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Ranasinghe S, Aspinall S, Beynon A, Ash A, Lymbery A. Traditional medicinal plants in the treatment of gastrointestinal parasites in humans: A systematic review and meta-analysis of clinical and experimental evidence. Phytother Res 2023; 37:3675-3687. [PMID: 37230485 DOI: 10.1002/ptr.7895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/22/2023] [Accepted: 05/09/2023] [Indexed: 05/27/2023]
Abstract
Gastrointestinal (GI) parasites cause significant morbidity and mortality worldwide. The use of conventional antiparasitic drugs is often inhibited due to limited availability, side effects or parasite resistance. Medicinal plants can be used as alternatives or adjuncts to current antiparasitic therapies. This systematic review and meta-analysis aimed to critically synthesise the literature on the efficacy of different plants and plant compounds against common human GI parasites and their toxicity profiles. Searches were conducted from inception to September 2021. Of 5393 screened articles, 162 were included in the qualitative synthesis (159 experimental studies and three randomised control trials [RCTs]), and three articles were included in meta-analyses. A total of 507 plant species belonging to 126 families were tested against different parasites, and most of these (78.4%) evaluated antiparasitic efficacy in vitro. A total of 91 plant species and 34 compounds were reported as having significant in vitro efficacy against parasites. Only a few plants (n = 57) were evaluated for their toxicity before testing their antiparasitic effects. The meta-analyses revealed strong evidence of the effectiveness of Lepidium virginicum L. against Entamoeba histolytica with a pooled mean IC50 of 198.63 μg/mL (95% CI 155.54-241.72). We present summary tables and various recommendations to direct future research.
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Affiliation(s)
- Sandamalie Ranasinghe
- Centre for Biosecurity and One Health, Harry Butler Institute, Murdoch University, Perth, Western Australia, Australia
| | - Sasha Aspinall
- School of Allied Health, College of Health and Education, Murdoch University, Perth, Western Australia, Australia
| | - Amber Beynon
- Department of Chiropractic, Faculty of Medicine, Health and Human Sciences, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Amanda Ash
- Centre for Biosecurity and One Health, Harry Butler Institute, Murdoch University, Perth, Western Australia, Australia
| | - Alan Lymbery
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, Perth, Western Australia, Australia
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Intestinal Helminth Infections in Ghanaian Children from the Ashanti Region between 2007 and 2008—A Retrospective Cross-Sectional Real-Time PCR-Based Assessment. Trop Med Infect Dis 2022; 7:tropicalmed7110374. [DOI: 10.3390/tropicalmed7110374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 10/18/2022] [Accepted: 11/12/2022] [Indexed: 11/16/2022] Open
Abstract
In spite of ongoing eradication programs, helminth infections are still a medical issue in Ghana. For follow-up assessments on the decline of regional helminth infections, historic baseline prevalence values obtained with standardized diagnostic procedures can be helpful. In this retrospective cross-sectional study, real-time PCR targeting the nematodes Ancylostoma spp. (ITS2), Ascaris lumbricoides (ITS1), Enterobius vermicularis (ITS1), Necator americanus (ITS2), Strongyloides stercoralis (18S rRNA) and Trichuris trichiura (18S rRNA), the trematodes Schistosoma spp. (ITS2) as well as the cestodes Hymenolepis nana (ITS1), Taenia saginata (ITS1) and Taenia solium (ITS1) was applied with 2046 DNA eluates from stool samples of Ghanaian children from the Ashanti region collected between 2007 and 2008 in order to retrospectively define prevalence values. The overall prevalence was low with 3.8% (n = 77) and only 0.1% (n = 2) double infections with helminths were recorded. The three most frequently detected enteric helminth species comprised 2% S. stercoralis (n = 41), 0.8% H. nana (n = 16), and 0.7% N. americanus (n = 14), while only sporadic infection events were recorded for other helminth species comprising 0.1% E. vermicularis (n = 2), 0.1% Schistosoma spp. (n = 2), 0.1% T. saginata (n = 1) and 0.1% T. trichiura (n = 1). A. lumbricoides, Ancylostoma spp. and T. solium were not detected at all. In conclusion, the retrospective assessment suggests a low prevalence of enteric helminth infections in Ghanaian children from the Ashanti Region within the assessment period between 2007 and 2008.
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Ellwanger JH, Ziliotto M, Kulmann-Leal B, Chies JAB. Iron deficiency and soil-transmitted helminth infection: classic and neglected connections. Parasitol Res 2022; 121:3381-3392. [PMID: 36258094 DOI: 10.1007/s00436-022-07697-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/14/2022] [Indexed: 10/24/2022]
Abstract
Beyond participating in the oxygen transport by red blood cells, iron is an essential micronutrient and contributes to different physiological pathways and processes, such as cell proliferation, DNA repair, and other homeostatic functions. Iron deficiency affects millions of people, especially children and pregnant women. The consequences of iron deficiency are diverse, including inadequate child development, impaired cognition, and reduced productivity. Several factors contribute to iron deficiency, such as iron-poor diet, genetic factors, and infection with soil-transmitted helminths (STHs), especially roundworms (Ascaris lumbricoides), hookworms (Necator americanus and Ancylostoma duodenale), and whipworms (Trichuris trichiura). This review updates and summarizes the role of STHs as drivers of iron deficiency. Also, the poorly explored connections between STH infection, geophagia (a pica manifestation), immune response, and iron deficiency are discussed, highlighting how iron deficiency may act as a risk factor for infections by STHs, in addition to being a consequence of intestinal parasitic infections. Finally, strategies for control and management of iron deficiency and STH infection are described.
