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1.
Antimicrob Agents Chemother ; 68(5): e0121123, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38563751

ABSTRACT

Helminthiasis remains a public health issue in endemic areas. Various drugs have been proposed to improve efficacy against helminths. The study aimed to assess the safety and efficacy of three different anthelmintic combinations to treat Trichuris trichiura infections. We conducted a randomized assessors-blind clinical trial involving children aged 2-17 years with T. trichiura. Participants were randomly assigned to one of three treatment arms. On the first and third days, all participants got albendazole 400 mg, and on the second day, albendazole (arm A), mebendazole 500 mg (arm B), or pyrantel 125 mg/kg (arm C). We assessed treatment efficacy using the cure rate (CR) and egg reduction rate (ERR) at 3 and 6 weeks post-treatment. At 3 weeks post-treatment, ERR and CR were highest in study arm A [ERR = 94%, 95% confidence interval (CI): 92-95; CR = 71%; 95% CI: 58-81] compared to the B and C arms. Decrease in ERR was significant only for arm B versus arm A (P-value <0.001); decrease in ERR was significant for arms B and C (P-value <0.001). No statistical difference was observed in CR when comparing arms A and B (P-value =1.00) and C (P-value =0.27). At 6 weeks, a decrease in ERR was observed in three arms, significant only for arm C, 81% (95% CI: 78-83). A significant increase in egg counts was observed between 3 and 6 weeks post-treatment. All treatments were safe with mild adverse events. Albendazole 400 mg/day (arm A) showed the highest efficacy against trichuriasis. Nonetheless, this treatment regimen was able to cure half of the treated individuals highlighting concerns about controlling the transmission of T. trichiura.CLINICAL TRIALRegistered at ClinicalTrials.gov (NCT04326868).


Subject(s)
Albendazole , Anthelmintics , Mebendazole , Pyrantel , Trichuriasis , Trichuris , Humans , Albendazole/therapeutic use , Albendazole/adverse effects , Albendazole/administration & dosage , Child , Mebendazole/therapeutic use , Trichuriasis/drug therapy , Male , Female , Trichuris/drug effects , Animals , Child, Preschool , Anthelmintics/therapeutic use , Anthelmintics/adverse effects , Anthelmintics/administration & dosage , Adolescent , Pyrantel/therapeutic use , Drug Therapy, Combination , Treatment Outcome , Parasite Egg Count
2.
Helminthologia ; 61(1): 11-19, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38659469

ABSTRACT

This study investigates the presence of Trichuris trichiura eggs in soil samples collected from urban areas in Lahore, Pakistan. A total of 3600 soil samples were collected over two years from Lahore's urban regions. The detection of helminth eggs in these samples was performed using sodium hypochlorite (NaOCl) as a diagnostic technique. The study reveals an overall prevalence rate of T. trichiura at 0.97 % (35 out of 3600) in the contaminated soil samples from Lahore's slum areas. When analyzing the data by geographical areas, the study found the highest prevalence of T. trichiura in Allama Iqbal Town (1.83 %, 11 out of 600), followed by Samanabad (1.16 %, 7 out of 600), Wapda Town (1.00 %, 6 out of 600), Gulberg (1.00 %, 6 out of 600), and Cantt (0.50 %, 3 out of 600). Conversely, Valencia Town had the lowest prevalence rate at 0.33 % (2 out of 600). However, these variations in prevalence rates were not statistically significant (p = 0.117). Prevalence rates of T. trichiura's eggs varied significantly across different sampling seasons (p>0.001). In autumn, a total of 900 soil samples were collected, with 19 samples (2.11 %) testing positive for T. trichiura. This rate was notably higher compared to the prevalence rates observed in winter, spring, and summer, which were 0.66 %, 0.22 %, and 0.88 %, respectively. Regarding the sampling months, the study observed a significantly higher prevalence during September (3.33 %, 10 out of 300), followed by October (2.33 %, 7 out of 300), and August (1.33 %, 4 out of 300). Prevalence rates gradually decreased in other months, ranging from 1 % to 0.33 % (3 to 1 out of 300), with no parasite detection in March (0 %, 0 out of 300) (p < 0.001). This research underscores soil contamination due to fecal waste and highlights public unawareness of parasite biology, driven by open defecation practices.

