. For each individual, paired 0.5-mL peripheral blood samples were taken in a pre-heparinized Eppendorf tube (Eppendorf-Netheler-Hinz, GmbH, Hamburg, Germany), One set of samples was used to make blood films for microscopy and for the OptiMAL test at the BHUs, while the second sample was coded and sent to the District Health Quarter (DHQ) Center for OptiMAL testing and microscopic analysis. The research team also examined randomly selected Giemsa-stained blood smears and stained OptiMAL strips at the Microbiology Unit, Faculty of Medicine of the University of Kuwait. The microscopic analysis of Giemsa-stained smears and the OptiMAL tests at the BHUs and the DHQ Center were performed in double-blind manner. Informed consent to participate in the study was obtained from the participants and the local Ethical Committee reviewed and approved the study.

Microscopy of Giemsa-stained blood films.

Thick and thin blood films were made immediately after blood collection and stained with 10% Giemsa for 10 minutes and analyzed by light microscopy. A minimum of 200 consecutive fields was counted in the thick blood film before classifying a slide as negative. Parasites in thick blood films were counted against 200–500 white blood cells. The parasite density was estimated assuming 8,000 white blood cells/μL of blood.1,16,17

OptiMAL test.

The OptiMAL test (Flow, Inc., Portland, OR) was performed as previously reported following the manufacturer’s instructions.8,9 Briefly, one drop of whole blood was mixed with two drops of lysis buffer A, which disrupts the red blood cells and releases the pLDH. The specimens were then allowed to migrate to the top of the pLDH strip. After eight minutes, the strips were placed in washing buffer B, which clears the hemoglobin from the strip. Interpretation of the test results was performed immediately. A negative control sample taken from an individual who had not been exposed to malaria for three years, was included with each batch tested. In the pLDH assay, there are two diagnostic zones of reaction containing different antibodies. The first diagnostic zone contains a monospecific antibody that recognizes only P. falciparum if it is present. The second diagnostic zone contains a pan-specific antibody immediately above the first zone. This monoclonal antibody recognizes the pLDH isoforms of P. vivax. A third reaction zone containing a pan-specific monoclonal antibody is present at the top of the test strip and serves as a positive control for the assay. The test can be completed in 10–15 minutes.

Statistical analysis.

Data was collected and analyzed using the SPSS (SPSS, Chicago, IL) statistical program. For sensitivity and specificity, the test kits were compared with the microscopic results of Giemsa-stained smears at the DHQ Center. Sensitivity was calculated as the proportion of positive test results obtained among samples containing malaria parasites by microscopy; specificity was calculated as the proportion of negative test results obtained among samples whose thick blood films were negative. Positive predictive values (PPVs) and negative predictive values (NPVs) were calculated as the proportion of true positive results among all positive reactors and as the proportion of true negative results among all negative reactors, respectively.

RESULTS

Blood specimens were collected in duplicate from 930 suspected cases of malaria. All of these patients presented with a history of fever of 2–3-days duration and none of them had a history of antimalarial therapy during the last four weeks. One set of specimens was tested for malaria infection by microscopy and the OptiMAL test at the BHUs and the other set was tested at the DHQ Center. The results of microscopy of Giemsa-stained blood films and the OptiMAL test at both the BHUs and the DHQ Center are summarized in Table 1. At the BHUs, 231 (25%) of the patients were positive for malarial parasites by microscopy (92 for P. falciparum, 126 for P. vivax, and 13 for mixed infections of both of these parasites), while 278 (30%) patients tested positive by the OptiMAL test (115 for P. falciparum, 144 for P. vivax, and 19 for mixed infections). At the DHQ Center, microscopy of the second set of specimens from the same patients confirmed malaria infection in 386 (42%) patients (131 for P. falciparum, 206 for P. vivax, and 49 for mixed infections), while 300 patients tested positive by the OptiMAL test (114 for P. falciparum, 164 for P. vivax, and 22 for mixed infections). The performance of OptiMAL test in detecting malaria infection at the BHUs and the DHQ Center was compared with the microscopic results obtained at the DHQ Center. The staff at the BHUs detected malaria infection by microscopy in 60% of the patients (70% for P. falciparum, 61% for P. vivax, and 26% for mixed infections). However, when using the OptiMAL test, the same staff detected malaria infection in 72% of the patients (88% for P. falciparum, 70% for P. vivax, and 39% for mixed infections).