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Affiliation(s)
- Joel Henrique Ellwanger
- Laboratory of Immunobiology and Immunogenetics (Prédio 43323, Laboratório 212), Department of Genetics, Postgraduate Program in Genetics and Molecular Biology (PPGBM), Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, Campus do Vale, Rio Grande do Sul, Porto Alegre, Brazil.
| | - Marina Ziliotto
- Laboratory of Immunobiology and Immunogenetics (Prédio 43323, Laboratório 212), Department of Genetics, Postgraduate Program in Genetics and Molecular Biology (PPGBM), Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, Campus do Vale, Rio Grande do Sul, Porto Alegre, Brazil
| | - Bruna Kulmann-Leal
- Laboratory of Immunobiology and Immunogenetics (Prédio 43323, Laboratório 212), Department of Genetics, Postgraduate Program in Genetics and Molecular Biology (PPGBM), Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, Campus do Vale, Rio Grande do Sul, Porto Alegre, Brazil
| | - José Artur Bogo Chies
- Laboratory of Immunobiology and Immunogenetics (Prédio 43323, Laboratório 212), Department of Genetics, Postgraduate Program in Genetics and Molecular Biology (PPGBM), Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, Campus do Vale, Rio Grande do Sul, Porto Alegre, Brazil
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Prevalence and intensity of soil-transmitted helminth infections and associated risk factors among household heads living in the peri-urban areas of Jimma town, Oromia, Ethiopia: A community-based cross-sectional study. PLoS One 2022; 17:e0274702. [PMID: 36107925 PMCID: PMC9477373 DOI: 10.1371/journal.pone.0274702] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 09/02/2022] [Indexed: 11/29/2022] Open
Abstract
Background Ethiopia has set national targets for eliminating soil-transmitted helminths (STH) as public health problems by 2020 and for breaking their transmission by 2025 using periodic mass treatment of children in endemic areas. However, the status of STH infection among the adults living in the same communities remains unknown. The aim of this study, therefore, was to determine the prevalence and intensity of STH infections and associated factors among the household heads in the peri-urban areas of Jimma town, Oromia, Ethiopia. Methods A community-based cross-sectional study was conducted in five peri-urban kebeles (smallest administrative unit in Ethiopia) of Jimma town from May to July 2021. A semi-structured questionnaire was used to collect data on socio-demographic and predisposing factors. The Kato-Katz concentration technique was utilized to detect and quantify the STH in stool samples. Both bivariate and multivariate analyses were done. P-value <0.05 was considered statistically significant. Results A total of 376 household heads (19.9% women and 80.1% men) from peri-urban areas were included in the study. The overall STH prevalence was 18.1% (95% CI: 14.6–22.1) with A. lumbricoides being the predominant species (11.4%) followed by T. trichiura (7.2%) and hookworm (2.1%). Most of the STH positive household heads had single infections (85.3%) and light-intensity infections (88.5%). Wealth status (AOR = 2.7; 95% CI: 1.31–5.50, P = 0.007), hand washing habits before meals (AOR = 7.07; 95% CI: 1.79–27.88, p = 0.005), fingernails status (AOR = 2.99; 95% CI: 1.59–5.65, p = 0.001), and toilet facility type (AOR = 2.06; 95% CI: 1.13–3.76, p = 0.017) were found to have statistically significant associations with the STH infection. Conclusion The findings of this study showed a nearly moderate level of STH prevalence among household heads in the peri-urban community. This could serve as an important reservoir for reinfection of the treated children and other at-risk groups in the community.
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Wu Y, Li E, Knight M, Adeniyi-Ipadeola G, Song LZ, Burns AR, Gazzinelli-Guimaraes AC, Fujiwara R, Bottazzi ME, Weatherhead JE. Transient Ascaris suum larval migration induces intractable chronic pulmonary disease and anemia in mice. PLoS Negl Trop Dis 2021; 15:e0010050. [PMID: 34914687 PMCID: PMC8717995 DOI: 10.1371/journal.pntd.0010050] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 12/30/2021] [Accepted: 12/03/2021] [Indexed: 12/13/2022] Open
Abstract
Ascariasis is one of the most common infections in the world and associated with significant global morbidity. Ascaris larval migration through the host’s lungs is essential for larval development but leads to an exaggerated type-2 host immune response manifesting clinically as acute allergic airway disease. However, whether Ascaris larval migration can subsequently lead to chronic lung diseases remains unknown. Here, we demonstrate that a single episode of Ascaris larval migration through the host lungs induces a chronic pulmonary syndrome of type-2 inflammatory pathology and emphysema accompanied by pulmonary hemorrhage and chronic anemia in a mouse model. Our results reveal that a single episode of Ascaris larval migration through the host lungs leads to permanent lung damage with systemic effects. Remote episodes of ascariasis may drive non-communicable lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), and chronic anemia in parasite endemic regions. Ascariasis is the most common helminth infection and leads to significant global morbidity. Transient Ascaris larval migration through the host’s lungs is essential for larval development but leads to an exaggerated type-2 host immune response. Our work demonstrates that transient Ascaris spp. larval migration through the lungs has significant long-term consequences including changes in lung structure and function as well as vascular damage causing chronic lung disease and anemia. We propose that Ascaris spp. larval migration through the host lungs is a risk factor for the development of chronic lung disease and anemia in parasite-endemic regions globally.