3.
J Investig Med High Impact Case Rep ; 12: 23247096231224328, 2024.
Article in English | MEDLINE | ID: mdl-38193443

ABSTRACT

Trichuriasis is a neglected tropical disease caused by Trichuris trichiura that spreads through the ingestion of embryonated eggs in contaminated soil, water, or food. In nonendemic areas, T trichiura infestation is very rare and sporadic and is often diagnosed in immigrants from endemic countries such as the Philippines. Whipworms feed on human blood and also erode the colonic mucosa, thereby evoking an inflammatory response. In milder forms, trichuriasis can be asymptomatic and often an incidental diagnosis on screening colonoscopy. Heavily infested patients usually present with abdominal pain, nausea, vomiting, tenesmus, chronic diarrhea, iron deficiency anemia, or stunted growth. T trichiura worms can be removed with biopsy forceps during a colonoscopy; however, most patients require a course of albendazole, mebendazole, or ivermectin. We describe a unique case of T trichiura as an incidental finding during a screening colonoscopy. The whipworms were retrieved using biopsy forceps and the patient was treated with albendazole. At the time of the colonoscopy, the patient did not exhibit any specific symptoms related to the worm infestation.


Subject(s)
Trichuriasis , Trichuris , Humans , Animals , Trichuriasis/diagnosis , Trichuriasis/drug therapy , Albendazole/therapeutic use , Incidental Findings , Colonoscopy
4.
Parasitology ; 150(12): 1096-1104, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37655745

ABSTRACT

From the safety inside vehicles, Knowsley Safari offers visitors a close-up encounter with captive olive baboons. As exiting vehicles may be contaminated with baboon stool, a comprehensive coprological inspection was conducted to address public health concerns. Baboon stools were obtained from vehicles, and sleeping areas, inclusive of video analysis of baboon­vehicle interactions. A purposely selected 4-day sampling period enabled comparative inspections of 2662 vehicles, with a total of 669 baboon stools examined (371 from vehicles and 298 from sleeping areas). As informed by our pilot study, front-line diagnostic methods were: QUIK-CHEK rapid diagnostic test (RDT) (Giardia and Cryptosporidium), Kato­Katz coproscopy (Trichuris) and charcoal culture (Strongyloides). Some 13.9% of vehicles were contaminated with baboon stool. Prevalence of giardiasis was 37.4% while cryptosporidiosis was <0.01%, however, an absence of faecal cysts by quality control coproscopy, alongside lower than the expected levels of Giardia-specific DNA, judged RDT results as misleading, grossly overestimating prevalence. Prevalence of trichuriasis was 48.0% and strongyloidiasis was 13.7%, a first report of Strongyloides fuelleborni in UK. We advise regular blanket administration(s) of anthelminthics to the colony, exploring pour-on formulations, thereafter, smaller-scale indicator surveys would be adequate.


Subject(s)
Cryptosporidiosis , Cryptosporidium , Giardiasis , Intestinal Diseases, Parasitic , Parasites , Animals , Humans , Papio anubis , Cryptosporidiosis/parasitology , Pilot Projects , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/veterinary , Giardiasis/epidemiology , Papio/parasitology , Giardia , Strongyloides , Feces/parasitology , United Kingdom
5.
Adv Parasitol ; 121: 1-63, 2023.
Article in English | MEDLINE | ID: mdl-37474238

ABSTRACT

The mouse whipworm, Trichuris muris, has been used for over 60 years as a tractable model for human trichuriasis, caused by the related whipworm species, T. trichiura. The history of T. muris research, from the discovery of the parasite in 1761 to understanding the lifecycle and outcome of infection with different doses (high versus low dose infection), as well as the immune mechanisms associated with parasite expulsion and chronic infection have been detailed in an earlier review published in 2013. Here, we review recent advances in our understanding of whipworm biology, host-parasite interactions and basic immunology brought about using the T. muris mouse model, focussing on developments from the last decade. In addition to the traditional high/low dose infection models that have formed the mainstay of T. muris research to date, novel models involving trickle (repeated low dose) infection in laboratory mice or infection in wild or semi-wild mice have led to important insights into how immunity develops in situ in a multivariate environment, while the use of novel techniques such as the development of caecal organoids (enabling the study of larval development ex vivo) promise to deliver important insights into host-parasite interactions. In addition, the genome and transcriptome analyses of T. muris and T. trichiura have proven to be invaluable tools, particularly in the context of vaccine development and identification of secreted products including proteins, extracellular vesicles and micro-RNAs, shedding further light on how these parasites communicate with their host and modulate the immune response to promote their own survival.


