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Toxoplasmosis is a neglected tropical disease with a global distribution that is estimated to infect one third of the world’s human population. This study was a comparison of ELISA and rapid Immunochromatographic tests (ICT) in diagnosis of toxoplasmosis in Port Harcourt Nigeria. Eight hundred patients grouped in four categories from three Health Care Centres were randomly sampled after due ethical approval was obtained. Samples were analysed using Toxo IgG-IgM rapid test (ICT) and Enzyme linked Immunosorbent Assay (ELISA) technique. Socio Demo graphic Data were obtained using well-structured questionnaires. The seroprevalence of toxoplasmosis based on ICT was 28.1% while that of ELISA was 34.5% both significant (P < 0.05) with a relative risk of 0.815. The diagnostic parameters of ICT versus ELISA IgG were sensitively 46.7% specificity 81.7% positive predictive value (PPV) 57.3%, Negative predictive value (NPV) 74.4with a diagnostic efficiencyof 69.6%Cohen Kappas indicate good to moderate agreement between the two tests for detecting IgG. Although ELISA is the gold standard for diagnosing toxoplasmosis,ICT being less expensive, faster with high specificity and good diagnostic efficiency indetecting IgG is recommended as a preliminary screening tool for diagnosing toxoplasmosis in remote areas and facilities because ELISAislaborious, expensive and not readily available
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Abstract INTRODUCTION: Rapid diagnostic tests (RDTs) are selected based on their performances. Here, we compared the diagnostic performance of different malaria RDTs. METHODS: Febrile patients were tested for malaria using Vikia Malaria Pf/Pan, Meriline-Meriscreen Pf/Pv/Pan, Right Sign Malaria Pf/Pan, and Right Sign Malaria Pf RDTs at Melen Regional Hospital in Gabon. RESULTS: In total, 120 of 274 tested children (43.8%) had malaria. The sensitivity was > 95% for all RDTs, while the specificity was > 85% for two tests. One test generated invalid tests (8%). CONCLUSIONS: Based on their performances, all tests except one may be recommended for malaria diagnosis.
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Humans , Male , Female , Infant , Child, Preschool , Child , Reagent Kits, Diagnostic , Malaria/diagnosis , Sensitivity and Specificity , GabonABSTRACT
Background:Malaria remains a major public health threat claiming many lives particularly in Sub-Saharan Africa. Light microscopy and RDTare the mainstay tests in the clinical settings for malaria diagnosis. Many studies report varying levels of validity of these tests compared to molecular methods like PCR. Documentation on such comparative study involving the use of molecular techniques as reference test is scanty in Ghana. This study therefore assesses the diagnostic performance of these tests compared to PCR.Methods:Blood film microscopy (thin and thick), RDTand nested PCRwere run on blood samples from a total of 188 malaria suspected patients. The accuracy indices of the microscopy and RDTwere calculated using the results of the PCRas the reference test.Results:A total of 188 patients were recruited with females constituting the majority 128 (68%). The paediatric age group 1-10 years carried the largest burden of malaria by means of all the 3 tests.Asensitivity of 47.37% (95% ci, 37.03 –57.88%) was shown by both the microscopy andRDTwith specificity of 93.55% (95% ci, 86.48 –97.60) and 100% (95% ci, 96.11 –100.00%) and kappa co –efficient of 0.41 and 0.47 respectively.Conclusion:Both microscopy and RDTexhibited high level of specificity but low sensitivity. Significant number of malaria parasitaemic patients as revealed by the PCRwas missed by both the RDTand blood film microscopy and thus went undiagnosed.