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Affiliation(s)
- Yifan Wu
- Department of Pediatrics, Pediatric Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Medicine, Pathology and Immunology, and the Biology of Inflammation Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Evan Li
- Department of Medicine, Pathology and Immunology, and the Biology of Inflammation Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Morgan Knight
- Department of Medicine, Pathology and Immunology, and the Biology of Inflammation Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Grace Adeniyi-Ipadeola
- Department of Pediatrics, Pediatric Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
| | - Li-zhen Song
- Department of Medicine, Pathology and Immunology, and the Biology of Inflammation Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Alan R. Burns
- College of Optometry, University of Houston, Houston, Texas, United States of America
| | | | - Ricardo Fujiwara
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Maria Elena Bottazzi
- Department of Pediatrics, Pediatric Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- Texas Children’s Hospital Center for Vaccine Development, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jill E. Weatherhead
- Department of Pediatrics, Pediatric Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Medicine, Infectious Diseases, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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Farrant O, Marlais T, Houghton J, Goncalves A, Teixeira da Silva Cassama E, Cabral MG, Nakutum J, Manjuba C, Rodrigues A, Mabey D, Bailey R, Last A. Prevalence, risk factors and health consequences of soil-transmitted helminth infection on the Bijagos Islands, Guinea Bissau: A community-wide cross-sectional study. PLoS Negl Trop Dis 2020; 14:e0008938. [PMID: 33326420 PMCID: PMC7773412 DOI: 10.1371/journal.pntd.0008938] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 12/30/2020] [Accepted: 10/30/2020] [Indexed: 11/19/2022] Open
Abstract
Soil-transmitted helminths (STH) are endemic and widespread across Sub-Saharan Africa. A community wide soil-transmitted helminth (STH) prevalence survey was performed on the island of Bubaque in Guinea-Bissau using both Kato-katz microscopy and qPCR methodology. Predictors of infection and morbidity indicators were identified using multivariable logistic regression, and diagnostic methods were compared using k statistics. Among 396 participants, prevalence of STH by microscopy was 23.2%, hookworm was the only species identified by this method and the mean infection intensity was 312 eggs per gram. qPCR analysis revealed an overall prevalence of any STH infection of 47.3%, with the majority A. duodenale (32.3%), followed by N. americanus (15.01%) and S. stercoralis (13.2%). A. lumbricoides, and T. trichiura infections were negligible, with a prevalence of 0.25% each. Agreement between diagnostic tests was k = 0.22, interpreted as fair agreement, and infection intensity measured by both methods was only minimally correlated (Rs = -0.03). STH infection overall was more common in females and adults aged 31-40. STH infection was associated with open defaecation, low socio-economic status and further distance to a water-source. The prevalence of anaemia (defined as a binary outcome by the WHO standards for age and sex) was 69.1%, and 44.2% of children were malnourished according to WHO child growth standards. Hookworm infection intensity by faecal egg count showed no statistically significant association with age (Rs 0.06) but S. Stercoralis infection intensity by qPCR cycle threshold was higher in pre-school aged children (Rs = 0.30, p-value 0.03) There was no statistically significant association between STH infection and anaemia (OR 1.0 p = 0.8), stunting (OR 1.9, p-value 0.5) and wasting (OR 2.0, p-value 0.2) in children. This study reveals a persistent reservoir of STH infection across the community, with high rates of anaemia and malnutrition, despite high-coverage of mebendazole mass-drug administration in pre-school children. This reflects the need for a new strategy to soil-transmitted helminth control, to reduce infections and ultimately eliminate transmission.
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Affiliation(s)
- Olivia Farrant
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Tegwen Marlais
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Joanna Houghton
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Adriana Goncalves
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Jose Nakutum
- Region Sanitaria Bolama-Bijagós, Bubaque, Guinea Bissau
| | | | | | - David Mabey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Robin Bailey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anna Last
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Miller MM, Reinhardt RL. The Heterogeneity, Origins, and Impact of Migratory iILC2 Cells in Anti-helminth Immunity. Front Immunol 2020; 11:1594. [PMID: 32793230 PMCID: PMC7390839 DOI: 10.3389/fimmu.2020.01594] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 06/16/2020] [Indexed: 12/12/2022] Open
Abstract
Soil-transmitted helminths represent a major global health burden with infections and infection-related comorbidities causing significant reductions in the quality of life for individuals living in endemic areas. Repeated infections and chronic colonization by these large extracellular worms in mammals led to the evolution of type-2 immunity characterized by the production of the type-2 cytokines interleukin (IL)-4, IL-5, and IL-13. Although a number of adaptive and innate immune cells produce type-2 cytokines, a key cellular source in the context of helminth infection is group 2 innate lymphoid cells (ILC2s). ILC2s promote mucosal barrier homeostasis, integrity, and repair by rapidly responding to epithelial cues in mucosal tissues. Though tissue-resident ILC2s (nILC2s) have been studied in detail over the last decade, considerably less is known with regard to a subset of inflammatory ILC2s (iILC2s) that migrate to the lungs of mice early after Nippostrongylus brasiliensis infection and are potent early producers of type-2 cytokines. This review will discuss the relationship and differences between nILC2s and iILC2s that establish their unique roles in anti-helminth immunity. We have placed particular emphasis on studies investigating iILC2 origin, function, and their potential long-term contribution to tissue-resident ILC2 reservoirs in settings of helminth infection.
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Affiliation(s)
- Mindy M Miller
- Department of Biomedical Research, National Jewish Health, Denver, CO, United States
| | - R Lee Reinhardt
- Department of Biomedical Research, National Jewish Health, Denver, CO, United States.,Department of Immunology and Microbiology, University of Colorado-Anschutz Medical, Aurora, CO, United States
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Nasr NA, Al-Mekhlafi HM, Lim YAL, Elyana FN, Sady H, Atroosh WM, Dawaki S, Al-Delaimy AK, Al-Areeqi MA, Wehaish AA, Anuar TS, Mahmud R. A holistic approach is needed to control the perpetual burden of soil-transmitted helminth infections among indigenous schoolchildren in Malaysia. Pathog Glob Health 2020; 114:145-159. [PMID: 32249689 PMCID: PMC7241489 DOI: 10.1080/20477724.2020.1747855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
A cross-sectional survey was conducted among 1,142 Orang Ali schoolchildren in six states of Peninsular Malaysia to investigate the current prevalence and risk factors of STH infections. Faecal samples were examined using direct smear, formalin-ether sedimentation, Kato-Katz, and Harada-Mori methods. A pre-tested questionnaire was used to collect information on the demographic, socioeconomic, personal hygiene, and health status of the participants. Overall, 70.1% (95% CI = 67.4, 72.7) of the participants were infected with at least one of the STH species. The prevalence of Ascaris lumbricoides, Trichuris trichiura, and hookworm infections was 63.1%, 61.8% and 11.5%, respectively. Moderate-to-heavy STH infections accounted for 61.3% of the total infections. Univariate and logistic regression analyses revealed different sets of risk factors, with age (> 10 years) being the significant risk factor of all three STH species. Moreover, other species-specific risk factors were identified including being a member of the Senoi tribe, family size (≥ 7 members), school size (150-250 pupils), maternal unemployment, unimproved source of drinking water, lacking improved toilet in the house, inadequate WASH facilities at school, not washing hands before eating, and not washing fruits before eating; presence of domestic animals, and not wearing shoes when outside. The high prevalence of STH infections found in the study population exceeds the WHO policy intervention threshold (20% prevalence). Thus, an innovative holistic approach should be adopted to control STH infections among these children as part of the efforts to improve the quality of life of the entire Orang Asli population. .