Subject(s)
Trichuriasis , Trichuris , Mice , Humans , Animals , Trichuris/genetics , Life Cycle Stages , Host-Parasite Interactions
6.
PeerJ ; 10: e13401, 2022.
Article in English | MEDLINE | ID: mdl-35539016

ABSTRACT

Hosts and their microbiota and parasites have co-evolved in an adaptative relationship since ancient times. The interaction between parasites and intestinal bacteria in terms of the hosts' health is currently a subject of great research interest. Therapeutic interventions can include manipulations of the structure of the intestinal microbiota, which have immunological interactions important for modulating the host's immune system and for reducing inflammation. Most helminths are intestinal parasites; the intestinal environment provides complex interactions with other microorganisms in which internal and external factors can influence the composition of the intestinal microbiota. Moreover, helminths and intestinal microorganisms can modulate the host's immune system either beneficially or harmfully. The immune response can be reduced due to co-infection, and bacteria from the intestinal microbiota can translocate to other organs. In this way, the treatment can be compromised, which, together with drug resistance by the parasites makes healing even more difficult. Thus, this work aimed to understand interactions between the microbiota and parasitic diseases caused by the most important geohelminths and schistosomiasis and the consequences of these associations.


Subject(s)
Gastrointestinal Microbiome , Helminths , Microbiota , Parasites , Schistosomiasis , Animals , Intestines/microbiology , Helminths/microbiology
7.
Front Immunol ; 13: 800295, 2022.
Article in English | MEDLINE | ID: mdl-35197976

ABSTRACT

Trichuriasis is one of the most common neglected tropical diseases of the world's poorest people. A recombinant vaccine composed of Tm-WAP49, an immunodominant antigen secreted by adult Trichuris stichocytes into the mucosa of the cecum to which the parasite attaches, is under development. The prototype is being evaluated in a mouse model of Trichuris muris infection, with the ultimate goal of producing a mucosal vaccine through intranasal delivery. Intranasal immunization of mice with Tm-WAP49 formulated with the adjuvant OCH, a truncated analog of alpha-GalCer with adjuvanticity to stimulate natural killer T cells (NKT) and mucosal immunity, induced significantly high levels of IgG and its subclasses (IgG1 and IgG2a) in immunized mice. This also resulted in a significant reduction of worm burden after challenge with T. muris-infective eggs. The addition of QS-21 adjuvant to this vaccine formulation further reduced worm counts. The improved protection from the dual-adjuvanted vaccine correlated with higher serum antibody responses (IgG, IgG1, IgG2a, IgA) as well as with the induction of antigen-specific IgA in the nasal mucosa. It was also associated with the robust cellular responses including functional subsets of CD4 T cells producing IL-4, and cytotoxic CD8 T cells expressing granzyme B. The worm reduction achieved by mucosal immunization was higher than that induced by subcutaneous immunization. Intranasal immunization also induced a significantly higher nasal mucosa-secreted antigen-specific IgA response, as well as higher functional cellular responses including CD4+IL4+ (Th1) and CD8+GnzB+ (Th2) T cells, and antigen-specific INFγ-producing T cells in both spleen and MLNs and antibody-producing B cells (CD19+B220+/B220+GL7+). Mucosal immunization further induced long-term T lymphocyte memory with increased central (CD62L+CD44+) and effector (CD62L-CD44+) memory subsets of both CD4 and CD8 T cells at 60 days after the last immunization. In summary, intranasal immunization with recombinant Tm-WAP49 protein induced strong protection versus murine trichuriasis. It represents a promising vaccination approach against intestinal nematodes.