At the BHUs, the number of malaria cases confirmed by the OptiMAL test was significantly higher (P < 0.05) than that by microscopy. It is notable that the OptiMAL test results for P. falciparum at the BHUs were comparable with those of the OptiMAL test at the DHQ Center (Table 1). As expected, the OptiMAL test had a lower sensitivity for lower parasitemias when compared with microscopy (Table 1), but it showed better performance than microscopy at the BHUs even at lower parasitemias. A number of false-positive and false-negative results were detected by the OptiMAL test at the BHUs and the DHQ Center (Table 2). The OptiMAL test failed to detect infection in 109 patients, 80 (39%) with P. vivax and 29 (22%) with P. falciparum, that were positive by microscopy at the DHU Center (Table 2). Of particular concern, however, were high parasitemias in two patients that were not detected by the OptiMAL test at the DHQ Center. The sensitivity and the NPV of the OptiMAL test were considerably lower for P. vivax infections than for P. falciparum infections, irrespective of whether the test was performed by the inexperienced staff at the BHUs or by the trained technical staff at the DHQ Center (P. falciparum: sensitivity = 78–85%, PPV = 89–97%, NPV = 96–98%; P. vivax: sensitivity = 61–76%, PPV = 88–95%, NPV = 90–93%, Table 3). A total of 100 randomly selected blood specimens were also tested at the Microbiology Unit, Faculty of Medicine, of the University of Kuwait. Both microscopy of Giemsa-stained blood smears and the OptiMAL test result for P. falciparum and P. vivax was comparable with the results obtained at the DHQ Center. However, 19 additional malaria cases (11 with P. falciparum and 8 with P. vivax) were detected by microscopy at the University of Kuwait that were negative by microscopy at the BHUs.

The procedural aspects of the OptiMAL test were rapid and easy to follow for the staff at the BHUs. The comparative performance, requirements, and technical specifications of the OptiMAL test and microscopy show that the OptiMAL test presents technical and operational advantages over microscopy (Table 4).

DISCUSSION

The recent development of easy, rapid, and accurate tests for the detection of malaria infection is highly commendable. One of the major goals of developing such tests was that these should be handled with ease and accuracy by relatively unskilled staff in the rural villages where microscopy may not be available for diagnosing malaria infection.1,2 This study was designed to investigate the performance of the OptiMAL test, relative to microscopy, at the BHUs in rural villages that have minimal health services. As such, the definitive diagnosis of malaria infection in such areas is severely compromised by the lack of microscopy. The choice to include the OptiMAL test in the study was based on its capacity to detect both P. falciparum and P. vivax infections and its performance in various epidemiologic settings.8,9 The study design was such to make a direct comparison of the performance of microscopy and the OptiMAL test when conducted by persons with different technical experience. The staffs at the BHUs tested one set of the duplicate specimens taken from the patients and experienced technical staff at DHQ Center tested the other set. Our data confirm that the sensitivity of microscopy for malarial parasites was very low (25%) at the BHUs compared with that (42%) at the DHQ Center. Compared with microscopy at the DHQ Center, the staff at the BHUs failed to detect at least 30% of the P. falciparum and 39% of the P. vivax malaria cases. The sensitivity was further lowered at parasitemias < 500/μL; 58% of the infections were not detected by microscopy at the BHUs. The staff at the DHQ Center was more experienced in making better blood slides. Therefore, it would be expected that the quality of the blood slides made by staff at the DHQ Center is higher than that of the BHUs, and that this difference may affect the reading of slides, resulting in a lower sensitivity of microscopy at the BHUs.