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A rapid diagnostic test (RDT) kit was developed to detect non-structural protein 1 (NS1) of yellow fever virus (YFV) using monoclonal antibody. NS1 protein was purified from the cultured YFV and used to immunize mice. Monoclonal antibody to NS1 was selected and conjugated with colloidal gold to produce the YFV NS1 RDT kit. The YFV RDTs were evaluated for sensitivity and specificity using positive and negative samples of monkeys from Brazil and negative human blood samples from Korea. Among monoclonal antibodies, clones 3A11 and 3B7 proved most sensitive, and used for YFV RDT kit. Diagnostic accuracy of YFV RDT was fairly high; Sensitivity was 0.0% and specificity was 100% against Dengue viruses type 2 and 3, Zika, Chikungunya and Mayaro viruses. This YFV RDT kit could be employed as a test of choice for point-of-care diagnosis and large scale surveys of YFV infection under clinical or field conditions in endemic areas and on the globe.
Subject(s)
Animals , Humans , Mice , Antibodies, Monoclonal , Brazil , Clone Cells , Dengue Virus , Diagnosis , Diagnostic Tests, Routine , Gold Colloid , Haplorhini , Korea , Point-of-Care Systems , Sensitivity and Specificity , Yellow fever virus , Yellow FeverABSTRACT
To evaluate the implementation effect of the optimization strategy for the use and management of malaria rapid diagnostic testing (RDT) technology in Jiangsu Province, so as to provide the empirical evidence and suggestions for promoting the standardized use of RDT technology.Questionnaire surveys of primary-level health professionals’ RDT-related knowledge, attitude, and practice (KAP) and work satisfaction were conducted in 4 pilot cities in Jiangsu Province before and after the intervention.After the implementation of the intervention, 13.9% of surveyed laboratory technicians, 21.9% of surveyed clinicians and 4.1% of surveyed staff of the centers for disease control and prevention (CDCs) had significant improvements in RDT-related knowledge. About 10.9% of the surveyed laboratory technicians and 25.6% of the surveyed CDC staff improved their attitudes toward RDT technology. About 38.4% of the surveyed laboratory technicians and 10.0% of the surveyed clinicians improved the standardized use of RDT technology. All types of primary-level health professionals had high evaluation in the satisfaction and effectiveness of the optimization strategy. However, the evaluation of the surveyed clinicians was slightly lower than that of the laboratory technicians and CDC staff.The optimization strategy in this project can effectively improve the knowledge, attitude and behavior of all types of primary-level health professionals and help to promote the standardized use of RDT technology.
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To investigate the malaria rapid diagnostic testing (RDT) - related knowledge, attitude, practice (KAP) of primary healthcare professionals in Jiangsu Province and analyze the corresponding influencing factors.Four cities in Jiangsu Province were selected as the study sites by the typical sampling method to conduct a survey for the RDT related KAP and work satisfaction of primary healthcare professionals, and the multiple logistic regression model was used to explore the relevant influencing factors.Totally 1 150 questionnaires were issued and 949 valid questionnaires were collected with the recovery rate of 82.52%. The valid questionnaires included 453 questionnaires from laboratory technicians, 466 from clinicians, and 30 from malaria prevention and control workers. Totally 83.98% of the surveyed professionals had a low mastering level of essential RDT-related knowledge. A total of 52.17% of the surveyed laboratory technicians recognized that the application of RDT technology could effectively improve the current primary-level microscopy work, and the degree of recognition of RDT technological advantage in the laboratory technicians was higher than that in the clinicians. Totally 79.25% of the surveyed laboratory technicians regarded themselves to be capable of conducting the standardized RDT operation, and 84.55% of the surveyed clinicians regarded themselves to be capable of conducting the qualified malaria clinical diagnostic practice. The key influencing factors of RDT-related KAP of primary healthcare professionals included the laboratory technicians’ gender, educational level, employer’s institutional level, professional title, and working years, and the employer’s institutional level of clinicians.The primary healthcare professionals in Jiangsu Province exhibita good acceptability towards RDT technology. However, their essential knowledge on RDT remains to be improved. Therefore, it is necessary to establish a specific training and educational system for primary healthcare professionals to better guarantee the advantageous impact of RDT technology on the consolidation of the malaria elimination work achievements.