Subject(s)
Trichuriasis/immunology , Adjuvants, Immunologic/pharmacology , Administration, Intranasal , Animals , Antibody Formation/drug effects , CD8-Positive T-Lymphocytes/immunology , Female , Immunity, Cellular/drug effects , Immunity, Mucosal/immunology , Immunization , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Mice , Mice, Inbred AKR , Mice, Inbred BALB C , Mucous Membrane/immunology , Th1 Cells/immunology , Trichuris/immunology , Vaccination/methods , Vaccines, Synthetic
8.
Parasitol Res ; 121(1): 1-10, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34993634

ABSTRACT

Trichuriasis is one of the most common soil-transmitted helminth (STH) infections, affecting populations globally. The condition is particularly prevalent in tropical and subtropical areas with low levels of sanitation and poor living conditions. The objective of this systematic review and meta-analysis was to evaluate the prevalence of Trichuris trichiura infection in Asia at the country and region level. Multiple databases/academic search engines (Web of Science, PubMed, ProQuest, Scopus, and Google Scholar) were searched for literature on T. trichiura prevalence in Asia published through January 2021. Pooled prevalence was determined using the meta-package in R (version 3.6.1). Out of 13,836 articles, 226 studies (5,439,500 individuals) from 26 countries met the inclusion criteria. Of the 226 studies, 151 were community-based studies that included individuals across the age spectrum, while 75 studies focused on school children (typically in the 5-16 years age range). The overall T. trichiura pooled prevalence was 15.3% (95% CI: 12.4-19.1%), with a pooled prevalence of 13.3% (95% CI: 10.0-17.1%) for the community studies and 20.9% (95% CI: 14.7-27.9%) for the studies only including school children. For studies including all age groups, individuals in the 1-15 years age group had the highest pooled prevalence at 23.4% (95% CI: 1.7-49.4%). There was a significant difference found in overall pooled prevalence by sex (p < 0.001) and community type (rural versus urban) (p < 0.001). Although prevalence appears to be decreasing, study findings suggest that T. trichiura infection continues to be a public health problem in Asia. Therefore, control programs focused on at-risk individuals in endemic areas are needed.


Subject(s)
Ascariasis , Helminthiasis , Trichuriasis , Adolescent , Animals , Ascariasis/epidemiology , Ascaris lumbricoides , Asia , Child , Child, Preschool , Feces , Helminthiasis/epidemiology , Humans , Infant , Prevalence , Sanitation , Soil , Trichuriasis/epidemiology , Trichuris
9.
Intern Med ; 61(6): 821-825, 2022 Mar 15.
Article in English | MEDLINE | ID: mdl-34471029

ABSTRACT

Although trichuriasis, a zoonotic disease, has recently become rare in Japan due to improved environmental hygiene, we herein report a 79-year-old man in whom a worm was incidentally found in the ascending colon during colonoscopy for positive fecal occult blood and was endoscopically removed. A genetic analysis identified the worm as Trichuris trichiura possessing mixed sequences from non-human primate and human origins. Despite controversy regarding Trichuris trichiura infection originating from Japanese macaques, according to some studies, it originates primarily from humans. This report suggests the efficacy of a genetic analysis for identifying infection sources.


Subject(s)
Trichuriasis , Trichuris , Animals , Colon, Ascending , Colonoscopy , Humans , Trichuriasis/diagnosis , Trichuris/genetics , Zoonoses
10.
Pediatr Clin North Am ; 69(1): 129-139, 2022 02.
Article in English | MEDLINE | ID: mdl-34794670

ABSTRACT

Intestinal nematode infections caused by soil-transmitted helminths (STH), such as the roundworm Ascaris lumbricoides, the whipworm Trichuris trichiura, and the hookworms Ancylostoma duodenale, and Necator americanus, infect more than 1 billion people throughout the world. School-aged children tend to harbor the greatest numbers of intestinal worms, and as a result, experience more adverse health consequences, such as poor growth, anemia, and cognitive decline. Clinicians should maintain a high degree of suspicion in endemic areas when patients present with surgical abdomens, particularly children. Current antihelminthic drugs are moderately effective, but reinfection is possible. Global efforts are needed to eradicate STH infections.


