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Tropical Medicine and Infectious Disease Mar 2023We propose a protocol suitable for point-of-care diagnosis of malaria utilizing a simple and purification-free DNA extraction method with the combination of...
We propose a protocol suitable for point-of-care diagnosis of malaria utilizing a simple and purification-free DNA extraction method with the combination of loop-mediated isothermal amplification assay and lateral flow (LAMP-LF). The multiplex LAMP-LF platform developed here can simultaneously detect and genus (for and ). Through the capillary effect, the results can be observed by the red band signal on the test and control lines within 5 min. The developed multiplex LAMP-LF was tested with 86 clinical blood samples on-site at Hospital Kapit, Sarawak, Malaysia. By using microscopy as the reference method, the multiplex LAMP-LF showed 100% sensitivity (95% confidence interval (CI): 91.4 to 100.00%) and 97.8% specificity (95% CI: 88.2% to 99.9%). The high sensitivity and specificity of multiplex LAMP-LF make it ideal for use as a point-of-care diagnostic tool. The simple and purification-free DNA extraction protocol can be employed as an alternative DNA extraction method for malaria diagnosis in resource-limited settings. By combining the simple DNA extraction protocol and multiplex LAMP-LF approach, we aim to develop a simple-to-handle and easy-to-read molecular diagnostic tool for malaria in both laboratory and on-site settings.
PubMed: 37104326
DOI: 10.3390/tropicalmed8040199 -
Cureus Mar 2023Malaria is a life-threatening parasitic disease caused by various forms of the protozoa and is transmitted by the female mosquito. The parasitic infection is endemic... (Review)
Review
Malaria is a life-threatening parasitic disease caused by various forms of the protozoa and is transmitted by the female mosquito. The parasitic infection is endemic in 90 countries, with approximately 500 million cases reported annually and an estimated annual mortality of 1.5-2.7 million individuals. Historically, the use of antimalarial drugs has been promising for the chemoprophylaxis and treatment of malaria, mitigating the annual mortality rate. Notably, these antimalarial drugs have been associated with various adverse effects, including gastrointestinal upset and headaches. However, the adverse cutaneous manifestations these antimalarial drugs may lead to are poorly documented and understood. We aim to describe the lesser-studied adverse cutaneous pathologies of malaria treatment to better educate physicians on the proper treatment of their patients. Our narrative review describes the skin manifestations associated with specific antimalarial treatments and their associated prognoses and treatments. The cutaneous pathologies discussed include aquagenic pruritus (AP), palmoplantar exfoliation, Steven-Johnson syndrome, toxic epidermal necrolysis, cutaneous vasculitis, psoriasis, ecchymosis, and tropical lichenoid dermatitis. Further studies and vigilant documentation of the cutaneous adverse events of antimalarial drugs need to be performed and emphasized to prevent potential life-threatening adverse outcomes.
PubMed: 37065311
DOI: 10.7759/cureus.36066 -
Journal of Travel Medicine May 2023Identifying the causes of Acute Undifferentiated Febrile Illness (AUFI) is key to improve the management of returning travellers with fever. We evaluated a...
BACKGROUND
Identifying the causes of Acute Undifferentiated Febrile Illness (AUFI) is key to improve the management of returning travellers with fever. We evaluated a BioFire®FilmArray® prototype panel of multiplex nucleic acid amplification tests (NAAT) targeting different relevant pathogens in travellers returning with fever.
METHODS
Prospective, multicentre study to evaluate a prototype panel in whole blood samples of adult international travellers presenting with AUFI in three European travel Clinics/Hospitals (November 2017-November 2019). We evaluated 15 target analytes: Plasmodium spp., Plasmodium falciparum, Plasmodium knowlesi, Plasmodium malariae, Plasmodium ovale, Plasmodium vivax, chikungunya virus, dengue virus, Zika virus, Anaplasma phagocytophilum, Borrelia spp., Leptospira spp., Orientia tsutsugamushi, Rickettsia spp. and Salmonella spp. Results were compared with composite reference standards (CRSs) for each target infection, including direct methods [smear microscopy, rapid diagnostic test (RDT), reference NAAT and blood cultures] and indirect methods (paired serology).