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Affiliation(s)
- Nabil A. Nasr
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hesham M. Al-Mekhlafi
- Medical Research Centre, Jazan University, Jazan, Kingdom of Saudi Arabia
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Yvonne A. L. Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Fatin Nur Elyana
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hany Sady
- Department of Medical Laboratories, Faculty of Medical Sciences, Hodeidah University, Hodeidah, Yemen
| | - Wahib M. Atroosh
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Microbiology and Parasitology, Faculty of Medicine and Health Sciences, University of Aden, Aden, Yemen
| | - Salwa Dawaki
- School of Health Technology, Nassarawa, Kano, Nigeria
| | - Ahmed K. Al-Delaimy
- Department of Family and Community Medicine, College of Medicine, University of Anbar, Ramadi, Iraq
| | - Mona A. Al-Areeqi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Abkar A. Wehaish
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Tengku Shahrul Anuar
- Centre of Medical Laboratory Technology, Faculty of Health Sciences, Universiti Teknologi MARA, Selangor, Malaysia
- Integrative Pharmacogenomics Institute, Universiti Teknologi MARA, Selangor, Malaysia
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Dong Y, Zou Z, Hu P, Dong B, Wang Z, Yang Z, Wen B, Ma Y, Song Y, Ma J, Lau PWC. Secular Trends of Ascariasis Infestation and Nutritional Status in Chinese Children From 2000 to 2014: Evidence From 4 Successive National Surveys. Open Forum Infect Dis 2019; 6:ofz193. [PMID: 31139673 PMCID: PMC6527090 DOI: 10.1093/ofid/ofz193] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 04/17/2019] [Indexed: 12/31/2022] Open
Abstract
Background This study aimed to assess secular trends and epidemiological status of ascariasis infestations and to explore its effects on the nutritional transition among Chinese children from 2000 to 2014. Methods Data were collected from 69 435 Chinese children aged 7-year-olds and 9-year-olds in 4 successive cross-sectional surveys of Chinese National Survey on Students’ Constitution and Health. Ascariasis infestation was defined by using the Kato-Katz method. Nutritional status was classified into stunting, thinness, overweight, and obesity by WHO definition. Results From 2000 to 2014, the ascariasis infestation rates decreased from 9.1% to 1.7%, the stunting and thinness prevalence decreased from 4.3% and 13.8% to 0.7% and 7.1%, while the overweight and obesity prevalence increased from 3.6% and 2.1% to 9.8% and 9.1%, respectively. Compared to children in the ascariasis noninfestation group, those infected with ascariasis had a worse nutritional status. Yet, the disparity in nutritional status between 2 groups disappeared over time. Provinces with a higher gross domestic product per capita simultaneously had lower ascariasis infestation rates, lower stunting and thinness prevalence, and higher overweight and obesity prevalence. Conclusions The retardation effects caused by ascariasis infestation on nutritional status in Chinese children seemed to be offset by the rapid economic development and nutritional transition over time; nevertheless, multiple prevention and control measures are still needed and should be continuously strengthened.
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Affiliation(s)
- Yanhui Dong
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Zhiyong Zou
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Peijin Hu
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Bin Dong
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Zhenghe Wang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Zhaogeng Yang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Bo Wen
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Yinghua Ma
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Yi Song
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Jun Ma
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing, China
| | - Patrick W C Lau
- Department of Sport and Physical Education, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
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Seguí R, Muñoz-Antoli C, Klisiowicz DR, Oishi CY, Köster PC, de Lucio A, Hernández-de-Mingo M, Puente P, Toledo R, Esteban JG, Carmena D. Prevalence of intestinal parasites, with emphasis on the molecular epidemiology of Giardia duodenalis and Blastocystis sp., in the Paranaguá Bay, Brazil: a community survey. Parasit Vectors 2018; 11:490. [PMID: 30165880 PMCID: PMC6117969 DOI: 10.1186/s13071-018-3054-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 08/10/2018] [Indexed: 12/22/2022] Open
Abstract
Background Intestinal protozoan parasites are major contributors to the global burden of gastrointestinal disease causing significant socioeconomic consequences. Children living in resource-poor settings with restricted access to water and sanitary services are particularly at risk of these infections. Methods A prospective, community-based, cross-sectional survey was conducted in Paraná (southern Brazil) between May 2015 and May 2016. A total of 766 stool samples were individually collected from volunteers (male/female ratio: 0.99; age range: 0–76 years) and used for investigating the presence of intestinal helminth and protozoan species by routine microscopic procedures including the Kato-Katz and modified Ritchie concentration methods and the Ziehl-Neelsen stain technique. Quantitative real-time PCR confirmed microscopy-positive samples for Giardia duodenalis and the assemblages and sub-assemblages determined by multilocus sequence-based genotyping of the glutamate dehydrogenase (gdh) and β-giardin (bg) genes of the parasite. Identification of Blastocystis subtypes was carried out by amplification and sequencing of a partial fragment of the small-subunit ribosomal RNA gene (SSU rDNA) of this heterokont microorganism. Results Overall, 46.1% (353/766) of the participants were infected/colonised by at least one intestinal parasite/commensal species. Protozoan and helminth species were detected in 42.7% and 10.1% of the surveyed population, respectively. Blastocystis sp. (28.2%), Endolimax nana (14.9%), and Giardia duodenalis (11.0%) were the most prevalent species found among protozoans and Ascaris lumbricoides (5.0%), Trichuris trichiura (4.6%) and hookworms (1.0%) among helminths. A total of 38 G. duodenalis-positive samples were genotyped at gdh and bg markers, revealing the presence of the sub-assemblages AII (47.4%), AII/AIII (2.6%), BIII (5.3%), BIV (26.3%) and BIII/BIV (13.1%). Two samples (5.3%) were only identified as assemblage B. AII was predominantly found in females aged 5–9 years and was associated with a higher likelihood of reporting gastrointestinal symptoms. A total of 102 Blastocystis-positive samples were successfully subtyped at the SSU rRNA gene revealing the presence of ST1 (36.3%), ST2 (15.7%), ST3 (41.2%), ST4 (2.9%), ST6 (1.0%) and ST8 (2.9%). Conclusions Data presented here indicate that enteric parasites still represent a pressing health concern in Paraná, Brazil, probably due to sub-optimal water, sanitation and hygiene conditions. A mostly anthroponotic origin is suspected for G. duodenalis and Blastocystis sp. infections. Electronic supplementary material The online version of this article (10.1186/s13071-018-3054-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Raimundo Seguí
- Department of Pharmacy, Pharmaceutical Technology and Parasitology, Parasitology Area, Faculty of Pharmacy, Valencia University, Avda. Vicent Andrés Estellés s/n, 46100, Burjassot, Valencia, Spain
| | - Carla Muñoz-Antoli
- Department of Pharmacy, Pharmaceutical Technology and Parasitology, Parasitology Area, Faculty of Pharmacy, Valencia University, Avda. Vicent Andrés Estellés s/n, 46100, Burjassot, Valencia, Spain.