Compared with microscopy at the DHQ Center, the performance of the OptiMAL test was comparable to that at the BHUs and the DHQ Center (88% and 87%, respectively). The OptiMAL test was more sensitive in detecting P. falciparum infections than P. vivax infections. This trend, as well as the actual values for sensitivity, specificity, PPV, and NPV, was consistent with the results of similar studies.1,6,9–11,18 However, some studies have reported that the sensitivity of the OptiMAL test in detecting malaria infections was better for P. vivax than for P. falciparum.14,19

The OptiMAL test detected a number of false-positive and false-negative results at both the BHUs and the DHQ Center. False-positive results ranged between 1% and 2%; however, the number of false-negative results detected was much higher (BHUs: P. falciparum = 22%, P. vivax = 39%; DHQ Center: P. falciparum = 15%, P. vivax = 24%). False-positive OptiMAL results have also been previously reported.8,9,12 False-positive cases could occur if patients had a previous recent infection with malaria,6,20,21 or if patients had circulating rheumatoid factor.12,15,22 However, it is unlikely that these factors account for all such cases. It is more likely that most of these OptiMAL-positive cases were true positive results that were not detected by microscopy at the BHUs due to lack of microscopy. In addition, false-negative results by microscopy can occur if patients have undertaken self-medication prior to presentation. The practice of self-medication is relatively common in rural villages and is often not reported to the research team.

Several factors could have explained the low performance false negativity of the OptiMAL test. Previous studies have reported a significant decrease in the sensitivity of the OptiMAL test at parasitemias < 100/μL. In addition, it has been reported that pLDH activity decreased with antimalarial therapy.23 Thus, the unreported prior use of antimalarial drugs may have resulted in remnant but non-viable pLDH-negative parasitemias. Some reports have also suggested phenotypic variations in parasites and host metabolic and/or immune factors that could reduce target antigens or interfere with their binding to detecting antibodies.10,11,24

In the opinion of all workers who participated in this study, handling of the OptiMAL test was extremely simple and rapid, making it the easiest test currently available. Although a negative OptiMAL test result indicates that a P. falciparum infection with a significant level of parasitemia is unlikely, it cannot be ruled out completely. Other limitations include cross-reactions with rheumatoid factor and the inability to provide information about the level of parasitemia. The staffs at the BHUs did not report any major problem in handling the OptiMAL test; instructions were easy to understand and follow and the results were easy to interpret. Most importantly, the test was completed in 15–20 minutes and did not require any microscopy, which the majority of the staffs at the BHUs were not comfortable with and wanted to avoid doing.

In conclusion, this study investigated the use of the non-microscopic, rapid OptiMAL test by relatively non-technical volunteer staffs at the BHUs in rural villages. The performance of the test was adequate at both the BHUs and the DHQ Center, and the results obtained correlated well with each other and with those obtained by microscopy at the DHQ Center.

These results, combined with other advantages of the OptiMAL test, such as availability of results in 10–15 minutes and relative simplicity compared with microscopy and other confirmatory tests, suggest that the OptiMAL test can be used by relatively inexperienced persons to diagnose malaria infection in rural areas where microscopic facilities are not available.

Table 1

Summary of findings in 930 suspected malaria patients for microscopy and the OptiMAL test at the Basic Health Units and the District Health Quarter Center

Basic Health UnitsDistrict Health quarter center
MicroscopyOptiMAL testMicroscopyOptiMAL test
* P. malariae and P. ovale are not included.
Plasmodium falciparum92115131114
P. vivax126144206164
Mixed13194922
Total positive231278386300
Total negative699652544630
Parasite density/μL*
<50023357236
500–5,000167198266218
>5,00041454846
Total231278386300
Table 2

Comparative performance of the OptiMAL test in 930 suspected malaria patients at the Basic Health Units and District Health Quarter Center compared with microscopy of stained blood films at the District Health Quarter Center*

OptiMAL test at Basic Health UnitsOptiMal test at District Health Quarter Center
Microscopy at District Health Quarter CenterPositiveNegativePositiveNegative
* The data on mixed infections are not included.
Plasmodium falciparum
    Positive (131)1022911120
    Negative (799)137863796
    Total (930)115815114816
P. vivax
    Positive (206)1268015650
    Negative (724)187068716
    Total (930)144786164766
Table 3