FINDINGS
Among 455 travellers with AUFI, 229 target infections were diagnosed; the prototype panel detected 143 (overall sensitivity and specificity of 62.5 and 99.8%, respectively). The panel identified all Plasmodium infections (n = 82). Sensitivity for dengue (n = 71) was 92.9, 80.8 and 68.5% compared with RDT, NAAT and CRS, respectively. Compared with direct methods and CRS, respectively, the prototype panel detected 4/4 and 4/6 chikungunya, 2/2 and 4/29 Leptospira spp., 1/1 and 1/6 O. tsutsugamushi and 2/2 and 2/55 Rickettsia spp., but 0/2 and 0/10 Zika, 0/1 and 0/11 A. phagocytophylum and 0/3 Borrelia spp. diagnosed by serology and only 1/7 Salmonella spp. diagnosed by blood cultures. 77/86 (89.5%) infections not detected by the panel were diagnosed by serology.
INTERPRETATION
The prototype panel allowed rapid and reliable diagnosis for malaria, dengue and chikungunya. Further improvements are needed to improve its sensitivity for Zika and important travel-related bacterial infections.
Topics: Adult; Humans; Chikungunya Fever; Travel; Prospective Studies; Travel-Related Illness; Malaria; Fever; Rickettsia; Multiplex Polymerase Chain Reaction; Dengue; Zika Virus; Zika Virus Infection
PubMed: 36988415
DOI: 10.1093/jtm/taad041 -
Zhongguo Xue Xi Chong Bing Fang Zhi Za... Mar 2023To establish a fluorescent assay for rapid detection of based on recombinaseaided amplification (RAA) and CRISPR-Cas12a system,and to preliminarily evaluate the...
OBJECTIVE
To establish a fluorescent assay for rapid detection of based on recombinaseaided amplification (RAA) and CRISPR-Cas12a system,and to preliminarily evaluate the diagnostic efficiency of this system.
METHODS
The ribosomal RNA () gene of was selected as the target sequence, and three pairs of RAA primers and CRISPR-derived RNA (crRNA) were designed and synthesized. The optimal combination of RAA primers and crRNA was screened and the reaction conditions of the system were optimized to create a fluorescent RAA/CRISPR-Cas12a system. The plasmid containing gene of the strain 3D7 was generated, and diluted into concentrations of 1 000, 100, 10, 1 copy/μL for the fluorescent RAA/CRISPR-Cas12a assay, and its sensitivity was evaluated. The genomic DNA from , , , hepatitis B virus, human immunodeficiency virus and was employed as templates for the fluorescent RAA/CRISPR-Cas12a assay, and its specificity was evaluated. Fifty malaria clinical samples were subjected to the fluorescent RAA/CRISPR-Cas12a assay and nested PCR assay, and the consistency between two assays was compared. In addition, strain 3D7 was cultured . Then, the culture was diluted into blood samples with parasite densities of 1 000, 500, 200, 50, 10 parasites/μL with healthy volunteers' O-positive red blood cells for the RAA/CRISPR-Cas12a assay, and the detection efficiency was tested.
RESULTS
The Pf-F3/Pf-R3/crRNA2 combination, 2.5 μL as the addition amount of B buffer, 40 min as the RAA reaction time, 37 °C as the reaction temperature of the CRISPR-Cas12a system were employed to establish the fluorescent RAA/CRISPR-Cas12a system. Such a system was effective to detect the plasmid containing gene of the strain 3D7 at a concentration of 1 copy/μL, and presented fluorescent signals for detection of , but failed to detect , , , , hepatitis B virus or human immunodeficiency virus. The fluorescent RAA/CRISPR-Cas12a system and nested PCR assay showed completely consistent results for detection of 50 malaria clinical samples ( = 1.0, < 0.001). Following 6-day culture of the strain 3D7, 10 mL cultures were generated and the fluorescent RAA/CRISPR-Cas12a system showed the minimal detection limit of 50 parasites/μL.