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We developed a Rapid Diagnostic Test (RDT) kit for detecting IgG/IgM antibodies against Zika virus (ZIKV) using monoclonal antibodies to the envelope (E) and non-structural protein 1 (NS1) of ZIKV. These proteins were produced using baculovirus expression vector with Sf9 cells. Monoclonal antibodies J2G7 to NS1 and J5E1 to E protein were selected and conjugated with colloidal gold to produce the Zika IgG/IgM RDT kit (Zika RDT). Comparisons with ELISA, plaque reduction neutralization test (PRNT), and PCR were done to investigate the analytical sensitivity of Zika RDT, which resulted in 100% identical results. Sensitivity and specificity of Zika RDT in a field test was determined using positive and negative samples from Brazil and Korea. The diagnostic accuracy of Zika RDT was fairly high; sensitivity and specificity for IgG was 99.0 and 99.3%, respectively, while for IgM it was 96.7 and 98.7%, respectively. Cross reaction with dengue virus was evaluated using anti-Dengue Mixed Titer Performance Panel (PVD201), in which the Zika RDT showed cross-reactions with DENV in 16.7% and 5.6% in IgG and IgM, respectively. Cross reactions were not observed with West Nile, yellow fever, and hepatitis C virus infected sera. Zika RDT kit is very simple to use, rapid to assay, and very sensitive, and highly specific. Therefore, it would serve as a choice of method for point-of-care diagnosis and large scale surveys of ZIKV infection under clinical or field conditions worldwide in endemic areas.
Subject(s)
Antibodies , Antibodies, Monoclonal , Baculoviridae , Brazil , Cross Reactions , Dengue Virus , Diagnosis , Diagnostic Tests, Routine , Enzyme-Linked Immunosorbent Assay , Flavivirus , Gold Colloid , Hepacivirus , Immunoglobulin G , Immunoglobulin M , Korea , Methods , Neutralization Tests , Point-of-Care Systems , Polymerase Chain Reaction , Reagent Kits, Diagnostic , Sensitivity and Specificity , Sf9 Cells , Yellow Fever , Zika VirusABSTRACT
Objective To compare the application effects of three methods,namely microscopic examination,antigen detec-tion(RDT)and nucleic acid test(PCR)in malaria detection between municipal and districts/counties centers for disease con-trol and prevention in Shanghai,and analyze the malaria detection ability of the laboratories in Shanghai. Methods The blood smears,whole blood samples,case review confirmation records and case data of malaria cases and suspected cases in Shanghai from 2012 to 2015 were collected by Shanghai Municipal Center for Disease Control and Prevention,and the detection results were analyzed and compared. Results A total of 212 samples with complete data were submitted by all districts(counties)in Shanghai from 2012 to 2015,the samples submitted by Jinshan Districts were the most(41.98%),and among the first diagnosis hospitals,those submitted by the tertiary hospitals were the most(82.07%). The submitted samples in the whole year were in-creased gradually from January to October. All the 212 samples were detected by three methods(the microscopic examination, RDT and PCR)in the laboratory of Shanghai Municipal Center for Disease Control and Prevention,and 167 were tested and con-firmed comprehensively as positives,accounting for 78.77%,and 45 were confirmed as negatives,accounting for 21.23%. The samples were detected by the method of microscopy and domestic RDT in the laboratories of the centers for disease control and prevention at district/county level,totally 153 were tested as positives,accounting for 72.17%,41 were unclassified,account-ing for 19.34%,53 were negative,accounting for 25.00%,and 6 were undetected,accounting for 2.83%. The coincidence of microscopic examination between the report hospitals and the centers for disease control and prevention at district/county level was 78.16%,and the coincidence between centers for disease control and prevention at district/county level and municipal level was 93.20%. The utilization rate of RDT in the laboratory of district/county level was 73.58%. The coincidence of RDT tests be-tween those domestic and imported was 93.59%. Compared with the detection results by municipal center for disease control and prevention,37 samples were misjudged by the laboratories of district/county level. Almost all(99.37%)of the confirmed malar-ia cases were imported overseas,including Africa(85.44%),Asia(13.92%)and America(0.63%). Conclusion The surveil-lance after malaria elimination in Shanghai should be carried out by combining with different detection methods and resource in-tegration.
