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1.
Antimicrob Agents Chemother ; : e0004424, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39046237

ABSTRACT

The emergence and spread of chloroquine-resistant Plasmodium vivax have necessitated the assessment of alternative blood schizonticidal drugs. In Vietnam, chloroquine-resistant P. vivax malaria has been reported. In an open-label, single-arm trial, the safety, tolerability, and efficacy of pyronaridine-artesunate (Pyramax, PA) was evaluated in Dak Nong province, Vietnam. A 3-day course of PA was administered to adults and children (≥20 kg) infected with P. vivax. Patients also received primaquine (0.25 mg/kg daily for 14 days). PA was well tolerated with transient asymptomatic increases in liver transaminases. The per-protocol proportion of patients with day 42 PCR-unadjusted adequate clinical and parasitological response was 96.0% (95% CI, 84.9%-99.0%, n = 48/50). The median parasite clearance time was 12 h (range, 12-36 h), with a median fever clearance time of 24 h (range, 12-60 h). Single nucleotide polymorphisms (SNPs) as potential genetic markers of reduced drug susceptibility were analyzed in three putative drug resistance markers, Pvcrt-o, Pvmdr1, and PvK12. Insertion at position K10 of the Pvcrt-o gene was found in 74.6% (44/59) of isolates. Pvmdr1 SNPs at Y976F and F1076L were present in 61% (36/59) and 78% (46/59), respectively. Amplification of Pvmdr1 gene (two copies) was found in 5.1% (3/59) of parasite samples. Only 5.1% (3/59) of isolates had mutation 552I of the PvK12 gene. Overall, PA rapidly cleared P. vivax blood asexual stages and was highly efficacious in treating vivax malaria, with no evidence of artemisinin resistance found. PA provides an alternative to chloroquine treatment for vivax malaria in Vietnam. CLINICAL TRIALS: This study is registered with the Australian New Zealand Clinical Trials Registry as ACTRN12618001429246.

3.
PLoS Negl Trop Dis ; 18(4): e0012014, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38683855

ABSTRACT

BACKGROUND: Malaria elimination using current tools has stalled in many areas. Ivermectin (IVM) is a broad-antiparasitic drug and mosquitocide and has been proposed as a tool for accelerating progress towards malaria elimination. Under laboratory conditions, IVM has been shown to reduce the survival of adult Anopheles populations that have fed on IVM-treated mammals. Treating cattle with IVM has been proposed as an important contribution to malaria vector management, however, the impacts of IVM in this One Health use case have been untested in field trials in Southeast Asia. METHODS: Through a randomized village-based trial, this study quantified the effect of IVM-treated cattle on anopheline populations in treated vs. untreated villages in Central Vietnam. Local zebu cattle in six rural villages were included in this study. In three villages, cattle were treated with IVM at established veterinary dosages, and in three additional villages cattle were left as untreated controls. For the main study outcome, the mosquito populations in all villages were sampled using cattle-baited traps for six nights before, and six nights after a 2-day IVM-administration (intervention) period. Anopheline species were characterized using taxonomic keys. The impact of the intervention was analyzed using a difference-in-differences (DID) approach with generalized estimating equations (with negative binomial distribution and robust errors). This intervention was powered to detect a 50% reduction in total nightly Anopheles spp. vector catches from cattle-baited traps. Given the unusual diversity in anopheline populations, exploratory analyses examined taxon-level differences in the ecological population diversity. RESULTS: Across the treated villages, 1,112 of 1,523 censused cows (73% overall; range 67% to 83%) were treated with IVM. In both control and treated villages, there was a 30% to 40% decrease in total anophelines captured in the post-intervention period as compared to the pre-intervention period. In the control villages, there were 1,873 captured pre-intervention and 1,079 captured during the post-intervention period. In the treated villages, there were 1,594 captured pre-intervention, and 1,101 captured during the post-intervention period. The difference in differences model analysis comparing total captures between arms was not statistically significant (p = 0.61). Secondary outcomes of vector population diversity found that in three villages (one control and two treatment) Brillouin's index increased, and in three villages (two control and one treatment) Brillouin's index decreased. When examining biodiversity by trapping-night, there were no clear trends in treated or untreated vector populations. Additionally, there were no clear trends when examining the components of biodiversity: richness and evenness. CONCLUSIONS: The ability of this study to quantify the impacts of IVM treatment was limited due to unexpectedly large spatiotemporal variability in trapping rates; an area-wide decrease in trapping counts across all six villages post-intervention; and potential spillover effects. However, this study provides important data to directly inform future studies in the GMS and beyond for IVM-based vector control.


