Non-Destructive Genotyping of Cultivars and Strains of Sesame through NIR Spectroscopy and Chemometrics.

The differentiation of cultivars is carried out by means of morphological descriptors, in addition to molecular markers. In this work, near-infrared spectroscopy (NIR) and chemometric techniques were used to develop classification models for two different commercial sesame cultivars (Sesamum indicum) and 3 different strains. The diffuse reflectance spectra were recorded in the region of 700 to 2500 nm. Based on the application of chemometric techniques: principal component analysis-PCA, hierarchical cluster analysis-HCA, k-nearest neighbor-KNN and the flexible independent modeling of class analogy-SIMCA, from the infrared spectra in the near region, it was possible to perform the genotyping of two sesame cultivars (BRS Seda and BRS Anahí), and to classify these cultivars with 3 different sesame strains, obtaining 100% accurate results. Due to the good results obtained with the implemented models, the potential of the methods for a possible realization of forensic, fast and non-destructive authentication, in intact sesame seeds was evident.

Clinical evidence for repurposing chloroquine and hydroxychloroquine as antiviral agents: a systematic review.

BACKGROUND: Repurposing hydroxychloroquine (HCQ) and chloroquine (CQ) as antiviral agents is a re-emerging topic with the advent of new viral epidemics. AIMS: To summarize evidence from human clinical studies for using HCQ or CQ as antiviral agents for any viral infection. SOURCES: PubMed, EMBASE, Scopus, Web of Science for published studies without time or language restrictions; Cochrane Clinical Trial Registry and Chinese Clinical Trials Registry for trials registered after 2015; MedRxiv for preprints within the last 12 months. CONTENT: Study eligibility criteria were interventional and prospective observational studies (with or without a control group). Participants were adults and children with a confirmed viral infection. Interventions included the use of CQ or HCQ as antiviral agent in one or more groups of the study. Two authors independently screened abstracts, and all authors agreed on eligible studies. A meta-analysis was planned if studies were available which were similar in terms of participants, intervention, comparator and outcomes. Nineteen studies (including two preprints) were eligible (HIV 8, HCV 2, dengue 2, chikungunya 1, COVID-19 6). Nine and ten studies assessed CQ and HCQ respectively. Benefits of either drug for viral load suppression in HIV are inconsistent. CQ is ineffective in curing dengue (high-certainty evidence) and may have little or no benefit in curing chikungunya (low-certainty evidence). The evidence for COVID-19 infection is rapidly evolving but at this stage we are unsure whether either CQ or HCQ has any benefit in clearing viraemia (very-low-certainty evidence). IMPLICATIONS: Using HCQ or CQ for HIV/HCV infections is now clinically irrelevant as other effective antivirals are available for viral load suppression (HIV) and cure (HCV). There is no benefit of CQ in dengue, and the same conclusion is likely for chikungunya. More evidence is needed to confirm whether either HCQ or CQ is beneficial in COVID-19 infection.

Utility of pf/pan RDT for diagnosis in the prevention of re-establishment of malaria in Sri Lanka.

The utility of CareStartTM Malaria Pf/PAN (HRP2/pLDH) Ag Combo Test, in detecting non-endemic clinical malaria cases was evaluated in Sri Lanka, a country in prevention of re-establishment of malaria following elimination. RDT, microscopy and nested PCR were performed for 350 suspected malaria patients recruited prospectively. There were 173 PCR confirmed malaria patients and 177 PCR negative subjects. Plasmodium falciparum amounted to 48% of infections with 44% P. vivax, 6% P. ovale and 2% P. malariae. Performance characteristics of RDTs and microscopy were compared with nested PCR. Sensitivity and specificity of RDT with 95% confidence intervals (CI) were as follows: any malaria infection 95.95% (CI = 91.84-98.36) and 94.92% (CI = 90.57-97.65); P. falciparum 100% (CI = 95.65-100) and 97.00% (CI = 94.18-98.70) and other species 92.22% (CI = 84.63-96.82) and 99.62% (97.88-99.99) respectively. A significant difference between sensitivities of HRP2 (100%, CI = 95.65-100) and pan pLDH line (68.67%, CI = 57.56-78.41) was seen for P. falciparum, parasite densities less than 1000 parasites/microliter being detected only by HRP2. Sensitivity and specificity of microscopy with 95% CI were as follows: any malaria infection, 94.22% (CI = 89.63-97.19) and 99.44% (CI = 96.89-99.99); P. falciparum 89.16% (CI = 80.40-94.90) and 99.63% (CI = 97.94-99.99); other species 98.89% (CI = 93.96-99.97) and 100% (CI = 98.59-100) respectively. The low sensitivity of pan specific pLDH for P. falciparum, P. ovale and P. malariae should be taken in to consideration when using this RDT as a point of care test when and wherever microscopy facilities are not readily available. Considering the low sensitivity of microscopy for P. falciparum, it is preferable to perform both tests, when malaria is highly suspected.