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ELISA has been used for the diagnosis of toxoplasmosis, but it is being gradually replaced by a rapid diagnostic test (RDT). We compared and analyzed ELISA and RDT results using the sera collected during 4 consecutive years from residents of Gyodong-do (Island), Incheon-city, Korea. Sera from 921, 993, 940, and 838 adult residents were collected on a yearly basis (2010–2013). ELISA was performed by using a crude extract of T. gondii RH strain antigen and IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), GST-linker-SAG1A, were applied to the sera. Comparison between groups was analyzed by the Student’s t-test. The positive seroprevalence surged from 14.7% (135/921, 2010), 23.1% (231/993, 2011), 23.6% (222/940, 2012), and 32.1% (269/838, 2013) by ELISA. In contrast, RDT showed a more moderate increasing trend from 21.7% (200/921, 2010), 25.5% (253/993, 2011), 28.9% (272/940, 2012) and 33.1% (277/838, 2013). Discrepancies between ELISA and RDT were noted near the cut-off value. At the OD 0.15–0.24 range, RDT could detect 16.1% (169/1051) more positives, which suggests an early or acute toxoplasmosis, but at the OD 0.25–0.34 range, ELISA could detect 35.9% (92/256) more positives of possible chronic infections. Over the OD > 0.35 ELISA and RDT agreed in the majority of the cases. This surge in seroprevalence may be caused by the organic agriculture in addition to eating behavior or increase in pets among Koreans. These facts may be applied on a full-scale national survey using RDT to supplement ELISA to define the characteristics of the infection.
Subject(s)
Adult , Humans , Antigens, Surface , Diagnosis , Diagnostic Tests, Routine , Enzyme-Linked Immunosorbent Assay , Feeding Behavior , Follow-Up Studies , Korea , Organic Agriculture , Seroepidemiologic Studies , Toxoplasma , ToxoplasmosisABSTRACT
Seroprevalence of Toxoplasma gondii infection among the residents of Cheorwon-gun, Gangwon-do, Korea, which partly includes the demilitarized zone (DMZ), were surveyed for 4 years and evaluated by RDT using recombinant fragment of major surface antigen (SAG1A). Sera from 1336, 583, 526, and 583 adult residents were collected on a yearly basis from 2010 to 2013, respectively. The total positive seroprevalence was 19.3, 21.9, 23.4, and 26.8% from 2010 to 2013, respectively. The positive seroprevalence in men (23.6, 27.5, 29.5, 34.6%) was far higher than women (14.1, 18.3, 19.4, 21.4%), from 2010 to 2013, respectively. This high seroprevalence of toxoplasmosis in Cheorwon-gun may have been influenced in part by its geographical locality of the area as it includes the DMZ, where civilian access is strictly limited, thus creating a relatively isolated area that is a well-preserved habitat. Further research is necessary to study the epidemiology of toxoplasmosis in this area.