Sensitivity and specificity of the OptiMAL test for detecting malaria infection at the Basic Health Units and the District Health Quarter Center relative to microscopy at the District Health Quarter Center*

Basic Health UnitsDistrict Health Quarter Center
PfPvPfPv
* Values are percentages. Pf = Plasmodium falciparum; Pv = P. vivax; PPV = positive predictive value; NPV = negative predictive value.
Sensitivity, specificity, and positive and negative predictive values were calculated using microscopy as the standard test as described in the Patients and Methods.
Sensitivity78618576
Specificity98989999
PPV89889795
NPV96909893
Table 4

Comparison of the requirements, performance, direct costs, and technical specifications of microscopy and rapid antigen test (OptiMAL)

MicroscopyOptiMAL test
Requirements
    EquipmentMicroscopeNone
    ElectricityPreferred, not requiredNone
    StorageRoom temperatureRoom temperature
    TrainingExpert microscopistMinimal training
Performance
    Turn around timeMinimum 40–60 minutes15–20 minutes
    SubjectivityHighLow
    User acceptanceLow to mediumHigh
Costs
    Cost per testUS$ 0.10–0.40US$ 0.60–2.00
Technical specifications
    Detection threshold5–50 parasites/μL of blood50–100 parasites/μL of blood
    Detection of stagesYesNo
    QuantificationPossibleNot possible
    Sensitivity for gametocytesGoodPoor (<20%)
    Antigen persistenceNoYes
    Predictive accuracyHighLow to medium

Authors’ addresses: Jamshaid Iqbal and Nabila Khalid, Department of Microbiology, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13110, Kuwait, E-mail: iqbal@hsc.kuniv.edu.kw. Arif Muneer and Mohammed A. Ahmed, Malaria Control Department, Lahore, Punjab, Pakistan.

Acknowledgments: We thank the technical staff at the Basic Health Unit and District Health Quarter Centers for their assistance in testing specimens for malaria.

Financial support: This study was supported by a grant from Kuwait University (MI 109, MI 06/01).

REFERENCES

  • 1

    Moody A, 2002. Rapid diagnostic tests for malaria parasites. Clin Microbiol Rev 15 :66–78.

  • 2

    World Health Organization, 1999. New Perspectives: Malaria Diagnosis. Report of a Joint WHO/USAID Informal Consultation, October 25–27, 1999. Geneva. WHO/MAL/2000. 1091.

  • 3

    Beadle C, Long GW, Weiss WR, McElroy PD, Maret SM, Oloo AJ, Hoffman SL, 1994. Diagnosis of malaria by detection of Plasmodium falciparum HRP-2 antigen with a rapid dipstick antigen-capture assay. Lancet 343 :564–568.

    • Search Google Scholar
    • Export Citation
  • 4

    Durrheim DN, la Grange JJP, Govere J, Mngomezulu NM, 1998. Accuracy of a rapid immunochromatographic card test for Plasmodium falciparum in a malaria control programme in South Africa. Trans R Soc Trop Med Hyg 92 :32–33.

    • Search Google Scholar
    • Export Citation
  • 5

    Garcia M, Kirimoama S, Marlborough D, Leafasia J, Rieckmann KH, 1996. Immunochromatographic test for malaria diagnosis (letter). Lancet 347 :1549.

    • Search Google Scholar
    • Export Citation
  • 6

    Singh N, Valecha N, Sharma VP, 1997. Malaria diagnosis by field workers using an immunochromatographic test. Trans R Soc Trop Med Hyg 91 :396–397.

    • Search Google Scholar
    • Export Citation
  • 7

    Wongsrichanalai CN, Tulyayon S, Thanoosingha N, Laoboonchai A, Thaimasarn K, Brewer TG, Happner DG, 1999. Comparison of a rapid field immunochromatographic test to expert microscopy for the detection of Plasmodium falciparum asexual parasitemia in Thailand. Acta Trop 73 :263–273.