TGF-ß1 alters esophageal epithelial barrier function by attenuation of claudin-7 in eosinophilic esophagitis.

Barrier dysfunction has been implicated in the pathophysiology of eosinophilic esophagitis (EoE). Transforming growth factor-ß1 (TGF-ß1), a potent pleiotropic molecule, is increased in EoE; however, no study has evaluated its influence on esophageal epithelial barrier. We hypothesized that TGF-ß1 regulates barrier dysfunction in EoE. We aimed to determine the role of TGF-ß1 in the epithelial barrier in models of EoE. To examine the impact of TGF-ß1 on esophageal barrier, immortalized human esophageal epithelial (EPC2-hTERT) cells were exposed to TGF-ß1 during the three-dimensional air-liquid interface (3D-ALI) model in vitro. TGF-ß1 exposure diminished EPC2-hTERT barrier function as measured by transepithelial electrical resistance (TEER) and 3 kDa Fluorescein isothiocyanate dextran paracellular flux (FITC Flux), and hematoxylin and eosin (H&E) assessment revealed prominent cellular separation. In analysis of epithelial barrier molecules, TGF-ß1 led to the specific reduction in expression of the tight-junction molecule, claudin-7 (CLDN7), and this was prevented by TGF-ß-receptor I inhibitor. Short hairpin ribonucleic acid (shRNA)-mediated CLDN7 knockdown diminished epithelial barrier function, whereas CLDN7 overexpression resulted in protection from TGF-ß1-mediated barrier dysfunction. In pediatric EoE biopsies CLDN7 expression was decreased and altered localization was observed with immunofluorescence analysis, and the TGF-ß1 downstream transcription factor, phosphorylated SMAD2/3 (pSMAD2/3), was increased. Our data suggest that TGF-ß1 participates in esophageal epithelial barrier dysfunction through CLDN7 dysregulation.

Use of Bacillus thuringiensis israelensis in integrated vector control of Aedes sp. in Sri Lanka: a prospective controlled effectiveness study.

OBJECTIVES: The annual incidence of dengue has been increasing over the last few years in Sri Lanka with seasonal epidemics. Biological control of the vector has not been part of the integrated vector control implemented by the public health authorities of Sri Lanka so far. This pilot study assessed the effectiveness of using Bacillus thuringiensis israelensis (Bti) spray to control the Aedes mosquito vector population density. METHODS: Prospective controlled effectiveness study in three administrative divisions of Colombo. Study areas were selected from urban, semiurban and rural administrative divisions within the district, and they were compared with two matching controls from the same division. Test areas received three cycles of Bti spraying 1 month apart. Control areas were not sprayed with Bti. Ovitrap and larval indices were calculated at baseline and 2 weeks after each spray cycle. RESULTS: There was a significant improvement in the adult vector population (ovitrap index) in the test areas after three spray cycles, but this effect had disappeared after 8 weeks (no residual effect). There was no consistent positive impact on larval indices (premise, container and Breteau indices) after each spray cycle. CONCLUSION: Bti might have a moderate impact on adult vector populations mediated via transient reductions in larval populations. However, this effect is not sustained probably due to rapid re-infestation. Bti spray, if implemented, can only play a supplementary role to other vector control methods.

Amphotericin B for treatment of visceral leishmaniasis: systematic review and meta-analysis of prospective comparative clinical studies including dose-ranging studies.