Subject(s)
Nematode Infections/drug therapy , Nematode Infections/epidemiology , Adolescent , Albendazole/therapeutic use , Ancylostoma/isolation & purification , Anemia/parasitology , Animals , Anthelmintics/therapeutic use , Ascariasis/epidemiology , Ascaris lumbricoides/isolation & purification , Child , Child, Preschool , Female , Helminthiasis/epidemiology , Hookworm Infections/epidemiology , Humans , Hygiene , Infant , Intestinal Diseases, Parasitic/epidemiology , Male , Necator americanus/isolation & purification , Nematode Infections/diagnosis , Nematode Infections/prevention & control , Soil/parasitology , Trichuriasis/epidemiology , Trichuris/isolation & purification
11.
Autops Case Rep ; 11: e2021314, 2021.
Article in English | MEDLINE | ID: mdl-34458182

ABSTRACT

Blood transfusion for chronic anemia can lead to acute or decompensated heart failure in patients who have fluid overload as part of their compensatory response and/or have intrinsic heart disease, and then it could be fatal in such clinical scenarios. This is the report of a case of profound chronic anemia in a young male patient, who was not transfused and then developed confusion followed by terminal cardiopulmonary arrest. Autopsy revealed severe trichuriasis to be the cause of the anemia, along with severe ascariasis, but minimal intrinsic brain disease. This supports the conclusion that anemia was the cause of the confusion, and the lesson that confusion may be a sign that the benefit of blood transfusion outweighs the risk in a patient with severe chronic anemia.

12.
Parasitology ; : 1-12, 2021 Mar 24.
Article in English | MEDLINE | ID: mdl-33757603

ABSTRACT

Trichuriasis known as whipworm infection caused by Trichuris trichiura, is a highly prevalent soil-transmitted helminthiasis in low- and middle-income countries located in tropical and subtropical areas and affecting approximately 360 million people. Children typically harbour the largest burden of T. trichiura and they are usually co-infected with other soil-transmitted helminth (STH), including Ascaris lumbricoides and hookworm. The consequences of trichuriasis, such as malnutrition and physical and cognitive growth restriction, lead to a massive health burden in endemic regions. Despite the implementation of mass drug administration of anthelminthic treatment to school-age children, T. trichiura infection remains challenging to control due to the low efficacy of current drugs as well as high rates of post-treatment re-infection. Thus, the development of a vaccine that would induce protective immunity and reduce infection rate or community faecal egg output is essential. Hurdles for human whipworm vaccine development include the lack of suitable vaccine antigen targets and animal models for human T. trichiura infection. Instead, rodent whipworm T. muris infected mouse models serve as a major surrogate for testing immunogenicity and efficacy of vaccine candidates. In this review, we summarize recent advances in animal models for T. trichiura antigen discovery and testing of vaccine candidates, while providing an overall view of the current status of T. trichiura vaccine development.

13.
Korean J Parasitol ; 59(6): 607-613, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34974667

ABSTRACT

Soil-transmitted helminth (STH) infections are still a considerable challenge in Myanmar. We undertook a control program for STH infections (especially Trichuris trichiura) among schoolchildren in Myanmar using mass drug administration (MDA) and health education. Around 1,700 schoolchildren from 15 primary schools in 3 suburban districts (Shwe Pyi Thar, Twantay, and Kyauktan) of the Yangon Region were subjected in this study during 2017-2019. All of the schoolchildren in each school were orally administered albendazole (400 mg in a single dose) 2, 3, and 4 times a year in 2017, 2018, and 2019, respectively. The results revealed that the egg positive rate of any intestinal helminths (including STH) was reduced from 37.6% (649/1,724) in 2017 to 22.8% (352/1,542) in 2019. The egg positive rate of Ascaris lumbricoides was decreased remarkably from 23.3% (402/1,724) in 2017 to 3.6% (56/1,542) in 2019. However, that of T. trichiura was only slightly reduced from 26.9% (464/1,724) in 2017 to 20.2% (312/1,542) in 2019. The intensity of infection with A. lumbricoides and T. trichiura was both more or less reduced, and the proportion of light infection cases with A. lumbricoides and T. trichiura increased from 35.6% in 2017 to 64.3% in 2019 and from 70.3% in 2017 to 81.7% in 2019, respectively. The results indicated that repeated MDAs (2-4 times a year for 3 years) using albendazole on schoolchildren in Myanmar failed to control T. trichiura infection. For a successful control of trichuriasis in Myanmar, new MDA strategies, using a modified albendazole regimen (multiple daily doses for 2 or 3 days) or an alternative anthelmintic drug, such as oxantel pamoate, is strongly recommended.