Subject(s)
Anopheles , Insecticides , Ivermectin , Malaria , Mosquito Vectors , Animals , Ivermectin/pharmacology , Cattle , Vietnam , Anopheles/drug effects , Malaria/prevention & control , Malaria/transmission , Mosquito Vectors/drug effects , Insecticides/pharmacology , Humans , Female , Mosquito Control/methods
4.
Infect Med (Beijing) ; 2(3): 229-236, 2023 Sep.
Article in English | MEDLINE | ID: mdl-38073881

ABSTRACT

Background: Strongyloidiasis, a neglected disease caused by intestinal nematodes of the genus, is endemic to tropical and subtropical areas such as Vietnam. Morphological methods only identify the genus, while DNA-molecular techniques are susceptible in Strongyloides spp. detection. The study aims to determine the prevalence of dominant Strongyloides species among the population in Duc Hoa district, Long An, Vietnam. Methods: A cross-sectional study used 1190 stool specimens collected from July 2017 to November 2018. All samples were transported within 2 h, stored at 2-8°C, and processed within 48 h for microscopy smear and culture at the Laboratory of Medical Parasitology, Pham Ngoc Thach University of Medicine (PNT). Then all positive samples with the above 2 methods were verified by real-time PCR technique. Real-time PCR amplification was conducted at the Laboratory of Molecular Biology, PNT. Results: Direct microscopy and modified Harada-Mori culture detected Strongyloides spp. larvae in 79/1190 samples (6.6%). About 94.2% of the DNA samples were Strongyloides stercoralis, 2.9% were co-infections with Strongyloides ratti and S. stercoralis, and 2.9% were patients with S. ratti. The identity of 12/14 sequences was confirmed as S. stercoralis with a high level of similarity (91.3%-100%) and over 98% for S. ratti. Conclusion: DNA-molecular techniques and sequence analysis are highly suitable for identifying Strongyloides species isolated from stool samples. It is remarkable evidence of the presence of zoonosis S. ratti disease in human, not just the known S. stercoralis. It is likely to result in a certain proportion of people being infected by this animal-borne infectious pathogen.

5.
Sci Rep ; 13(1): 20025, 2023 11 16.
Article in English | MEDLINE | ID: mdl-37973970

ABSTRACT

Plasmodium falciparum erythrocyte binding antigen 175 (PfEBA-175) plays essential role in erythrocyte invasion by the parasite and is a leading vaccine candidate. However, its genetic diversity in global isolates is a concern in developing an universal vaccine incorporating this protein. This study aimed to investigate genetic polymorphisms and natural selection of pfeba-175 region II (RII) in Myanmar and Vietnam P. falciparum isolates. Vietnam pfeba-175 RII displayed a low genetic polymorphism, while Myanmar pfeba-175 RII showed high levels of genetic diversity across the region. Point mutations, deletion, and recombinations were main factors contributing to genetic diversities in P. falciparum populations. Global pfeba-175 RII revealed similar, but not identical, genetic polymorphisms and natural selection profiles. Despite profiles of amino acid substitutions differed among populations, five major amino acid changes (K279E, E403K, K481I, Q584K, and R664) were commonly detected in global pfeba-175 RII populations. Haplotype network and genetic differentiation analyses of global pfeba-175 RII populations demonstrated no geographical relationships. Non-neglectable level of genetic diversity was observed in global pfeba-175 RII populations, emphasizing the need to consider this when designing an effective vaccine based on this protein. This study underscores the importance of the continuous monitoring of genetic diversity of pfeba-175 RII in the global P. falciparum populations.