OBJECTIVES: To evaluate the evidence for use of different formulations of amphotericin B (AmB), minimum effective dose for each formulation and its comparative efficacy against other drugs in achieving definitive cure of visceral leishmaniasis. METHODS: This systematic review and meta-analysis included following data sources: PubMed, Embase, Scopus, Web of Science and CINAHL. Controlled prospective clinical trials (randomized or nonrandomized, including dose-ranging studies) conducted between 1996 and 2017 with at least one treatment group receiving AmB were included (published data only). The primary outcome was definitive cure at 6 months. Adverse events and mortality were assessed as secondary outcomes. The PROSPERO registration number for this review is CRD42017067488. RESULTS: Thirty-one studies (26 from India) that enrolled 6903 patients into 84 study groups met the selection criteria. In India, liposomal AmB was not inferior to AmB deoxycholate (relative risk 1.00, 95% confidence interval (CI) 0.96-1.03, two randomized controlled trials (RCTs), 514 participants, high-quality evidence), and a single dose of the earlier formulation as low as 3.75 mg/kg achieved a cure rate of over 89% (95% CI 70.6-97.2). AmB deoxycholate was as effective as miltefosine (relative risk 0.99, 95% CI 0.95-1.03, two trials, 523 participants, high-quality evidence) and may be better than paromomycin (relative risk 1.04, 95% CI 1.02-1.07, one trial, 667 participants, low-quality evidence) in achieving definitive cure. CONCLUSIONS: AmB is an efficacious drug in the Indian subcontinent. Further evidence is needed from prospective clinical trials in other endemic geographical regions.

Imported malaria: a possible threat to the elimination of malaria from Sri Lanka?

OBJECTIVE: To discuss epidemiological aspects of imported malaria and the potential impact of imported malaria cases reported in Sri Lanka 2008-2011 in terms of a possible resurgence of the disease. METHODS: The national malaria database was used to assess details regarding country where the infection was possibly acquired, species of Plasmodium, number of days lapsed between disembarkation in Sri Lanka and diagnosis, compliance with national treatment guidelines including percentage of patients followed up as per the national guidelines. RESULTS: After the strengthening of malaria surveillance, during the 4-year period, 152 imported malaria cases were recorded: an increase of 176% in the number of cases. Most of the imported malaria infections were acquired by Sri Lankan Nationals mainly from South Asia, especially India. Plasmodium vivax accounted for 64% of the infections. Approximately 50% of the cases were diagnosed in the Western Province. The average period from disembarkation in Sri Lanka to malaria diagnosis was 3.6 days. Patients were managed and treated according to the national guidelines. 82% of the patients were followed up for 28 days to ensure parasite clearance. CONCLUSIONS: There is a possible increasing risk of re-introduction of malaria to the country from imported cases. Enhanced surveillance activities and the increase in international travel have contributed to an increase in recorded case numbers. There is a need to further strengthen surveillance, especially for monitoring and timely addressing of imported malaria, if the country is to prevent the re-establishment of transmission within. The importance of having an efficient response mechanism to deal with imported malaria is also highlighted.

A meta-analysis of magnesium for tetanus.

Uncontrolled studies suggest that magnesium sulphate controls spasms in patients with established tetanus. We performed a meta-analysis of controlled trials that compared magnesium sulphate with placebo or diazepam for the treatment of patients with tetanus. We searched PubMed, Scopus, Embase and the Cochrane clinical trials registry. Three studies met the inclusion criteria, containing 275 participants (199 male patients, 72.4%). Magnesium sulphate did not reduce mortality, relative risk (95% CI): vs placebo, 0.80 (0.41-1.58); vs diazepam, 1.11 (0.70-1.75). The data on duration of total intensive care unit stay, total hospital stay and the need for ventilatory support were conflicting and pooling of results could not be done due to methodological differences of individual trials. More controlled trials are needed to assess the effect of magnesium sulphate on reducing autonomic instability, spasms, duration of intensive care and hospital stays and the need for mechanical ventilation.

Diagnosis and treatment of malaria by health care providers: findings from a post conflict district in Sri Lanka.

This study determines whether 72 health care providers in a previously conflict-affected district in Sri Lanka adhere to the recommendations of the Anti Malaria Campaign with regard to diagnosis, prescribing antimalarials and reporting of a positive case. All patients suspected of clinically having malaria are being referred for laboratory confirmation, indicating that presumptive treatment is not practiced. The knowledge amongst health care providers regarding accurate management and reporting of a malaria positive case needs to be improved.

Candidate gene study of susceptibility to cutaneous leishmaniasis in Sri Lanka.