Subject(s)
Anthelmintics , Ascariasis , Trichuriasis , Albendazole/therapeutic use , Animals , Anthelmintics/therapeutic use , Ascariasis/drug therapy , Ascariasis/epidemiology , Ascaris lumbricoides , Feces , Mass Drug Administration , Myanmar/epidemiology , Soil , Trichuriasis/drug therapy , Trichuriasis/epidemiology , Trichuris
14.
Autops. Case Rep ; 11: e2021314, 2021. graf
Article in English | LILACS | ID: biblio-1285390

ABSTRACT

Blood transfusion for chronic anemia can lead to acute or decompensated heart failure in patients who have fluid overload as part of their compensatory response and/or have intrinsic heart disease, and then it could be fatal in such clinical scenarios. This is the report of a case of profound chronic anemia in a young male patient, who was not transfused and then developed confusion followed by terminal cardiopulmonary arrest. Autopsy revealed severe trichuriasis to be the cause of the anemia, along with severe ascariasis, but minimal intrinsic brain disease. This supports the conclusion that anemia was the cause of the confusion, and the lesson that confusion may be a sign that the benefit of blood transfusion outweighs the risk in a patient with severe chronic anemia.


Subject(s)
Humans , Male , Adult , Ascariasis/complications , Trichuriasis/complications , Blood Transfusion , Anemia , Autopsy , Heart Diseases
15.
Parasit Vectors ; 13(1): 552, 2020 Nov 07.
Article in English | MEDLINE | ID: mdl-33160406

ABSTRACT

BACKGROUND: Trichuris trichiura (human whipworm) infects an estimated 477 million individuals worldwide. In addition to T. trichiura, other Trichuris species can cause an uncommon zoonosis and a number of human cases have been reported. The diagnosis of trichuriasis has relied traditionally on microscopy. Recently, there is an effort to use molecular diagnostic methods, mainly qPCR. LAMP technology could be an alternative for qPCR especially in low-income endemic areas. Trichuris muris, the causative agent of trichuriasis in mice, is of great importance as a model for human trichuriasis. Here, we evaluate the diagnostic utility of a new LAMP assay in an active experimental mouse trichuriasis in parallel with parasitological method by using stool and, for the first time, urine samples. METHODS: Stool and urine samples were collected from mice infected with eggs of T. muris. The dynamics of infection was determined by counting the number of eggs per gram of faeces. A LAMP based on the 18S rRNA gene from T. muris was designed. Sensitivity and specificity of LAMP was tested and compared with PCR. Stool and urine samples were analysed by both LAMP and PCR techniques. RESULTS: Trichuris muris eggs were detected for the first time in faeces 35 days post-infection. LAMP resulted specific and no cross-reactions were found when using 18 DNA samples from different parasites. The detection limit of the LAMP assay was 2 pg of T. muris DNA. When testing stool samples by LAMP we obtained positive results on day 35 p.i. and urine samples showed amplification results on day 20 p.i., i.e. 15 days before the onset of T. muris eggs in faeces. CONCLUSIONS: To the best of our knowledge, we report, for the first time, a novel LAMP assay (Whip-LAMP) for sensitive detection of T. muris DNA in both stool and urine samples in a well-established mice experimental infection model. Considering the advantages of urine in molecular diagnosis in comparison to stool samples, should make us consider the possibility of starting the use urine specimens in molecular diagnosis and for field-based studies of human trichuriasis where possible. Further studies with clinical samples are still needed.