    • Search Google Scholar
    • Export Citation
  • 8

    Iqbal J, Sher A, Hira PR, Al-Owaish R, 1999. Comparison of the OptiMAL test with PCR for diagnosis of malaria in immigrants. J Clin Microbiol 39 :3644–3646.

    • Search Google Scholar
    • Export Citation
  • 9

    Iqbal J, Hira PR, Sher A, Al-Enezi AA, 2001. Diagnosis of imported malaria by Plasmodium lactate dehydrogenase (pLDH) and histidine-rich protein 2 (PfHRP-2)-based immunocapture assays. Am J Trop Med Hyg 64 :20–23.

    • Search Google Scholar
    • Export Citation
  • 10

    Moody A, Hunt-Cooke A, Gabbett E, Chiodini P, 2000. Performance of the OptiMAL malaria antigen capture dipstick for malaria diagnosis and treatment monitoring at the Hospital for Tropical Diseases, London. Br J Haematol 109 :891–894.

    • Search Google Scholar
    • Export Citation
  • 11

    Palmer CJ, Lindo JF, Klaskala WI, Quesada JA, Kaminsky R, Baum MK, Ager AL, 1998. Evaluation of the OptiMAL test for rapid diagnosis of Plasmodium vivax and Plasmodium falciparum malaria. J Clin Microbiol 36 :203–206.

    • Search Google Scholar
    • Export Citation
  • 12

    Cho-Min-Naing, Gatton ML, 2002. Performance appraisal of rapid on-site malaria diagnosis (ICT Malaria Pf/Pv test) in relation to human resources at village level in Myanmar. Acta Trop 81 :13–19.

    • Search Google Scholar
    • Export Citation
  • 13

    Dyer ME, Tjitra E, Currie BJ, Anstey NM, 2000. Failure of ‘pan malarial’ antibody of the ICT Malaria Pf/Pv immunochromatographic test to detect symptomatic Plasmodium malariae infection. Trans R Soc Trop Med Hyg 94 :518.

    • Search Google Scholar
    • Export Citation
  • 14

    Huong NM, Davis TME, Hewitt S, Huong NV, Uyen TT, Nhan DH, Cong LD, 2002. Comparison of three antigen detection methods for diagnosis and therapeutic monitoring of malaria: a field study from southern Vietnam. Trop Med Int Health 7 :304–308.

    • Search Google Scholar
    • Export Citation
  • 15

    Jelinek T, Grobusch MP, Harms G, 2001. Evaluation of a dipstick test for the rapid diagnosis of imported malaria among patients presenting within the Network TropNetEurop. Scand J Infect Dis 33 :752–754.

    • Search Google Scholar
    • Export Citation
  • 16

    Warhurst DC, Williams JE, 1996. Laboratory diagnosis of malaria: ACP Broadsheet No. 148. J Clin Pathol 49 :533–538.

  • 17

    World Health Organization, 1996. Management of Uncomplicated Malaria and the Use of Antimalarial Drugs for the Protection of Travelers. Report of an Informal Consultation. September 18–21, 1995. Geneva. WHO/MAL/96. 1075: 98.

  • 18

    Jelinek T, Grobusch MP, Nothdurft H, 2000. Use of dipstick test for the rapid diagnosis of malaria in non-immune travelers. J Travel Med 7 :175–179.

    • Search Google Scholar
    • Export Citation
  • 19

    Ferro BE, Gonzalez IJ, Carvajal F, Palma GI, Saravia NG, 2002. Performance of OptiMAL(R) in the diagnosis of Plasmodium vivax and Plasmodium falciparum infections in a malaria referral center in Colombia. Mem Inst Oswaldo Cruz 97 :731–735.

    • Search Google Scholar
    • Export Citation
  • 20

    Shiff CJ, Premji Z, Minjas JN, 1993. The rapid manual ParaSight F test: a new diagnostic tool for Plasmodium falciparum infection. Trans R Soc Trop Med Hyg 87 :646–648.

    • Search Google Scholar
    • Export Citation
  • 21

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