OBJECTIVES: To investigate the association between selected single nucleotide polymorphisms (SNPs) in TNF, LTA and SLC11A1 genes and risk of endemic cutaneous leishmaniasis (CL) in Sri Lanka through a case-control disease association study. METHODS: An anonymized DNA resource representative of the Sri Lankan population was genotyped initially to establish baseline parameters. This was followed up by genotyping 200 patients and 200 matched controls. Published or modified PCR/RFLP methods were employed for genotyping. RESULTS: Comparison of the different ethnic groups showed the distribution of alleles of LTA +252 A>G to differ significantly in Tamils and Moors when compared with Sinhalese. The differences seen at allele level were also reflected in the haplotypes defined by these SNPs at the TNF locus. The case-control analysis did not show an association between the SNPs or the haplotypes investigated and CL. The distribution of these variant alleles in other populations, where they are positively associated with leishmaniasis, differed significantly from the Sri Lankan study cohort. CONCLUSIONS: The selected polymorphisms do not predispose to CL in the Sri Lankan population. The study of extended haplotypes at these loci using a sufficiently powered sample collection would elaborate the findings of this study. In the face of an evolving disease pattern in the country with other forms of leishmaniasis now being reported, prevalence of polymorphisms predisposing to these forms calls for heightened surveillance and preparedness.

Some sociological aspects of cutaneous leishmaniasis in patients attending a tertiary referral centre in Colombo, Sri Lanka.

Over 1800 clinically suspected cases of cutaneous leishmaniasis have been referred to the Department of Parasitology, Faculty of Medicine, Colombo, Sri Lanka for investigation since 2001. This study analyses some sociological aspects of 120 patients with laboratory confirmed cutaneous leishmaniasis. This information is important to design and implement control programmes. The disease was predominant among males. In females lesions occurred mainly on the face, while in men they were seen mainly on the limbs. Immediate medical advice was sought by 13% of the population; the others sought treatment when the skin lesion grew or failed to heal. Females delayed seeking treatment as they probably misinterpreted the lesion as a pimple. Only 39% were referred to a Consultant Dermatologist by a medical officer during the first visit. The mean duration of time from the detection of the lesion to referral was approximately eight months. Psychologically, the presence of the lesion affected less than 20% of individuals. Costs related to treatment were relatively low in Sri Lanka. Late presentation and diagnostic delay was related to lack of awareness. Educational programmes should be carried out, aimed both at health care workers and the community to ensure early diagnosis and treatment for cutaneous leishmaniasis.

Sleeping arrangements under long-lasting impregnated mosquito nets: differences during low and high malaria transmission seasons.

Sleeping arrangements under long-lasting impregnated nets (LLIN) were recorded in 2467 households during the low malaria transmission season (May-June 2007) and the same families were followed up during the high malaria transmission season (December 2007-January 2008) in two malaria-endemic areas of Sri Lanka. Approximately 800 households each from the three main ethnic groups were studied. The number of families lost to follow-up was 68. A significant increase was seen in the proportion of households using LLINs the previous night during the high transmission season (96%) compared with the low transmission season (90%) (P< or =0.001 for all three ethnic groups). When sleeping arrangements of the entire population were considered, priority to sleep under the LLIN was given to children under 5 years during both seasons. The percentage of children under five who slept under a LLIN increased from 75% during the low transmission season to 90% during the high transmission season. Utilisation of LLINs by pregnant women was low; only approximately 45% of pregnant women reported sleeping under a LLIN during both seasons. The study suggests the possible need for re-focusing of health education messages regarding the importance of LLIN use among pregnant women.

Community factors affecting long-lasting impregnated mosquito net use for malaria control in Sri Lanka.

The Anti Malaria Campaign distributed approximately 300,000 long-lasting impregnated nets (LLINs) to malaria-endemic areas in Sri Lanka during the years 2005 to 2007. We conducted a community-based cross-sectional survey among 2467 households distributed among the three major ethnic groups of Sri Lanka to study the perceptions and practices with regard to the use of LLINs in order to improve their use. In a majority of households the number of LLINs available was not sufficient for the number of people, although there was a small percentage of households that had excess nets. The information and advice given at the time of distribution regarding use of the nets differed amongst the three groups and was not consistent. Dissemination of this knowledge within the family was not observed. A relationship between knowledge regarding LLINs and reported practices on washing and drying of LLINs was found. It was noted that net shape may influence net use, with cone shaped nets being more popular. Efforts to increase knowledge on LLINs using behaviour change communication techniques would have more effectively contributed to achieve planned outcomes. Proper use of LLINs will undoubtedly contribute to further reduction of malaria in Sri Lanka.

Clinical manifestations of cutaneous leishmaniasis in Sri Lanka - possible evidence for genetic susceptibility among the Sinhalese.