Subject(s)
Malaria, Falciparum , Vaccines , Humans , Plasmodium falciparum/metabolism , Myanmar , Vietnam , Protozoan Proteins/metabolism , Antigens, Protozoan , Polymorphism, Genetic , Malaria, Falciparum/parasitology , Selection, Genetic , Erythrocytes/metabolism , Genetic Variation
6.
Indian J Otolaryngol Head Neck Surg ; 75(4): 2850-2855, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37974720

ABSTRACT

Aims: The objective of this study is to assess the effectiveness of the combined middle and inferior meatal antrostomy (MIMA) in management of patients with maxillary fungal sinusitis. Material and Methods: Design: retrospective cross sectional study. Setting and subjects: From September 2018 to March 2021, fifty-five patients with non-invasive maxillary fungal sinusitis, who underwent transnasal endoscopic combined MIMA. Methods: The study compared patients' pre- and post-operative subjective symptoms, including nasal obstruction, discharge, facial pain or pressure, halitosis, anosmia, and other non-specific symptoms. Endoscopic characteristics of recurrent fungal maxillary sinusitis and postoperative complications were also observed. Closure of the IMA site was evaluated at three and six months post-surgery and patients were categorized into three groups based on closure degree. Results: All clinical symptoms, including nasal discharge, nasal obstruction, nasal pruritus, anosmia, halitosis, sneezing, facial pain, ophthalmic and otologic symptoms, were resolved over six months after combined MIMA in majority of cases (94 - 100%). After three and six months, the postoperative endoscopic evaluation revealed recurrent fungal maxillary sinusitis in 1.8% and 5.4% of cases, respectively. Partial stenosis of the inferior antrostomy was observed in 7.2% and 16% of cases, while complete stenosis was noted in 3.6% and 7.2% of cases after three months and six months. Conclusions: The combined MIMA is effective and has better outcomes than the medial meatal antrostomy approach alone without additional operative time. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-023-03863-6.

7.
Cureus ; 15(9): e44574, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37790044

ABSTRACT

Ganoderma lucidum is traditionally used to prevent and treat some diseases such as liver disorders, hypertension, insomnia, diabetes, and cancer. G. lucidum spore extracts are also reported to share similar bioactivities as extracts from its other parts. However, there is no systematic review that elucidates its pharmacological effect. Our aim is to comprehensively summarise current evidence of G. lucidum spore extracts to clarify its benefits to be applied in further studies. We searched five primary databases: PubMed, Virtual Health Library (VHL), Global Health Library (GHL), System for Information on Grey Literature in Europe (SIGLE), and Google Scholar on September 13, 2021. Articles were selected according to inclusion and exclusion criteria. A manual search was applied to find more relevant articles. Ninety studies that reported the pharmacological effects and/or safety of G. lucidum spores were included in this review. The review found that G. lucidum spore extracts showed quite similar effects as other parts of this medicinal plant including anti-tumor, anti-inflammatory, antioxidant effects, and immunomodulation. G. lucidum sporoderm-broken extract demonstrated higher efficiency than unbroken spore extract. G. lucidum extracts also showed their effects on some genes responsible for the body's metabolism, which implied the benefits in metabolic diseases. The safety of G. lucidum should be investigated in depth as high doses of the extract could increase levels of cancer antigen (CA)72-4, despite no harmful effect shown on body organs. Generally, there is a lot of potential in the studies of compounds with pharmacological effects and new treatments. Sporoderm breaking technique could contribute to the production of extracts with more effective prevention and treatment of diseases. High doses of G. lucidum spore extract should be used with caution as there was a concern about the increase in CA.

8.
Cureus ; 15(4): e37267, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37162770

ABSTRACT

Diabetes mellitus is a chronic metabolic disease relating to steady hyperglycemia resulting from the impairment of the endocrine and non-endocrine systems. Many new drugs having varied targets were discovered to treat this disease, especially type 2 diabetes. Among those, α-glucosidase inhibitors showed their effects by preventing the digestion of carbohydrates through their inhibition against α-amylase and α-glucosidase. Recently, chalcones have attracted considerable attention as they have a simple structure, are easily synthesized as well as have a variety of derivatives. Some reports suggested that chalcone and its derivates could inhibit α-amylase and α-glucosidase. This narrative review provides a comprehensive evaluation of the inhibition of chalcone and its derivatives against α-amylase and α-glucosidase that were reviewed and reported in published scientific articles. Twenty-eight articles were reviewed after screening 207 articles found in four databases, including PubMed, Google Scholar, VHL (Virtual Health Library), and GHL (Global Health Library). This review presented the inhibitory effects of varied chalcones, including chalcones with a basic structural framework, azachalcones, bis-chalcones, chalcone oximes, coumarin-chalcones, cyclohexane chalcones, dihydrochalcones, and flavanone-coupled chalcones. Many of these chalcones had significant inhibition against α-amylase as well as α-glucosidase that were comparable to or even stronger than standard inhibitors. This suggested that such compounds could be potential candidates for the discovery of new anti-diabetic remedies in the years to come.