CONCLUSIONS
The fluorescent RAA/CRISPR-Cas12a system is rapid, sensitive and specific for detection of , which shows promising value for rapid detection and risk monitoring of .
Topics: Humans; Plasmodium falciparum; Sensitivity and Specificity; Nucleic Acid Amplification Techniques; Recombinases; CRISPR-Cas Systems; Malaria, Falciparum; Malaria; DNA Primers; Malaria, Vivax; RNA, Ribosomal, 18S
PubMed: 36974013
DOI: 10.16250/j.32.1374.2022240 -
Nature Communications Mar 2023Plasmodium falciparum (Pf) is the dominant malaria parasite in Nigeria though P. vivax (Pv), P. ovale (Po), and P. malariae (Pm) are also endemic. Blood samples...
Plasmodium falciparum (Pf) is the dominant malaria parasite in Nigeria though P. vivax (Pv), P. ovale (Po), and P. malariae (Pm) are also endemic. Blood samples (n = 31,234) were collected from children aged 0-14 years during a 2018 nationwide HIV survey and assayed for Plasmodium antigenemia, Plasmodium DNA, and IgG against Plasmodium MSP1-19 antigens. Of all children, 6.6% were estimated to have Pm infection and 1.4% Po infection with no Pv infections detected. The highest household wealth quintile was strongly protective against infection with Pm (aOR: 0.11, 95% CI: 0.05-0.22) or Po (aOR= 0.01, 0.00-0.10). Overall Pm seroprevalence was 34.2% (95% CI: 33.3-35.2) with lower estimates for Po (12.1%, 11.6-12.5) and Pv (6.3%, 6.0-6.7). Pm seropositivity was detected throughout the country with several local government areas showing >50% seroprevalence. Serological and DNA indicators show widespread exposure of Nigerian children to Pm with lower rates to Po and Pv.
Topics: Humans; Child; Seroepidemiologic Studies; Nigeria; Plasmodium; Malaria; Malaria, Vivax; Plasmodium falciparum; Antigens, Protozoan; Immunoglobulin G; Malaria, Falciparum; Plasmodium vivax
PubMed: 36914649
DOI: 10.1038/s41467-023-37010-0 -
Parasitology Research Apr 2023The global spread of multi-drug resistant P. falciparum, P. vivax, and P. malariae strains and absence of long-term effective vaccine makes chemotherapy the mainstay of...
The global spread of multi-drug resistant P. falciparum, P. vivax, and P. malariae strains and absence of long-term effective vaccine makes chemotherapy the mainstay of malaria control strategies in endemic settings. The Mossman's assay and the Organization for Economic Co-operation and Development (OECD), 2001 guideline 423, were used to determine the cytotoxicity and acute oral toxicity of a novel hybrid drug, artesunate-3-Chloro-4(4-chlorophenoxy) aniline (ATSA), in vitro and in vivo, respectively. A modified Desjardins method was used to screen for antiplasmodial activity using P. falciparum (3D and W) strains in vitro. The Peter's 4-day suppressive tests (4DTs) was used to evaluate the in vivo antimalaria activity using P. berghei ANKA strain, lumefantrine resistant (LuR), and piperaquine resistant (PQR) P. berghei lines. In silico prediction of absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles was assayed using PreADMET online prediction tool. The reference drug in all experiments was artesunate (ATS). Statistical significance between ATSA's activities in treated and control mice was evaluated by one-way analysis of variance (ANOVA). Results show that inhibitory concentrations-50 (IC) of ATSA is 11.47 ± 1.3 (3D) and 1.45 ± 0.26 (W) against 4.66 ± 0.93 (3D) and 0.60 ± 0.15 (W) ng/ml of ATS with a selective index of 2180.91(3D) and a therapeutic index (TI) of > 71). No mortalities were observed in acute oral toxicity assays and mean weight differences for test and controls were statistically insignificant (P > 0.05). The in vivo activity of ATSA was above 40% with effective dosage-50 (ED) of 4.211, 2.601, and 3.875 mg/kg body weight against P. berghei ANKA, LuR, and PQR lines, respectively. The difference between treated and control mice was statistically significant (P < 0.05). ATSA has high intestinal absorption (HIA) > 95% and has medium human ether-a-go-go related gene (hERG) K channel inhibition risks. Preclinical and clinical studies on ATSA are recommended to evaluate its value in developing novel drugs for future management of multi-drug resistant malaria parasites.