Human cutaneous leishmaniasis (CL) caused by Leishmania donovani, a pathogen more usually associated with visceral leishmaniasis, is now endemic in Sri Lanka. This report details the characteristics of 200 patients with locally acquired CL, who were recruited prospectively for an ongoing study into the genetic susceptibility to CL in Sri Lanka. In each case, the CL was confirmed by the demonstration of amastigotes in a direct smear and/or promastigotes in a culture. Although only 82% of the Sri Lankan population is Sinhalese, all 200 patients belonged to this ethnic group. The patients had a median age of 32 years (range=4-80 years). Most of them each had a single, non-tender, non-itching and dry lesion which had started as a papule and then gradually enlarged and ulcerated, with changes in the surrounding skin. None of the patients had any signs of systemic disease. Eleven (5.5%) each had at least one other affected family member. Patients with multiple lesions were most likely to be found in families with more than one affected member (P=0.002) but multiple lesions were not associated with diabetes mellitus (P>0.05). Although the results of passive detection under-estimate the true occurrence of a disease, the present data point towards enhanced susceptibility to CL among the Sinhalese and/or certain individuals, possibly determined by genetic factors.

Anthelmintic prescribing patterns of a sample of general practitioners from selected areas in the colombo district of sri lanka.

General Practitioners (GPs) provide first contact care of children and pregnant mothers in the community. This study ascertained the prescribing pattern of anthelmintics to children and pregnant women by a sample of GPs from the district of Colombo. Two hundred medical practitioners engaged in full-time General Practice (100 urban and 100 rural), were selected randomly. A pre-tested interviewer-administered questionnaire was used to collect data. A total of 183 GPs aged between 26 and 72 years (median 38) participated with 94 coming from urban areas. Seventy percent of the GPs were male. Almost 13% of GPs from urban areas had a Postgraduate degree in comparison to 4.5% from the rural areas (P < 0.05). Over 50% of GPs had 6-20 years of service and over 30% treated 16-30 patients daily. Seventy-three percent of GPs from rural areas accessed health-related reading material either daily or weekly in contrast to only 40% from urban areas (P < 0.001). All GPs prescribed anthelmintics to children. Pyrantel pamoate was the preferred anthelmintic used for children by both groups. Approximately 55% and 64% of GPs from urban and rural areas, respectively, prescribed anthelmintics during pregnancy. A majority of GPs prescribed drugs after the first trimester. However, 25% from urban areas gave drugs during any trimester (P < 0.001). Regression analysis revealed that GPs with postgraduate qualifications, those having frequent access to health-related material and those seeing more than 30 patients daily, prescribed anthelmintics to pregnant women more often. Although routine de-worming of pregnant women and children should occur through government antenatal and well-baby clinics, and through the schools de-worming programme, it may not happen due to various reasons. Thus, GPs play a vital role in achieving good coverage of anthelmintics among children and pregnant women. Making available clear national guidelines on prescribing anthelmintics in Sri Lanka would improve the prescribing patterns of anthelmintics among GPs.

Epidemiological aspects and risk factors of toxocariasis in a pediatric population in Sri Lanka.

This cross-sectional study, carried out over a period of 11 months, investigated the relationship between Toxocara seropositivity, socio-demographic and environmental variables in a pediatric population. Risk factors for Toxocara infection were assessed by direct interview of parent or guardian using a structured pre-tested questionnaire. Eosinophilia and presence of helminth eggs or protozoan cysts in a fecal smear were recorded. Diagnosis of Toxocara seropositivity in children was based on IgG Toxocara Microwell Serum Elisa Kits. The ELISA test was regarded as positive if the optical density was 0.3 units or above. Unadjusted and adjusted odds ratios were calculated to determine risk factors for disease. The proportion of children who were positive for Toxocara antibodies in the study population was 20%. Children being exposed to a puppy of less than 3 months at home, visiting a playground frequently, living in a poorly constructed house and dogs having access to playgrounds were significant risk factors on univariate analysis. Of these four variables, only the first three variables (OR 19, OR 4 and OR 3, respectively) remained significant risk factors on the multivariate model. Presence of eosinophilia in seropositive children was significantly higher than the seronegative group (77% vs 40%; p < 0.001). This study indicates that dogs contribute significantly to children being seropositive for toxocariasis in Sri Lanka. Implementation of public health programs specifically focused on anti-parasitic treatment of dogs is recommended.

Reductive nitrosylation of water-soluble iron porphyrins by S-nitroso-N-acetylpenicillamine: rate constants and EPR characterization.