9.
Front Pharmacol ; 14: 1156655, 2023.
Article in English | MEDLINE | ID: mdl-38410524

ABSTRACT

Background: Uncontrolled blood pressure is a major risk factor for cardiovascular diseases. Fixed-dose combination (FDC) therapy offers a promising approach to addressing this challenge by providing a convenient single-tablet solution that enhances the effectiveness of blood pressure control. In our systematic review, we assess the effectiveness of perindopril/amlodipine FDC in managing blood pressure. Methods: We conducted a comprehensive search across four primary electronic databases, namely, PubMed, Virtual Health Library (VHL), Global Health Library (GHL), and Google Scholar, as of 8 February 2022. Additionally, we performed a manual search to find relevant articles. The quality of the selected articles was evaluated using the Study Quality Assessment Tools (SQAT) checklist from the National Institute of Health and the ROB2 tool from Cochrane. Results: Our systematic review included 17 eligible articles. The findings show that the use of perindopril/amlodipine FDC significantly lowers blood pressure and enhances the quality of blood pressure control. Compared to the comparison group, the perindopril/amlodipine combination tablet resulted in a higher rate of blood pressure response and normalization. Importantly, perindopril/amlodipine FDC contributes to improved patient adherence with minimal side effects. However, studies conducted to date have not provided assessments of the cost-effectiveness of perindopril/amlodipine FDC. Conclusion: In summary, our analysis confirms the effectiveness of perindopril/amlodipine FDC in lowering blood pressure, with combination therapy outperforming monotherapy and placebo. Although mild adverse reactions were observed in a small subset of participants, cost-effectiveness assessments for this treatment remain lacking in the literature.

10.
Pathogens ; 11(10)2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36297215

ABSTRACT

The circumsporozoite surface protein of Plasmodium vivax (PvCSP) plays a critical role in parasite biology. It has been extensively studied as a leading vivax-malaria-vaccine candidate. In this study, the genetic polymorphism and natural selection of pvcsp in P. vivax isolates collected from the Central Highlands, Vietnam were analyzed to understand the genetic structure of the parasite circulating in the endemic area and to provide baseline information for effective vaccine development based on the protein. Only two major alleles, VK210 and VK247, were detected in Vietnamese pvcsp, with VK247 being the predominant one. The N-terminal and C-terminal regions of Vietnamese VK210 and VK247 variants showed a low genetic diversity. Amino acid substitutions, insertions of a single amino acid or octapeptide (ANKKAEDA in VK210 and ANKKAGDA in VK247), and tetrapeptide repeat motifs (GGNA) were the main factors generating genetic diversity in the two regions of the Vietnamese VK210 and VK247 variants. Interestingly, these two regions of Vietnamese pvcsp displayed a unique natural selection pressure distinct from global pvcsp, particularly with the neighboring Southeast Asian pvcsp population. Meanwhile, the central repeat region (CRR) in both the VK210 and VK247 variants showed a high degree of polymorphic characters, caused by varying numbers, types, and combinations of peptide repeat motifs (PRMs) in Vietnamese pvcsp. Highly complicated polymorphic patterns of the CRR were also detected in global pvcsp. These results expand our understanding of the genetic structure of Vietnamese pvcsp and the population dynamics of P. vivax in the Central Highlands, Vietnam.

11.
Environ Monit Assess ; 194(8): 561, 2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35789439

ABSTRACT

A coal-fired power plant's operation can release radioactive nuclides and radon gas into the environment, affecting the surrounding ecosystem. In this work, the collective effective dose due to the inhalation and the consumption of food containing the deposited radionuclides from the atmospheric release of the plants were evaluated. The results show that the radioactivity concentration in coal and fly ash samples depends on the origin of feed coal. The distribution of Th and U radionuclides in the 6a1 dust coal and bituminous coal is different. In general, the collective effective dose for different organs due to radiation exposure from the atmospheric release of two surveyed CFPP complexes are lower than the corresponding value published by UNSCEAR.