Subject(s)
DNA, Helminth/isolation & purification , Feces/parasitology , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , Trichuriasis/diagnosis , Trichuris/genetics , Animals , Disease Models, Animal , Female , Mice , Parasite Egg Count , Specific Pathogen-Free Organisms , Trichuriasis/urine
16.
J Parasitol ; 106(5): 603-610, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32997756

ABSTRACT

Trichuriasis is a serious threat to the economic development of animal husbandry. This research aimed to establish a droplet digital PCR (ddPCR) method to detect Trichuris spp. for the early diagnosis and prevention of trichuriasis in sheep. The real-time quantitative PCR (qPCR) and ddPCR methods were used for the detection of nematodes by targeted amplification of the ITS gene. Each means was evaluated to optimize the limit of detection and reproducibility. For a recombinant plasmid, the qPCR results showed that the detection limit was 31.7 copies per reaction. In contrast to qPCR, ddPCR was able to detect concentrations below 3.17 copies per reaction. Both assays exhibited good reproducibility. However, the ddPCR method was more stable for low-copy-number detection. This new assay was specific for Trichuris spp. and did not cross-react with other relevant gastrointestinal nematodes. A total of 98 clinical samples were tested with both assays. The results showed that the positive rate of ddPCR (80.6%) was higher than that of qPCR (72.4%). This method could be used as an efficient molecular biology tool to test for Trichuris spp. and could be a new valuable tool for the clinical diagnosis and prevention of trichuriasis.


Subject(s)
Polymerase Chain Reaction/veterinary , Sheep Diseases/diagnosis , Trichuriasis/veterinary , Animals , DNA, Helminth/isolation & purification , Feces/parasitology , Polymerase Chain Reaction/methods , Polymerase Chain Reaction/standards , Real-Time Polymerase Chain Reaction/standards , Real-Time Polymerase Chain Reaction/veterinary , Reproducibility of Results , Sensitivity and Specificity , Sheep , Sheep Diseases/parasitology , Sheep Diseases/prevention & control , Trichuriasis/diagnosis , Trichuriasis/prevention & control
18.
J Helminthol ; 94: e142, 2020 Apr 02.
Article in English | MEDLINE | ID: mdl-32238209

ABSTRACT

Whipworm infection or trichuriasis caused by Trichuris trichiura is of major public health concern in sub-Saharan Africa, particularly among pre-school and school-going children. It is among the neglected tropical diseases targeted for elimination through mass drug administration (MDA). One of the outcomes of MDA is a rapid decline in levels of infection intensity, making it difficult to monitor effectiveness of control measures using the conventional Kato-Katz procedure, which relies on the microscopic detection of parasite ova in faecal samples. In the present study, a loop-mediated isothermal amplification (LAMP) test was developed for the detection of T. trichiura infection in faecal samples. LAMP technology offers greater sensitivity and specificity than the microscopy-based tests. A set of four specific primers targeting the internal transcribed spacer 2 region of the ribosomal DNA were designed using Primer Explorer software. DNA was extracted from faecal samples using the alkaline lysis method (HotSHOT) and the LAMP reaction performed at 63°C for 1 h. The amplicons were visualized by both gel electrophoresis and with the naked eye following staining with SYBR green dye. Sensitivity and specificity tests were determined using the standard Kato-Katz diagnostic procedure as a reference test. The developed LAMP assay reliably detected T. trichiura DNA in faecal samples, with a specificity and sensitivity of 88% and 77%, respectively. No cross-reactivity was observed with several common helminth parasites. The developed LAMP assay is an appropriate diagnostic method for the detection of T. trichiura DNA in human faecal samples due to its simplicity, low cost, high sensitivity and specificity.