Reductive nitrosylation of the water-soluble iron derivatives of the cationic Fe(III)(TMPyP) and anionic Fe(III)(TPPS) porphyrins [where TMPyP=tetra-meso-(4-N-methylpyridiniumyl)porphinate and TPPS=tetra-meso-(4-sulfonatophenyl)porphinate] by the nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP) was studied using optical absorption spectroscopy and electron paramagnetic resonance. Nitrosylation rates were obtained, the reaction was found to be first order in the SNAP concentration and the stoichiometry of the reaction was one to one. The similarity between the obtained second-order rate constants for both porphyrins, k(TMPyP)=0.84 x 10(3)M(-1)s(-1) and k(TPPS)=0.97 x 10(3)M(-1)s(-1), suggested that the reaction mechanism is approximately independent of the nature of the porphyrin meso-substituents. A mechanism was proposed involving the hydrolysis of SNAP by an out of plane liganded H(2)O yielding the sulfenic acid of N-acetylpenicillamine and the transfer of NO(-) to Fe(III). The EPR (electron paramagnetic resonance) spectra of the SNAP- and gaseous NO-treated porphyrins were obtained and compared. The difference between the spectra of the cationic and anionic porphyrins indicates different local symmetry and Fe-N-O bond angle. SNAP-treatment produced much more resolved hyperfine structures than gaseous NO-treatment.

Evaluation of a rapid whole blood immunochromatographic assay for the diagnosis of Plasmodium falciparum and Plasmodium vivax malaria.

OBJECTIVE: Microscopic examination of blood smears is the 'gold standard' for malaria diagnosis, but is labour intensive and requires skilled operators. Plasmodium vivax malaria accounts for up to 70% of infections in Sri Lanka. The objective of this study was to determine the effectiveness of an immunochromatographic test which can detect both the species of Plasmodium, P. vivax and P. falciparum, present in Sri Lanka. DESIGN: Prospective study from May 2001 to March 2002. SETTING AND METHODS: All persons above 5 years of age who presented to the Malaria Research Station, Kataragama or the Anti-malaria Clinic, Kurunegala, with a history of fever were recruited to the study. Thick and thin blood smears were examined for malarial parasites. The rapid diagnostic test (RDT), ICT Malaria P.f/P.v (AMRAD ICT, Australia) was performed simultaneously by an independent investigator. The severity of clinical disease of all patients was evaluated. RESULTS: The study sample comprised 328 individuals of whom 126 (38%) were infected, 102 with P. vivax (31.1%) and 24 with P. falciparum (7.3%). The RDT was found to be highly sensitive (100%) and specific (100%) for the diagnosis of P. falciparum when compared with field microscopy. The sensitivity for the diagnosis of P. vivax malaria was only 70%. When P. vivax parasitaemia was greater than 5000 parasites/microL the RDT was 96.2% sensitive. A significant association was noted between the band intensity on the dipstick and both peripheral blood parasitaemia (p < 0.001) and clinical severity of disease with P. vivax (p = 0.011). CONCLUSIONS: The ICT Malaria P.f/P.v test can be used in Sri Lanka in the absence of microscopists.

A cost analysis of the use of the rapid, whole-blood, immunochromatographic P.f/P.v assay for the diagnosis of Plasmodium vivax malaria in a rural area of Sri Lanka.

Between May 2001 and March 2002, a prospective study was conducted in a malaria-endemic area of Sri Lanka, to determine the cost implications of using the immunochromatographic P.f/P.v test to detect Plasmodium vivax infection. All consecutive subjects aged >5 years who presented with a history of fever were recruited. Each was checked for P. vivax infection by the standard microscopical examination of bloodsmears and by the immunochromatographic test (ICT). The costs of diagnosis using each method and the sensitivity, specificity and predictive values of the ICT (with bloodsmear examination used as the 'gold standard') were estimated, the costs/case detected being simulated for different slide positivity 'rates' and ICT sensitivities. In the detection of P. vivax, the ICT had a sensitivity of 70% and a specificity of 99%. The costs of the ICT per subject investigated and per case detected were, respectively, approximately 14 and 20 times more than those of bloodsmear examination. The costs of the ICT per case detected would fall as the sensitivity of the test increased. The ICT gave relatively few false-positive results. The current, relatively high cost of the ICT is the most important barrier to its routine operational use in the diagnosis of malaria. The test is already useful, however, in specific situations.