| | - Debora R Klisiowicz
- Department of Basic Pathology, Biological Sciences Area, Paraná Federal University, Av. Cel. Francisco H. dos Santos 100, Curitiba, 19031, Brazil
| | - Camila Y Oishi
- Department of Basic Pathology, Biological Sciences Area, Paraná Federal University, Av. Cel. Francisco H. dos Santos 100, Curitiba, 19031, Brazil
| | - Pamela C Köster
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - Aida de Lucio
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - Marta Hernández-de-Mingo
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - Paula Puente
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain
| | - Rafael Toledo
- Department of Pharmacy, Pharmaceutical Technology and Parasitology, Parasitology Area, Faculty of Pharmacy, Valencia University, Avda. Vicent Andrés Estellés s/n, 46100, Burjassot, Valencia, Spain
| | - José G Esteban
- Department of Pharmacy, Pharmaceutical Technology and Parasitology, Parasitology Area, Faculty of Pharmacy, Valencia University, Avda. Vicent Andrés Estellés s/n, 46100, Burjassot, Valencia, Spain
| | - David Carmena
- Parasitology Reference and Research Laboratory, National Centre for Microbiology, Ctra. Majadahonda-Pozuelo Km 2, 28220 Majadahonda, Madrid, Spain.
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Salmon M, Salmon C, Masoda M, Salumu JM, Bozzi C, Nieburg P, Harrison LM, Humphries D, Abaca Uvon N, Wendel SK, Trout C, Cappello M. Albendazole Treatment Improves Work Capacity in Women Smallholder Farmers Infected with Hookworm: A Double-Blind Randomized Control Trial. Am J Trop Med Hyg 2018; 98:1419-1426. [PMID: 29611504 DOI: 10.4269/ajtmh.17-0403] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
An estimated 4.7 billion people live in regions exposed to soil-transmitted helminths, intestinal parasites that have significant impacts on the health of women smallholder farmers. The goal of this trial was to determine whether treatment with albendazole impacts the work capacity of these farmers. This is a prospective double-blind, randomized effectiveness trial. Participants (N = 250) were randomly selected from safe motherhood groups in the Democratic Republic of Congo. Prevalence/intensity of hookworm infection, hemoglobin, and demographics was obtained. At study (Time = 0), participants were randomized into treatment (albendazole 400 mg) and placebo (similar placebo tablet) groups. A step test was administered as a proxy metric for work capacity. Work capacity was defined as ∆heart rate before and after 3 minutes of step testing, in beats per minute. At study (time = 7 months), the step test was repeated and work capacity remeasured. The ∆work capacity (time = 0 minus time = 7 months) was the primary outcome. Investigators/field assistants were blinded to who was enrolled in groups, hookworm status, and step test results. Regression showed highly significant interactive effects of hookworm status and treatment group relative to ∆work capacity after controlling for resting pulse rate and age (P < 0.002). Estimated marginal means for work capacity (WC) for each of four groups (hookworm positive plus placebo, hookworm positive plus treatment, hookworm negative plus placebo, and hookworm negative plus treatment) showed women who were hookworm positive and received treatment decreased heart rate by 9.744 (95% confidence interval [CI]: 6.42, 13.07) beats per minute (increased WC), whereas women who were hookworm positive and received placebo saw a nonsignificant decrease of 0.034 (95% CI: -3.16, 3.84) beats per minute. Treatment with albendazole was associated with improved aerobic work capacity posttreatment. Given modest costs of drug distributions, risk benefits of periodic deworming warrants further study in larger controlled trials.