Subject(s)
Ecosystem , Radiation Exposure , Coal/analysis , Environmental Monitoring , Power Plants , Radioisotopes/analysis , Vietnam
12.
Heliyon ; 8(4): e09313, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35497027

ABSTRACT

Cascabela peruviana (L.) Lippold (C. peruviana) has been extensively used for its antifungal and antibacterial properties. However, its role in anti-insect is still under investigation. To investigate the ability of the ethanol extract of C. peruviana against insects, we used the fruit fly (Drosophila melanogaster) as a model to gain more insight into the toxic effects of this extract. We found that the ethanol extract from the stem and leaves of C. peruviana was effective against insects and contained polyphenol and flavonoid compounds. C. peruviana could induce mortality of 2nd-instar larvae and reduce growth and reproduction of fruit flies. Interestingly, the toxicity of C. peruviana extract has been remained to affect the development of the next generation of fruit flies. The locomotor activity and feeding ability of the F1 generation of this insect were significantly reduced by C. peruviana. In addition, flavonoids and polyphenols, as well as saponins and tannins were detected in the ethanol extract of C. peruviana. We assume that the ability of the extract of C. peruviana to control insects may be related to the presence of high levels of these compounds. The findings highlighted that the extract from the leaves of Cascabela peruviana has the potential to be used as an insecticide.

13.
Glob Qual Nurs Res ; 9: 23333936211070267, 2022.
Article in English | MEDLINE | ID: mdl-35282501

ABSTRACT

This research draws on broader inquiry that explores the construction of the spatial positioning of nurses in Vietnam and how power structures sustained that positioning. Observations and individual interviews were undertaken with 32 registered nurses. Analysis of participant data and relevant policy documents moved beyond coding to theorising and thus to the abstraction of key concepts. Social space and social value were significant concepts developed in the research. The concept of space reflected the ways in which nurses constantly engaged in processes of negotiation to embed a sense of control over their practice. The related concept of social value brought focus to a power structure whereby the fiscal priorities of health care managers reinforced a disconnect between the use and exchange values of nurses. An interpretation of power relations that underpinned the material and symbolic spaces in which nurses worked was framed within the historical context of Vietnam. Tóm lÆ°Æ°oc Bài báo này dua trên nghiên cuu voi qui mô lon hÆ¡n nham tìm hieu vi the cua nghành dieu dÆ°ong tai Viet Nam. PhÆ°Æ¡ng pháp quan sát và phong van cá nhân dÆ°oc thuc hien voi 32 nhân viên dieu dÆ°ong làm viec tai tám khoa cua mot benh vien o Viet Nam. Viec phân tích du lieu cua ngÆ°oi tham gia và các tài lieu ve chính sách liên quan dã vÆ°ot ra khoi pham vi mã hóa du lieu dÆ¡n thuan, mo rong sang hoc thuyet và chuyen sang truu tÆ°ong hóa các khái niem chính. Không gian xã hoi và giá tri xã hoi là nhung khái niem quan trong dÆ°oc phát trien trong nghiên cuu này. Khái niem ve không gian phan ánh cách thuc mà các nhân viên dieu dÆ°ong liên tuc tham gia vào các quá trình thÆ°Æ¡ng lÆ°ong de kiem soát dÆ°oc viec thuc hành cua ho. Khái niem liên quan ve giá tri xã hoi tap trung vào cÆ¡ cau quyen luc, theo dó Æ°u tiên tài chính cua các nhà quan lý cham sóc suc khoe góp phan làm gián doan moi liên ket giua giá tri su dung và giá tri trao doi mà ngành dieu dÆ°ong mang lai. Lý giai ve các moi quan he quyen luc dã dÆ°oc cung co trong không gian thuc và không gian mang tính bieu tÆ°ong nÆ¡i các dieu dÆ°ong làm viec, dÆ°oc dinh hình trong boi canh lich su cua Viet Nam.