Topics: Humans; Animals; Mice; Antimalarials; Artesunate; Plasmodium falciparum; Malaria; Malaria, Falciparum; Malaria, Vivax; Lumefantrine; Aniline Compounds; Plasmodium berghei
PubMed: 36859621
DOI: 10.1007/s00436-023-07801-x -
Frontiers in Veterinary Science 2023The imminent risk of zoonoses of non-human malaria parasites is not far from reality in India, as has been observed in the case of Plasmodium knowlesi (Pk), and so is...
INTRODUCTION
The imminent risk of zoonoses of non-human malaria parasites is not far from reality in India, as has been observed in the case of Plasmodium knowlesi (Pk), and so is possible with (Pc), already reported from South East Asian countries. Therefore, a novel multiplex qPCR assay was developed and evaluated for detection of non-human malaria parasites- Pk and Pc in populations at risk.
METHODS
The qPCR primers were designed in-house with fluorescence labeled probes (HEX for Pk and FAM for Pc). DNA samples of Pk and Pc were used as templates and further the qPCR assay was evaluated in 250 symptomatic and asymptomatic suspected human blood samples from malaria endemic areas of North Eastern states of India.
RESULTS
The qPCR assay successfully amplified the target 18S rRNA gene segment from Pk and Pc and was highly specific for Pk and Pc parasites only, as no cross reactivity was observed with (Pf), (Pv), (Pm), and (Po). Standard curves were generated to estimate the limit of detection (LOD) of Pk and Pc parasites DNA (0.00275 & 0.075 ng/μl, respectively). Due to COVID-19 pandemic situation during 2020-21, the sample accessibility was difficult, however, we managed to collect 250 samples. The samples were tested for Pf and Pv using conventional PCR- 14 Pf and 11 Pv infections were observed, but no Pk and Pc infections were detected. For Pk infections, previously reported conventional PCR was also performed, but no Pk infection was detected.
DISCUSSION
The multiplex qPCR assay was observed to be robust, quick, cost-effective and highly sensitive as compared to the currently available conventional PCR methods. Further validation of the multiplex qPCR assay in field setting is desirable, especially from the high-risk populations. We anticipate that the multiplex qPCR assay would prove to be a useful tool in mass screening and surveillance programs for detection of non-human malaria parasites toward the control and elimination of malaria from India by 2030.
PubMed: 36777671
DOI: 10.3389/fvets.2023.1127273 -
Scientific Reports Jan 2023With global progress towards malaria reduction stalling, further analysis of epidemiology is required, particularly in countries with the highest burden. National...
With global progress towards malaria reduction stalling, further analysis of epidemiology is required, particularly in countries with the highest burden. National surveys have mostly analysed infection prevalence, while large-scale data on parasite density and different developmental forms rarely available. In Nigeria, the country with the largest burden globally, blood slide microscopy of children up to 5 years of age was conducted in the 2018 National Demographic and Health Survey, and parasite prevalence previously reported. In the current study, malaria parasite density measurements are reported and analysed for 7783 of the children sampled across the 36 states within the six geopolitical zones of the country. Asexual and sexual stages, and infections with different malaria parasite species are analysed. Across all states of Nigeria, there was a positive correlation between mean asexual parasite density within infected individuals and prevalence of infection in the community (Spearman's rho = 0.39, P = 0.02). Asexual parasite densities were highest in the northern geopolitical zones (geometric means > 2000 μL), extending the evidence of exceptionally high infection burden in many areas. Sexual parasite prevalence in each state was highly correlated with asexual parasite prevalence (Spearman's rho = 0.70, P < 0.001), although sexual parasite densities were low (geometric means < 100 μL in all zones). Infants had lower parasite densities than children above 1 year of age, but there were no differences between male and female children. Most infections were of P. falciparum, which had higher asexual densities but lower sexual parasite densities than P. malariae or P. ovale mono-infections. However, mixed species infections had the highest asexual parasite densities. It is recommended that future large surveys in high burden countries measure parasite densities as well as developmental stages and species, to improve the quality of malaria epidemiology and tracking of future changes.