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Affiliation(s)
- Margaret Salmon
- InnovationCZ, San Francisco, California.,Global Health Emergency Medicine, University Health Network, University of Toronto, Toronto, Canada
| | | | - Maurice Masoda
- Health Education Action Leadership Africa Hospital, Goma, Democratic Republic of Congo
| | | | | | | | - Lisa M Harrison
- Yale Partnerships for Global Health, Yale School of Medicine, New Haven, Connecticut
| | | | - Naomi Abaca Uvon
- Programme National de Lutte contre l'Onchocercose, Ministry of Health, Kinshasa, Democratic Republic of Congo
| | - Sarah K Wendel
- Georgetown University Medical School, Washington, District of Columbia
| | - Clint Trout
- United States Agency for International Development, Yaoundé, Cameroon
| | - Michael Cappello
- Yale Partnerships for Global Health, Yale School of Medicine, New Haven, Connecticut.,Yale School of Public Health, New Haven, Connecticut
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12
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Affiliation(s)
- Peter J Hotez
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and Molecular Virology and Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas; Department of Biology, Baylor University, Waco, Texas; James A Baker III Institute of Public Policy, Rice University, Houston, Texas; Scowcroft Institute of International Affairs, Bush School of Government and Public Policy, Texas A&M University, College Station, Texas
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13
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Chauhan VM, Scurr DJ, Christie T, Telford G, Aylott JW, Pritchard DI. The physicochemical fingerprint of Necator americanus. PLoS Negl Trop Dis 2017; 11:e0005971. [PMID: 29216182 PMCID: PMC5720516 DOI: 10.1371/journal.pntd.0005971] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 09/18/2017] [Indexed: 11/18/2022] Open
Abstract
Necator americanus, a haematophagous hookworm parasite, infects ~10% of the world's population and is considered to be a significant public health risk. Its lifecycle has distinct stages, permitting its successful transit from the skin via the lungs (L3) to the intestinal tract (L4 maturing to adult). It has been hypothesised that the L3 larval sheath, which is shed during percutaneous infection (exsheathment), diverts the immune system to allow successful infection and reinfection in endemic areas. However, the physicochemical properties of the L3 larval cuticle and sheath, which are in direct contact with the skin and its immune defences, are unknown. In the present study, we controlled exsheathment, to characterise the sheath and underlying cuticle surfaces in situ, using atomic force microscopy (AFM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). AFM revealed previously unseen surface area enhancing nano-annuli exclusive to the sheath surface and confirmed greater adhesion forces exist between cationic surfaces and the sheath, when compared to the emergent L3 cuticle. Furthermore, ToF-SIMS elucidated different chemistries between the surfaces of the cuticle and sheath which could be of biological significance. For example, the phosphatidylglycerol rich cuticle surface may support the onward migration of a lubricated infective stage, while the anionic and potentially immunologically active heparan sulphate rich deposited sheath could result in the diversion of immune defences to an inanimate antigenic nidus. We propose that our initial studies into the surface analysis of this hookworm provides a timely insight into the physicochemical properties of a globally important human pathogen at its infective stage and anticipate that the development and application of this analytical methodology will support translation of these findings into a biological context.
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Affiliation(s)
- Veeren M. Chauhan
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham, United Kingdom
- * E-mail: (VMC); (JWA); (DIP)
| | - David J. Scurr
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham, United Kingdom
| | - Thomas Christie
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham, United Kingdom
| | - Gary Telford
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham, United Kingdom
| | - Jonathan W. Aylott
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham, United Kingdom
- * E-mail: (VMC); (JWA); (DIP)
| | - David I. Pritchard
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham, United Kingdom
- * E-mail: (VMC); (JWA); (DIP)
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Pipiková J, Papajová I, Šoltys J, Schusterová I. Occurrence of the most common helminth infections among children in the Eastern Slovak Republic. Public Health 2017. [DOI: 10.1016/j.puhe.2017.05.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Maternal Prenatal Nutrition and Birth Outcomes on Malnutrition among 7- to 10-Year-Old Children: A 10-Year Follow-Up. J Pediatr 2016; 178:40-46.e3. [PMID: 27449363 DOI: 10.1016/j.jpeds.2016.06.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 05/09/2016] [Accepted: 06/06/2016] [Indexed: 11/21/2022]
Abstract
OBJECTIVES To identify postnatal predictors of malnutrition among 7- to 10-year-old children and to assess the long-term effects of antenatal micronutrient supplementation on malnutrition. STUDY DESIGN A follow-up study was conducted to assess the nutritional status of 7- to 10-year-olds (1747 children) whose mothers participated in a cluster-randomized double-blind controlled trial from 2002 to 2006. RESULTS The rate of malnourished 7- to 10-year-olds was 11.1%. A mixed-effects logistic regression model adjusted for the cluster-sampling design indicated that mothers with low prepregnant midupper arm circumference had boys with an increased risk of thinness (aOR 2.05, 95% CI 1.11, 3.79) and girls who were more likely to be underweight (aOR 2.01, 95% CI 1.05, 3.85). Antenatal micronutrient supplementation was not significantly associated with malnutrition. Low birth weight was significantly associated with increased odds of malnutrition among boys (aOR 4.34, 95% CI 1.82, 10.39) and girls (aOR 7.50, 95% CI 3.48, 16.13). Being small for gestational age significantly increased the odds of malnutrition among boys (aOR 1.75, 95% CI 1.01, 3.04) and girls (aOR 4.20, 95% CI 2.39, 7.39). In addition, household wealth, parental height, being picky eater, and illness frequency also predicted malnutrition. CONCLUSIONS Both maternal prenatal nutrition and adverse birth outcomes are strong predictors of malnutrition among early school-aged children. Currently, available evidence is insufficient to support long-term effects of antenatal micronutrient supplementation on children's nutrition. TRIAL REGISTRATION www.isrctn.com: ISRCTN08850194.
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Chesnais CB, Takougang I, Paguélé M, Pion SD, Boussinesq M. Excess mortality associated with loiasis: a retrospective population-based cohort study. THE LANCET. INFECTIOUS DISEASES 2016; 17:108-116. [PMID: 27777031 DOI: 10.1016/s1473-3099(16)30405-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/19/2016] [Accepted: 09/05/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND The burden of loiasis has received limited attention and loiasis is still considered a benign condition. To assess whether loiasis bears any excess mortality, we did a retrospective cohort study in Cameroon. METHODS In 2001, 3627 individuals living in 28 villages were examined for Loa loa infection. In 2016, these villages were revisited and the vital status was determined for 3301 individuals (91%). The data were analysed at community level to assess the relation between the level of L loa infection in 2001 and standardised mortality rates (SMRs), and at individual level to assess the excess mortality relative to the 2001 microfilaraemia and to calculate the population-attributable fraction of mortality associated with L loa microfilaraemia. FINDINGS 915 deaths occurred during the follow-up time (mean time of 12·5 years [IQR 10·2-14·9]) between April, 2001, and March 22, 2016. Crude mortality rate was 20·3 deaths per 1000 person-years. SMRs increased by 4·1% when the proportion of participants infected with greater than 30 000 microfilariae per mL increased by 1% (p=0·030). People aged older than 25 years with greater than 30 000 microfilariae per mL in 2001 died significantly earlier than did amicrofilaraemic people (time ratio 0·67, 95% CI 0·48-0·95, p=0·024). The population-attributable fraction of mortality associated with presence of L loa microfilaraemia was 14·5% (95% CI 6·5-21·8, p=0·001). INTERPRETATION High-grade L loa microfilaraemia is associated with an increased mortality risk, suggesting that loiasis is not a benign condition and merits more attention because of its effect on onchocerciasis and lymphatic control strategies. Loiasis should be considered for inclusion in the WHO's list of neglected tropical diseases. FUNDING Drugs for Neglected Diseases initiative.