Subject(s)
Adult , Female , Humans , Male , Antigens, Surface , Ecosystem , Epidemiology , Korea , Seroepidemiologic Studies , Toxoplasma , ToxoplasmosisABSTRACT
Background: Malaria is the infectious disease causing the highest morbidity and mortality in Angola. Existing tools for the diagnosis of malaria include microscopy, rapid diagnosis tests (RDTs) and molecular tools. Nested-PCR is commonly used as a reference technique in the diagnosis of malaria due to its high sensitivity and specificity. The present study aims to evaluate the accuracy of light microscopy and SD BIOLINE Malaria Ag in the detection of Plasmodium spp. infection, using the nested-PCR as a reference method, and to determine the Plasmodium species in the study populations (Luanda, Angola) using this molecular tool. Methods: Blood samples were obtained from patients with clinical suspicion of malaria. Malaria was diagnosed by light microscopy, SD BIOLINE Malaria Ag and nested-PCR, used as a reference method, with Plasmodium falciparum, P. vivax, P. malariae, P. ovale and P. knowlesi being detected when possible. The sensitivity, specificity, positive, and negative predictive values (PPV and NPV) of microscopy and SD BIOLINE Malaria Ag were compared using the McNemar’s test and the weighted generalized score Chi-squared test for paired data. Results: A total of 225 subjects were studied. SD BIOLINE Malaria Ag was significantly more sensitive than microcopy (87.65% versus 71.60%), and was substantially correlated (κ = 0.64) with the reference method. Nested-PCR detected 36.0% (81/225) cases, 80 cases (98.8%) infected with P. falciparum and 1 case as P. malariae (1.2%), with no mixed infections. Conclusion: The findings of this study support the need to use RDT in the diagnosis of Plasmodium. PCR could appear to be a useful method for detecting Plasmodium parasites during active malaria surveillance in Angola. This study contributes to wide knowledge about the presence of Plasmodium species in Angola.
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Aim: We aimed at studying the influence of some potential interference factors on the immunochromatographic Rapid Diagnostic Tests commonly used in Cameroon for the diagnosis of Human Immunodeficiency Virus / Acquired Immune Deficiency Syndrome (HIV/AIDS) and Hepatitis B (HBV) which are major public health problems in the country. Design and Methods: The sample population of this cross-sectional study included patients referred to the BETHANIE Laboratory for the accurate diagnosis of HIV/AIDS and HBV. RDTs were performed using FIRST RESPONSE HIV Card 1-2.0 and HEXAGON HBsAg. Tests results were confirmed using a high sensitivity 3rd generation ELISA for HIV and HBV, both from FORTRESS. Assays of Rheumatoid Factors and bilirubin were conducted on HIV and HBV samples respectively. Statistical analysis was done using the R software version 3.0.2; the Chi-square test with continuity correction was applied at a threshold of 0.05. Results: A total of 25 patients were included for the HIV study group and 30 for the HBV group. Test sensitivities of 14.28% and 92.85% for FIRST RESPONSE HIV Card 1-2.0 and HEXAGON HBsAg were found respectively. Average blood levels of RF were 11.55 IU / L and 64.29 IU / L from FIRST RESPONSE HIV RDT positive and negative samples respectively. Blood levels of bilirubin were 88.63 mg / L and 131.66 mg / L from HEXAGON HBsAg RDT positive and negative samples respectively. Conclusion: HIV FIRST RESPONSE RDT results were independent (P-value = 1.00) of Rheumatoid Factor values (up to 238.8 IU / L). However, we found that HEXAGON HBsAg RDT results were not independent of bilirubin values (P-value = 0.01547), suggesting that the latter could potentially have an influence on the former.
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Malaria is a deadly disease that needs proper and prompt diagnosis in order to treat its symptoms as early as possible. Rapid diagnosis test is a pre-requisite for the effective treatment of malaria in other to reduce the mortality and morbidity of the disease especially at the Primary Health Centre (PHC) facilities. This study compares RDTs test results from PHCs with malaria Quantitative Buffy Coat (QBC) and microscopy test results. A total of 113 subjects with clinical signs of malaria were enrolled after obtaining consent of patients at the Primary Health Centres and questionnaires administered to assess awareness and use of RDTs kit. Storage and compliance to standards of usage of the Kits were observed. The results were analyzed using SPSS version 16.0. There was a significant difference (p<0.05) in sensitivity to malaria parasite between the three diagnostic methods as QBC was more sensitive compared with other diagnostic methods, while Microscopy was more sensitive compared with RDT kits. A total number of 86(76.1%), 28(24.8%) and 39(34.5%) malaria positive cases were detected by QBC, RDT and Microscopy respectively. Out of the 86(76.1%) blood samples confirmed positive by QBC, 27(31.4%) and 38(44.2%) positive cases were detectable by RDT and Microscopy respectively. Furthermore, Microcopy detected 15(53.6%) of the total positive cases detected by RDT, while RDT was able to detect 15(34.5%) of the total positive cases detected by microscopy. When compared with QBC, RDT shown a sensitivity and specificity of 32.56% (95% Cl= 22.84 – 43.52%) and 31.76% (95% Cl= 22.09% - 42.76%) respectively. On the other hand, 71.8% (95% Cl=55.12% - 84.98%) sensitivity and 87.1% (95% Cl= 78.02 – 93.35%) specificity was shown by RDT when microscopy was used as gold standard. Compliance to manufacturer’s instruction on RDT usage was poor as some of the health workers collected the blood sample directly from the pricked finger into the sample well rather than the designated capillary pipette method, while others did not comply with time before reading the results of the kits. The result from this study showed that the sensitivity and accuracy of RDTs kit is low and there is need for proper training of the health workers to avoid misuse of the kit.