Topics: Child; Infant; Animals; Humans; Male; Female; Parasites; Microscopy; Nigeria; Malaria; Malaria, Falciparum; Prevalence; Coinfection; Plasmodium falciparum
PubMed: 36709336
DOI: 10.1038/s41598-023-27535-1 -
Parasites & Vectors Jan 2023Malaria control efforts are highly skewed towards Plasmodium falciparum while overlooking other Plasmodium species such as P. malariae. A better understanding of the...
BACKGROUND
Malaria control efforts are highly skewed towards Plasmodium falciparum while overlooking other Plasmodium species such as P. malariae. A better understanding of the role of Plasmodium species other than P. falciparum is needed to strengthen malaria elimination initiatives. The aim of the present study was to elucidate the contribution of P. malariae to malaria transmission in Cameroon.
METHODS
The study was conducted in the Ngatti Health District, a forest-savannah transition area in the Adamawa Region, Cameroon. A total of 497 individuals aged from 1 to 85 years were diagnosed with malaria in November 2020 using a rapid diagnostic test (RDT) and microscopy. Adult mosquitoes were collected between September 2019 and March 2020 by indoor aspiration and identified morphologically and molecularly. The infection status of Plasmodium spp. was also determined by quantitative PCR, and dried blood spots were collected from 156 participants with the aim to detect different Plasmodium species by nested PCR.
RESULTS
The overall Plasmodium prevalence was 50.3%, 51.8% and 64.7%, as detected by microscopy, the RDT and PCR, respectively. Based on the PCR results, P. falciparum was the most prevalent species (43%); followed by co-infections P. falciparum/P. malariae (17%), P. falciparum/P. ovale (1.3%), P. falciparum/P. ovale/P. malariae (1.3%); and then by P. malariae mono-infection (2.5%). The same trend was observed using microscopy, with 35% of participants infected with P. falciparum, 11% co-infected with P. falciparum/P. malariae and 4% infected with P. malariae. The prevalence and parasite density of malaria infection varied significantly with age group (P < 0.05), with the highest prevalence rate observed in children aged 6-10 years (P = 0.0001) while the density of Plasmodium infection increased significantly in children aged < 5 years compared to the other age groups (P = 10). Among the 757 Anopheles mosquitoes collected, 737 (97.35%) were An. funestus sensu stricto, 15 (1.9%) were An. gambiae and 5 (0.6%) were An. hancocki. The Plasmodium species recorded at the head/thorax level were P. falciparum and P. malariae, with a sporozoite infection rate of 8.4%; the highest sporozoite infection rate was recorded at Mibellon village (13.6%).
CONCLUSION
The results of this study reveal the significant contribution of P. malariae, in addition to P. falciparum, to the high malaria transmission rate in this region. These findings highlight the need to deploy initiatives to also tackle this Plasmodium species to eliminate malaria in the region.
Topics: Child; Adult; Animals; Humans; Infant; Child, Preschool; Adolescent; Young Adult; Middle Aged; Aged; Aged, 80 and over; Plasmodium malariae; Cameroon; Malaria; Malaria, Falciparum; Plasmodium falciparum; Anopheles; Prevalence; Forests
PubMed: 36698132
DOI: 10.1186/s13071-022-05635-7