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Affiliation(s)
- Cédric B Chesnais
- UMI 233, Institut de Recherche pour le Développement (IRD), Montpellier, France; Montpellier University, Montpellier, France; INSERM Unité 1175, Montpellier, France.
| | - Innocent Takougang
- Faculty of Medicine & Biomedical Sciences-University of Yaounde 1, Yaounde, Cameroon
| | - Marius Paguélé
- Regional Delegation of Public Health, East Region, Cameroon
| | - Sébastien D Pion
- UMI 233, Institut de Recherche pour le Développement (IRD), Montpellier, France; Montpellier University, Montpellier, France; INSERM Unité 1175, Montpellier, France
| | - Michel Boussinesq
- UMI 233, Institut de Recherche pour le Développement (IRD), Montpellier, France; Montpellier University, Montpellier, France; INSERM Unité 1175, Montpellier, France
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Bibi T, Ahmad M, Edwards SE, Tareen NM, Jabeen R, Abdullah I. Ethnomedicinal uses of plants in the treatment of paediatric geohelminth infections in Kalat district of Northern Balochistan, Pakistan. JOURNAL OF ETHNOPHARMACOLOGY 2016; 183:176-186. [PMID: 26927703 DOI: 10.1016/j.jep.2016.02.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 02/20/2016] [Accepted: 02/22/2016] [Indexed: 06/05/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Infection by intestinal parasitic worms (soil-transmitted helminths or geohelminths) is prevalent in many parts of the world, and poses a particular health risk to children. This paper presents findings from a preliminary study with the primary aim to document indigenous knowledge about the use of herbal medicines in the treatment of intestinal worm infections in children among the local communities of Kalat district of northern Balochistan, Pakistan. MATERIALS AND METHODS Ethnomedicinal data were collected through a triangulation approach, that included participant-observation and rapid appraisal methods. Prior-informed consent (PIC) was obtained from participants before conducting structured and semi-structured interviews and delivering an open ended questionnaire. A total of 94 participants, including 28 men (of whom 7 were traditional healers), and 66 women of four different age groups were interviewed. Results were analyzed using quantitative indices of Use Value citations (UVC) and Disease-Consensus Index (DCI). RESULTS Fewer men than women agreed to be interviewed, thus overall women in the area appeared to have more ethnomedicinal knowledge. The majority of study participants belonged to the older age group (>55 years). A total of 49 plant species, belonging to 47 genera, distributed in 30 families were reported. The families Asteraceae and Lamiaceae were most frequently represented, with four species each. Trees were the most common life form, with seeds the most frequently cited plant part used (29%). Nearly a third (31%) of plant-based remedies reported in the treatment of intestinal worms were administered as a decoction. The highest UVC and DCI was reported for the species Ferula assa-foetida sL. (UVC 0.51, DCI 0.46). CONCLUSIONS This study provides previously unreported data on the use of medicinal plants in the treatment of geohelminth infections in children of Kalat. Eight species, Acacia modesta Wall., Asparagus capitatus Baker, Microcephala lamellata (Bunge) Pobed., Nepeta praetervisa Rech.f., Plantago ciliata Desf., Pistacia atlantica Desf., Seriphidium quettense (Podlech) Y.R.Ling and Thymus linearis Benth. are reported here as anthelmintics for the first time. Detailed studies on the anthelmintic activity of chemical constituents of these species are lacking from existing literature. Further phytochemical, pharmacological and toxicity studies are required in order to evaluate the efficacy and safety of these newly reported anthelmintic species. These plants may provide a source of novel anthelmintic drug leads, which are urgently required due to the problem of global anthelmintic resistance.
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Affiliation(s)
- Tahira Bibi
- Department of Plant Sciences, Quaid-i-Azam University, Islamabad, Pakistan; Department of Plant Sciences, Sardar Bahadur Khan Women's University, Quetta, Pakistan.
| | - Mushtaq Ahmad
- Department of Plant Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Sarah E Edwards
- Biodiversity Informatics & Spatial Analysis Department, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK; Centre for Pharmacognosy & Phytotherapy, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AN, UK
| | - Niaz Mohammad Tareen
- Department of Plant Sciences, Sardar Bahadur Khan Women's University, Quetta, Pakistan; Department of Botany, University of Balochistan, Quetta, Pakistan; Bureau of Curriculum and Extension Centre, Quetta, Pakistan
| | - Rukhsana Jabeen
- Department of Plant Sciences, Sardar Bahadur Khan Women's University, Quetta, Pakistan
| | - Irum Abdullah
- Department of Plant Sciences, Quaid-i-Azam University, Islamabad, Pakistan
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Campbell SJ, Nery SV, Doi SA, Gray DJ, Soares Magalhães RJ, McCarthy JS, Traub RJ, Andrews RM, Clements ACA. Complexities and Perplexities: A Critical Appraisal of the Evidence for Soil-Transmitted Helminth Infection-Related Morbidity. PLoS Negl Trop Dis 2016; 10:e0004566. [PMID: 27196100 PMCID: PMC4873196 DOI: 10.1371/journal.pntd.0004566] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Soil-transmitted helminths (STH) have acute and chronic manifestations, and can result in lifetime morbidity. Disease burden is difficult to quantify, yet quantitative evidence is required to justify large-scale deworming programmes. A recent Cochrane systematic review, which influences Global Burden of Disease (GBD) estimates for STH, has again called into question the evidence for deworming benefit on morbidity due to STH. In this narrative review, we investigate in detail what the shortfalls in evidence are. METHODOLOGY/PRINCIPAL FINDINGS We systematically reviewed recent literature that used direct measures to investigate morbidity from STH and we critically appraised systematic reviews, particularly the most recent Cochrane systematic review investigating deworming impact on morbidity. We included six systematic reviews and meta-analyses, 36 literature reviews, 44 experimental or observational studies, and five case series. We highlight where evidence is insufficient and where research needs to be directed to strengthen morbidity evidence, ideally to prove benefits of deworming. CONCLUSIONS/SIGNIFICANCE Overall, the Cochrane systematic review and recent studies indicate major shortfalls in evidence for direct morbidity. However, it is questionable whether the systematic review methodology should be applied to STH due to heterogeneity of the prevalence of different species in each setting. Urgent investment in studies powered to detect direct morbidity effects due to STH is required.