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The aim of the present study was to evaluate the serological methods using ELISA with recombinant-rK39 (ELISA-rK-39) and soluble extract-SE (ELISA-SE) antigens, the indirect fluorescence antibody test (IFAT) in comparison to an immunochromatography rapid diagnostic test (RDT-rK39) and with a direct parasitological exam (PA) for Canine Visceral Leishmaniasis (CVL) diagnosis. The results showed that 89% (60/67) of the dogs were positive for at least one serological diagnostic test. ELISA-SE was the test that detected anti-Leishmania antibodies in the serum of the highest number of dogs (71.6%) followed by ELISA-rK39 (65.7%), IFAT (65.7%) and RDT-rK39 (55.2%). PA detected the lowest numbers (40.3%) of positive dogs. In relation to the total of examined dogs, the Kappa indexes (p ≤ 0.05) showed a good agreement between ELISA-SE and IFAT (88.1%; k = 0.7237), and it was also observed in the comparison of RDT-rK39 with ELISA-SE (83.6%, k= 0.6561), IFAT (83.5%, k= 0.6605) and PA (85.0%, k= 0.7074). A bad agreement was detected in any association of ELISA-rk39 with the other tests in either symptomatic or asymptomatic animals. ELISA as well as RDT using recombinant antigenic protein (rK39) were the methods that detected the lowest prevalence rates (33.3%) of CVL in asymptomatic dogs. In conclusion, only one test does not adequately identify dogs with CVL and it is necessary the association of two or more diagnostic tests. Because of the good agreement indexes of RDT-rK39 when evaluated with ELISA-SE, IFAT and PA it was suggested as a complementary method to be used in association with either ELISA-SE or IFAT, particularly in the symptomatic dogs. Furthermore, new studies are recommended in order to improve the sensitivity of tests mainly for asymptomatic dogs.
O objetivo do presente estudo foi avaliar os métodos sorológicos usando ELISA (Ensaio Imunoenzimático Indireto) com o antígeno recombinante rK39 (ELISA-rK39) e o antígeno extrato solúvel bruto (ELISA-ES) e a RIFI (Reação de Imunofluorescência Indireta) em comparação com o método imunocromatográfico rápido (RDT-rK39) e o parasitológico direto (PA), para o diagnóstico da Leishmaniose Visceral Canina (LVC) em cães de Ilha Solteira, São Paulo, Brasil. Os resultados mostraram que 89% (60/67) dos cães foram positivos por pelo menos um teste diagnóstico sorológico (RIFI, ELISA-ES, ELISA-rk39 ou RDT-rK39) e somente 40,3% (27/67) foram positivos pelo PA. O ELISA-ES foi o teste que detectou anticorpos anti-Leishmania em maior número de cães (71,6%) seguido por ELISA-rK39, RIFI (65,7%) e por RDT-rK39 (55,2%). No total de cães analisados (assintomáticos e sintomáticos), o índice Kappa de concordância (p ≤ 0,05) foi considerado de boa concordância entre ELISA-ES e IFAT (88,1%; k= 0,7237) e entre RDT-rK39 com ELISA-ES (83,6%, k= 0,6561), RIFI (83,5%, k= 0,6605) e PA (85,0%, k= 0,7074). O índice de concordância ruim foi observado em qualquer associação de ELISA-rk39 com todos os outros testes nos animais sintomáticos e nos assintomáticos. Tanto o ELISA como o RDT com proteínas recombinantes (rK39) detectaram a menor porcentagem de cães assintomáticos (33,3%) em relação aos outros testes sorológicos. Em conclusão, somente um método diagnóstico não foi suficiente para identificar todos os cães positivos com LVC, principalmente os assintomáticos e por isso foi necessário a associação de dois ou mais métodos. Em função da boa concordância do teste RDT-rK39 com ELISA-ES, RIFI e PA, o mesmo foi sugerido como um teste complementar ao ELISA-ES ou RIFI para o diagnóstico da LVC, principalmente dos cães sintomáticos. No entanto, novos estudos são recomendados para melhorar a sensibilidade dos testes principalmente para cães assintomáticos.