14.
Genes (Basel) ; 12(12)2021 11 27.
Article in English | MEDLINE | ID: mdl-34946853

ABSTRACT

Apical membrane antigen-1 of Plasmodium falciparum (PfAMA-1) is a leading malaria vaccine candidate antigen. However, the genetic diversity of pfama-1 and associated antigenic variation in global P. falciparum field isolates are major hurdles to the design of an efficacious vaccine formulated with this antigen. Here, we analyzed the genetic structure and the natural selection of pfama-1 in the P. falciparum population of Vietnam. A total of 37 distinct haplotypes were found in 131 P. falciparum Vietnamese isolates. Most amino acid changes detected in Vietnamese pfama-1 were localized in the ectodomain, domains I, II, and III. Overall patterns of major amino acid changes in Vietnamese pfama-1 were similar to those of global pfama-1, but the frequencies of the amino acid changes slightly differed by country. Novel amino acid changes were also identified in Vietnamese pfama-1. Vietnamese pfama-1 revealed relatively lower genetic diversity than currently analyzed pfama-1 in other geographical regions, and suggested a distinct genetic differentiation pattern. Evidence for natural selection was detected in Vietnamese pfama-1, but it showed purifying selection unlike the global pfama-1 analyzed so far. Recombination events were also found in Vietnamese pfama-1. Major amino acid changes that were commonly identified in global pfama-1 were mainly localized to predicted B-cell epitopes, RBC-binding sites, and IUR regions. These results provide important information for understanding the genetic nature of the Vietnamese pfama-1 population, and have significant implications for the design of a vaccine based on PfAMA-1.


Subject(s)
Antigens, Protozoan/genetics , Antigens, Protozoan/immunology , Haplotypes , Malaria, Falciparum/pathology , Membrane Proteins/genetics , Membrane Proteins/immunology , Plasmodium falciparum/genetics , Polymorphism, Genetic , Protozoan Proteins/genetics , Protozoan Proteins/immunology , Selection, Genetic , Antigens, Protozoan/chemistry , Humans , Malaria, Falciparum/genetics , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Membrane Proteins/chemistry , Plasmodium falciparum/immunology , Plasmodium falciparum/isolation & purification , Protozoan Proteins/chemistry , Sequence Homology, Amino Acid , Vietnam
15.
PLoS One ; 16(10): e0258580, 2021.
Article in English | MEDLINE | ID: mdl-34669697

ABSTRACT

Asymptomatic parasite carriers represent a "silent" infective reservoir for malaria transmission and contributes to malaria persistence. However, limited data are available on asymptomatic malaria in Vietnam. Between November 2018 and March 2019, we conducted a malaria epidemiological survey of asymptomatic people (children ≥ 10 years old and adults ≥18 years old, n = 2,809) residing in three communes in Tuy Duc district, Dak Nong province in the Central Highlands of Vietnam. Based on the national stratification of malaria risk, Dak Buk So, Dak Ngo and Quang Truc communes were classified by the National Malaria Control Programme as low, moderate and high malaria endemic areas, respectively. Using participants' finger prick blood samples, malaria parasites were detected by one-step reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The median age (Interquartile Range) for adults and children were 35 years (26-50) and 12 years (11-14), respectively. The prevalence of asymptomatic malaria was 1.7% (22/1,328), 3.5% (31/890) and 12.2% (72/591) for participants from Dak Buk So, Dak Ngo and Quang Truc, respectively. The prevalence of asymptomatic malaria was lower in children compared to adults: 2.6% (9/352) versus 4.7% (116/2,457) (Odds Ratio 0.53, 95% Confidence Interval 0.28 to1.02). Ownership of long-lasting insecticide-treated bed nets and hammocks was 97.1%, 99.0% and 94.7% for participants in Dak Buk So, Dak Ngo and Quang Truc, respectively, however, only 66.0%, 57.3% and 42.8% of the participants reported using bed nets every night. Of the several risk factors examined, going to the forest two weeks prior to enrolment into the study and sleeping in the forest had a significant association with participants being infected with asymptomatic malaria in Quang Truc, but not in the other two communes. Knowledge of the prevalence and distribution of asymptomatic malaria will help design and evaluate future intervention strategies for malaria elimination in Vietnam.


Subject(s)
Malaria, Falciparum , Adolescent , Adult , Child , Child, Preschool , Humans , Male , Young Adult
16.
Antimicrob Agents Chemother ; 65(12): e0027621, 2021 11 17.
Article in English | MEDLINE | ID: mdl-34570647