Subject(s)
Feces/parasitology , Nucleic Acid Amplification Techniques/methods , Temperature , Trichuriasis/diagnosis , Animals , Child , DNA Primers/genetics , DNA, Helminth/genetics , DNA, Ribosomal/genetics , Humans , Sensitivity and Specificity , Trichuris/isolation & purification
19.
Parasit Vectors ; 13(1): 109, 2020 Feb 28.
Article in English | MEDLINE | ID: mdl-32111243

ABSTRACT

BACKGROUND: Schistosomiasis continues to inflict significant morbidity and mortality in the tropical and subtropical regions of the world. The disease endemicity overlaps with the transmission of other parasitic diseases. Despite the ubiquity of polyparasitism in tropical regions, particularly in rural communities, little is known about the impact of multiple helminth infections on disease progression. In this pilot study, we describe the influence of chronic Trichuris trichiura infection on Schistosoma mansoni egg-induced hepatopathology in infected baboons. METHODS: Baboons with or without underlying whipworm infection were challenged with S. mansoni cercariae to establish schistosomiasis. Adult S. mansoni worms were recovered by perfusion and enumerated, hepatic granulomas were quantified via light microscopy, and transcriptional profiling of tissues were completed using RNA sequencing technologies. RESULTS: Co-infection with both S. mansoni and T. trichiura resulted in higher female schistosome worm burden and significantly larger liver granuloma sizes. Systems biology analyses of peripheral blood mononuclear cells (PBMC) revealed pathways associated with increased liver damage in co-infected baboons. CONCLUSIONS: Underlying chronic whipworm infection intensified schistosome egg-induced liver pathology in infected baboons. RNA-Seq analysis provided insight into pathways associated with increased liver damage, corroborating histological findings.


Subject(s)
Coinfection/pathology , Coinfection/veterinary , Liver Diseases, Parasitic/pathology , Liver Diseases, Parasitic/veterinary , Schistosomiasis/pathology , Schistosomiasis/veterinary , Trichuriasis/pathology , Trichuriasis/veterinary , Animal Diseases/parasitology , Animal Diseases/pathology , Animals , Chronic Disease , Coinfection/parasitology , Female , Granuloma/pathology , Humans , Liver/metabolism , Liver/parasitology , Liver/pathology , Liver Diseases, Parasitic/parasitology , Male , Papio , Parasite Egg Count , Pilot Projects , Primates , Schistosoma mansoni , Schistosomiasis/parasitology , Transcriptome , Trichuriasis/parasitology , Trichuris
20.
Clin Infect Dis ; 70(6): 1193-1201, 2020 03 03.
Article in English | MEDLINE | ID: mdl-31044235

ABSTRACT

BACKGROUND: Preventive chemotherapy is the main strategy to control soil-transmitted helminth (STH) infections. Albendazole and mebendazole are ubiquitously used, but they are not sufficiently effective against Trichuris trichiura. Moxidectin might be a useful addition to the small drug armamentarium. However, the optimal dosage of moxidectin alone and in combination with albendazole against T. trichiura and other STHs has not yet been determined. METHODS: A Phase II, randomized, placebo-controlled, dose-finding trial was conducted in 2 secondary schools on Pemba Island, Tanzania. Using a computer-generated list, T. trichiura-infected adolescents were randomly assigned to 7 treatment arms: 8, 16, or 24 mg of moxidectin monotherapy; 8, 16, or 24 mg of moxidectin plus 400 mg of albendazole combination therapy; or placebo. The primary outcome was cure rate (CR) against T. trichiura, analyzed 13 to 20 days after treatment by quadruple Kato-Katz thick smears. RESULTS: A total of 290 adolescents were enrolled (41 or 42 per arm). CRs against T. trichiura were 43, 46, and 44% for 8, 16, and 24 mg of moxidectin alone, respectively; 60, 62, and 66% for the same moxidectin dosages plus 400 mg of albendazole, respectively; and 12% for placebo. The moxidectin-albendazole arms also revealed higher CRs and egg reduction rates against hookworm than the monotherapy arms. Moxidectin and its combination with albendazole were well tolerated. CONCLUSIONS: Moxidectin-albendazole is superior to moxidectin. There is no benefit of using doses above 8 mg, which is the recommended dose for onchocerciasis. The moxidectin-albendazole combination of 8 mg plus 400 mg should be investigated further to develop recommendations for appropriate control of STH infections. CLINICAL TRIALS REGISTRATION: NCT03501251.


Subject(s)
Anthelmintics , Trichuriasis , Adolescent , Albendazole/adverse effects , Animals , Anthelmintics/adverse effects , Feces , Humans , Macrolides , Tanzania , Trichuriasis/drug therapy , Trichuris
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