Subject(s)
Animals , Dogs , Dog Diseases/diagnosis , Dog Diseases/parasitology , Leishmaniasis, Visceral/veterinary , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique, Indirect , Leishmaniasis, Visceral/diagnosis , Parasitology/methodsABSTRACT
Aim: Malaria remains an enormous public health problem. Regular and ongoing surveillance to detect changes in its trends to initiate the control measures is the need of the hour. The present study was undertaken to provide the malaria transmission dynamics using surveillance indicators through active and passive surveillance in district Faridkot. Usefulness of rapid malaria diagnostic test was also evaluated. Methodology: This retrospective study extended over a period of two years (2010-2011). Thick and thin blood smears were prepared from suspected cases of malaria complaining of fever and headache for the last three days (i) of 2 CHC’s, 8 PHC’s and 68 sub centers as a part of active surveillance and (ii) those who visited GGS Medical College & Hospital and civil hospital Faridkot as a part of passive surveillance. Out of all the samples collected during the passive surveillance 995 samples collected at GGS Medical College and Hospital, Faridkot were also subjected to rapid diagnostic test (OptiMAL®). Results: The annual blood examination rate (ABER) was 9.0 and 9.7 in 2010 and 2011 respectively. Annual parasite incidence (API) recorded was < 2 (0.5) in both the years and slide positive rate (SPR) was 0.5 and 0.05 in the two respective years of study. Significant gap in the rate of case detection of active and passive surveillance systems was observed with predominance of passive surveillance. More than 96% of cases were of P. vivax. RDT’s showed an excellent correlation with conventional microscopy. Conclusion: Malaria (P. vivax) is a persistent problem in the Malwa region with variation in its transmission dynamics with in the year. P. vivax is the main species of malarial parasite in the Faridkot district with occasional cases of falciparum malaria. Prevention strategy should be targeted towards on the spot diagnosis by using RDT and hence prompt treatment. It could help to prevent spread of drug resistance and complicated malaria.
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Diagnosis of scrub typhus is difficult because its symptoms are very similar to other acute febrile illnesses, such as leptospirosis, murine typhus, and other viral hemorrhagic fevers. To differentiate scrub typhus from other acute febrile diseases, a rapid and reliable serological diagnosis is important. We have developed a chimeric recombinant antigen cr56 and two other recombinant antigens, r21 and kr56, from various serotypes of Orientia tsutsugamushi. They were tested for the detection of antibodies against O. tsutsugamushi in the patient's serum samples using enzyme-linked immunosorbent assay (ELISA) and dot-blot analyses. As of conventional immunofluorescence assay (IFA), when the mixture of these three recombinant antigens was used, both sensitivity and specificity of the recombinant antigens were increased up to 98% in IgM and IgG at ELISA and dot blotting. Additionally, both sensitivity and specificity by detection of IgM and IgG antibodies at rapid diagnostic test (RDT), using the mixture of three antigens and gold conjugated antibodies, were 99%. Our results suggest the use of mixture of these recombinant antigen proteins in ELISA or RDT is suitable as a diagnostic test for scrub typhus.