ABSTRACT

The rise in Plasmodium falciparum resistance to dihydroartemisinin-piperaquine in Vietnam justifies the need to evaluate alternative artemisinin-based combination therapies. Between July 2018 and October 2019, a single-arm trial of pyronaridine-artesunate (Pyramax, PA) was conducted in Dak Nong province, Vietnam. PA (3-day course) was administered to adults and children infected with P. falciparum. PA was well tolerated by the participants. The proportion of patients with Day 42 PCR-corrected adequate clinical and parasitological response was 95.2% (95% confidence interval [CI], 82.3 to 98.8, n = 40/42) for treating falciparum malaria. The median parasite clearance half-life was 6.7 h (range, 2.6 to 11.9) and the median parasite clearance time was 72 h (range, 12 to 132) with 44.9% (22/49) of patients having positive blood films at 72 h. The two patients that recrudesced had comparable Day 7 blood pyronaridine concentrations (39.5 and 39.0 ng/ml) to the 40 patients who did not recrudesce (median 43.4 ng/ml, 95% CI, 35.1 to 54.9). Ring-stage and piperaquine survival assays revealed that of the 29 P. falciparum isolates collected from the patients before PA treatment, 22 (75.9%) had reduced susceptibility to artemisinins and 17 (58.6%) were resistant to piperaquine. Genotyping confirmed that 92.0% (46/50) of falciparum patients were infected with parasites bearing the Pfkelch13 C580Y mutation associated with artemisinin resistance. Of these, 56.0% (28/50) of the isolates also had multiple copies of the plasmepsin 2/3 genes responsible for piperaquine resistance. Overall, PA was effective in treating P. falciparum in the Central Highlands of Vietnam. (This study has been registered at AustralianClinicalTrials.gov.au under trial ID ACTRN12618001429246.).


Subject(s)
Antimalarials , Artemisinins , Malaria, Falciparum , Quinolines , Antimalarials/pharmacology , Antimalarials/therapeutic use , Artemisinins/therapeutic use , Artesunate , Drug Combinations , Humans , Malaria, Falciparum/drug therapy , Naphthyridines , Plasmodium falciparum/genetics , Quinolines/therapeutic use , Vietnam
17.
Elife ; 102021 08 10.
Article in English | MEDLINE | ID: mdl-34372970

ABSTRACT

Background: National Malaria Control Programmes (NMCPs) currently make limited use of parasite genetic data. We have developed GenRe-Mekong, a platform for genetic surveillance of malaria in the Greater Mekong Subregion (GMS) that enables NMCPs to implement large-scale surveillance projects by integrating simple sample collection procedures in routine public health procedures. Methods: Samples from symptomatic patients are processed by SpotMalaria, a high-throughput system that produces a comprehensive set of genotypes comprising several drug resistance markers, species markers and a genomic barcode. GenRe-Mekong delivers Genetic Report Cards, a compendium of genotypes and phenotype predictions used to map prevalence of resistance to multiple drugs. Results: GenRe-Mekong has worked with NMCPs and research projects in eight countries, processing 9623 samples from clinical cases. Monitoring resistance markers has been valuable for tracking the rapid spread of parasites resistant to the dihydroartemisinin-piperaquine combination therapy. In Vietnam and Laos, GenRe-Mekong data have provided novel knowledge about the spread of these resistant strains into previously unaffected provinces, informing decision-making by NMCPs. Conclusions: GenRe-Mekong provides detailed knowledge about drug resistance at a local level, and facilitates data sharing at a regional level, enabling cross-border resistance monitoring and providing the public health community with valuable insights. The project provides a rich open data resource to benefit the entire malaria community. Funding: The GenRe-Mekong project is funded by the Bill and Melinda Gates Foundation (OPP11188166, OPP1204268). Genotyping and sequencing were funded by the Wellcome Trust (098051, 206194, 203141, 090770, 204911, 106698/B/14/Z) and Medical Research Council (G0600718). A proportion of samples were collected with the support of the UK Department for International Development (201900, M006212), and Intramural Research Program of the National Institute of Allergy and Infectious Diseases.


Subject(s)
Communicable Disease Control/statistics & numerical data , Disease Eradication/statistics & numerical data , Drug Resistance/genetics , Malaria/prevention & control , Plasmodium/genetics , Animals , Asia, Southeastern , Bangladesh , Democratic Republic of the Congo , India , Plasmodium/drug effects
18.
Trop Med Int Health ; 26(11): 1419-1426, 2021 11.
Article in English | MEDLINE | ID: mdl-34370367

ABSTRACT

OBJECTIVES: Human toxocariasis is a widespread zoonosis for which a chemotherapy decision and therapy effectiveness are difficult to determine. We aimed to investigate the kinetic profile of clinical and laboratory findings and treatment outcome of patients with toxocariasis in Vietnam. METHODS: The prospective study was conducted between October 2017 and June 2019. The diagnosis of toxocariasis was established based on clinical, laboratory (eosinophilia, raised IgE concentration) and serological (positive Toxocara IgG ELISA) evaluation as well as the exclusion of another helminthic co-infection. The patients were followed up after seven days, then one, three and six months after chemotherapy by thiabendazole. RESULTS: The study involved 80 patients with a mean age of 41.6 ± 15.2 years of whom 58.8% were female. At three and six months after chemotherapy, most patients demonstrated resolution of clinical signs and symptoms, eosinophil count and IgE concentration but not in the proportion of IgG seropositivity. Skin lesions and eosinophilia resolved earlier than the other symptoms (one month after treatment). About four-fifths of the patients were "cured" after three and six months of follow-up; 33.8% showed side effects to thiabendazole therapy but no severe events were reported. The most common adverse reaction was neurologic symptoms followed by gastrointestinal or skin manifestations which lasted as long as 4 days. CONCLUSIONS: In toxocariasis patients, cutaneous manifestations and eosinophilia resolve more rapidly than other clinical and laboratory findings while IgG titre has a very slow kinetic after therapy. Thiabendazole seems to be a potential alternative for the treatment of human toxocariasis.


Subject(s)
Toxocariasis/diagnosis , Adolescent , Adult , Aged , Animals , Anthelmintics/administration & dosage , Anthelmintics/therapeutic use , Antibodies, Helminth/blood , Female , Humans , Male , Middle Aged , Prospective Studies , Thiabendazole/administration & dosage , Thiabendazole/therapeutic use , Toxocara/immunology , Toxocariasis/blood , Toxocariasis/drug therapy , Toxocariasis/epidemiology , Vietnam/epidemiology , Young Adult , Zoonoses/diagnosis , Zoonoses/drug therapy
19.
BMJ Case Rep ; 14(7)2021 Jul 15.
Article in English | MEDLINE | ID: mdl-34266828

ABSTRACT

We reported a case of gnathostomiasis in a 42-year-old woman with an unclear history of eating high-risk foods and had a non-migratory skin lesion, negative serological testing and normal blood eosinophil counts. A diagnosis of gnathostomiasis was based on a live, third-stage Gnathostoma spinigerum larva that was randomly taken from the patient's skin lesion by herself. The presenting case report demonstrates challenges in correctly diagnose cutaneous gnathostomiasis even in endemic countries due to atypical skin lesions, negative serology testing and the absence of eosinophilia and thus, the widely used classic triad of suggestive evidence of gnathostomiasis is not fulfilled.


Subject(s)
Gnathostoma , Gnathostomiasis , Larva Migrans , Adult , Animals , Female , Gnathostomiasis/diagnosis , Gnathostomiasis/drug therapy , Humans , Larva , Larva Migrans/diagnosis , Larva Migrans/drug therapy , Vietnam
20.
Parasitol Int ; 83: 102374, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33957296

ABSTRACT

Vietnam achieved outstanding success against malaria in the last few decades. The mortality and morbidity of malaria in Vietnam have decreased remarkably in recent years, but malaria is still a major public health concern in the country, particularly in the Central Highlands region. In this study, molecular analyses of malaria parasites in the Central Highlands were performed to understand the population structure and genetic diversity of the parasites circulating in the region. Plasmodium falciparum (68.7%) and P. vivax (27.4%) along with mixed infections with P. falciparum/P. vivax (3.9%) were detected in 230 blood samples from patients with malaria. Allele-specific nested-polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism (PCR-RFLP) analyses of pfmsp-1, pfama-1, pvcsp, and pvmsp-1 revealed complex genetic makeup in P. falciparum and P. vivax populations of Vietnam. Substantial multiplicity of infection (MOI) was also identified, suggesting significant genetic diversity and polymorphism of P. falciparum and P. vivax populations in the Central Highlands of Vietnam. These results provide fundamental insight into the current patterns of dispersion and genetic nature of malaria parasites as well as for the development of malaria elimination strategies in the endemic region.


Subject(s)
Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Plasmodium falciparum/isolation & purification , Plasmodium vivax/isolation & purification , Adult , Epidemiological Monitoring , Female , Genetic Variation , Humans , Malaria, Falciparum/parasitology , Malaria, Vivax/parasitology , Male , Middle Aged , Plasmodium falciparum/genetics , Plasmodium vivax/genetics , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , Prevalence , Protozoan Proteins/analysis , Vietnam/epidemiology , Young Adult
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