Subject(s)
Humans , Antibodies, Bacterial/blood , Antigens, Bacterial , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique, Indirect , Gold/chemistry , Immunoassay , Immunoglobulin G/blood , Immunoglobulin M/blood , Orientia tsutsugamushi/immunology , Recombinant Proteins/biosynthesis , Scrub Typhus/diagnosis , Sensitivity and Specificity , SerotypingABSTRACT
Prompt and accurate diagnosis of malaria is the key to prevent disease morbidity and mortality. This study was carried out to evaluate diagnostic performance of 3 commercial rapid detection tests (RDTs), i.e., Malaria Antigen Pf/Pantrade mark, Malaria Ag-Pftrade mark, and Malaria Ag-Pvtrade mark tests, in comparison with the microscopic and PCR methods. A total of 460 blood samples microscopically positive for Plasmodium falciparum (211 samples), P. vivax (218), mixed with P. falciparum and P. vivax (30), or P. ovale (1), and 124 samples of healthy subjects or patients with other fever-related infections, were collected. The sensitivities of Malaria Ag-Pftrade mark and Malaria Antigen Pf/Pantrade mark compared with the microscopic method for P. falciparum or P. vivax detection were 97.6% and 99.0%, or 98.6% and 99.0%, respectively. The specificities of Malaria Ag-Pftrade mark, Malaria Ag-Pvtrade mark, and Malaria Antigen Pf/Pantrade mark were 93.3%, 98.8%, and 94.4%, respectively. The sensitivities of Malaria Ag-Pftrade mark, Malaria Antigen Pf/Pantrade mark, and microscopic method, when PCR was used as a reference method for P. falciparum or P. vivax detection were 91.8%, 100%, and 96.7%, or 91.9%, 92.6%, and 97.3%, respectively. The specificities of Malaria Ag-Pftrade mark, Malaria Ag-Pvtrade mark, Malaria Antigen Pf/Pantrade mark, and microscopic method were 66.2%, 92.7%, 73.9%, and 78.2%, respectively. Results indicated that the diagnostic performances of all the commercial RDTs are satisfactory for application to malaria diagnosis.
Subject(s)
Humans , Antigens, Protozoan/blood , Cross-Sectional Studies , Diagnostic Techniques and Procedures/instrumentation , Endemic Diseases/statistics & numerical data , Malaria/diagnosis , Malaria, Vivax , Plasmodium falciparum/genetics , Reagent Kits, Diagnostic , Thailand/epidemiologyABSTRACT
Background: In 2006, the project of global fund for malaria prevention in Vietnam provided a large number of rapid diagnostic test Paracheck F for Vietnam for the purpose of rapid malaria diagnose. However, there is no study on evaluation the effect of rapid diagnostic test compared with microscopy method. Objective: To evaluate the diagnostic yield and cost of paracheck F test and microscopy in malaria diagnosis and treatment. Subject and Method: The study was carried out in 6 communes belongs to Quang Tri and Quang Binh provinces from September to November - 2006. The study was divided into 3 phases. Phase 1: diagnoses and treatments are based on clinical symptoms, phase 2: diagnoses and treatments are based on the results of paracheck and phase 3: diagnoses and treatments are based on the results of microscopy. All phases, both the common patients and malarial patients and the amount of anti-malarial drugs were treated, the amount of money was spent on transport and days work off of malarial patients and their relatives were calculated. Result: The investigation data on expenditure of malaria patients showed that: the average direct cost of malaria patient in phase 1 is VND 116.100; phase 2: VND 119.400 and phase 3: VND 120.800 per 1 treatment course. There is no significant difference between direct costs in three phases (p > 0.05). Conclusion: The expense efficiency for finding out a case of malaria by paracheck and microscopy is equivalent and lower than the expense of diagnosis based on clinical symptoms.