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Affiliation(s)
- Suzy J. Campbell
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| | - Susana V. Nery
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| | - Suhail A. Doi
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
| | - Darren J. Gray
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
- Molecular Parasitology Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Ricardo J. Soares Magalhães
- Children's Health and Environment Program, Queensland Children's Medical Research Institute, The University of Queensland, Brisbane, Queensland, Australia
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia
| | - James S. McCarthy
- School of Population Health, University of Queensland, Brisbane, Queensland, Australia
- Clinical Tropical Medicine Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Rebecca J. Traub
- Faculty of Veterinary and Agricultural Science, The University of Melbourne, Melbourne, Victoria, Australia
| | - Ross M. Andrews
- Menzies School of Health Research, Charles Darwin University, Darwin, Northern Territory, Australia
| | - Archie C. A. Clements
- Research School of Population Health, College of Medicine, Biology, and Environment, The Australian National University, Canberra, Australian Captial Territory, Australia
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Mama M, Alemu G. Prevalence and factors associated with intestinal parasitic infections among food handlers of Southern Ethiopia: cross sectional study. BMC Public Health 2016; 16:105. [PMID: 26831331 PMCID: PMC4736149 DOI: 10.1186/s12889-016-2790-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 01/27/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Globally about one third of the total population is estimated to be infected with intestinal parasites, of which, the majority are people living in tropical and sub-tropical parts of the world. Cases of intestinal parasitosis are also highly abundant in Ethiopia and hence the aim of present study was to assess prevalence and predictors of intestinal parasitic infections among food handlers working in Arba Minch University students' cafeteria, South Ethiopia. METHOD A cross sectional study was conducted among food handlers working in Arba Minch University from April to June, 2015. A pretested structured questionnaire was used for collecting data about socio-demographic characteristics and possible risk factors. Stool specimens were collected and examined microscopically for the presence of eggs, cysts and trophozoites of intestinal parasites. Data entry and analysis were done using SPSS version 20 software. RESULTS A total of 376 food handlers were enrolled in the study of which thirty one of them were not willing to participate for a stool examination. The majority of study participants were females 273 (72.6 %). About 123 (36 %) of food handlers were found to be positive for different intestinal parasites with the most abundant parasite of Entamoeba histolytica/dispar 48 (14 %) followed by Ascaris lumbricoides 32 (9.27 %). Finger nail status (AOR: 2.2, 95 % CI: 1.29-3.72), hand washing practice after toilet (AOR: 1.71, 95 % CI: 1.06-2.77), hand washing practice before food handling (AOR: 1.69, 95 % CI: 1.04-2.75), preparing food when suffering from diseases (AOR: 3.08, 95 % CI: 1.17-8.13), and using common knife for cutting raw flesh food and other food (AOR: 1.72, 95 % CI: 1.01-2.92) were independent predictors of intestinal parasitic infection among the food handlers. CONCLUSION This study revealed a high prevalence of intestinal parasites among food handlers. Since most of the intestinal parasites are transmitted by the feco-oral route, food handlers could be an important source of infection to the students and general population. Therefore, constant epidemiological surveillance through biannual routine parasitological tests and treatment of the infected cases along with the improvement of personal hygiene and environmental sanitation are recommended to control the parasitic infection in food handlers.
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Affiliation(s)
- Mohammedaman Mama
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia.
| | - Getaneh Alemu
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia.
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Terefe B, Zemene E, Mohammed AE. Intestinal helminth infections among inmates in Bedele prison with emphasis on soil-transmitted helminths. BMC Res Notes 2015; 8:779. [PMID: 26666341 PMCID: PMC4677449 DOI: 10.1186/s13104-015-1775-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 11/30/2015] [Indexed: 11/18/2022] Open
Abstract
Background Intestinal helminths infect more than two billion people worldwide. They are common in developing countries where sanitary facilities are inadequate. There is scarcity of documented data on the magnitude of intestinal helminths among inmates in Ethiopia. The aim of this study was to determine prevalence of intestinal helminth infections among inmates in Bedele prison, south-western Ethiopia. Methods A cross-sectional study involving 234 inmates in Bedele prison was conducted in April 2012. Socio-demographic data was collected from each study participant using semi-structured questionnaire. Fresh stool specimens were collected and processed using modified McMaster technique. Results At least one species of intestinal helminth was identified in 111 (47.4 %) of the inmates. Ascaris lumbricoides was the most predominant parasite isolated, followed by the hookworms. Most of the cases of soil-transmitted helminths (STHs) were light infections. Untrimmed hand fingernails was significantly associated with A. lumbricoides infection (AOR 0.383, 95 % CI 0.200–0.731). Conclusion Intestinal helminths are common among the inmates in Bedele prison. Health information should be given to the inmates on proper personal hygiene practices with emphasis on trimming of hand fingernails. Monitoring helminth infections in the inmate population is required.
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Affiliation(s)
- Bahiru Terefe
- Jimma University Specialized Hospital Laboratory, Jimma University, Jimma, Ethiopia.
| | - Endalew Zemene
- Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia.
| | - Abdurehman E Mohammed
- Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia.
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Shiferaw MB, Mengistu AD. Helminthiasis: Hookworm Infection Remains a Public Health Problem in Dera District, South Gondar, Ethiopia. PLoS One 2015; 10:e0144588. [PMID: 26657490 PMCID: PMC4684337 DOI: 10.1371/journal.pone.0144588] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 11/20/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Intestinal parasitic infections are significant cause of morbidity and mortality in endemic countries. In Ethiopia, helminthiasis was the third leading cause of outpatient visits. Despite the health extension program was launched to address this problem, there is limited information on the burden of intestinal parasites after implementation of the program in our setting. Therefore, the aim of this study was to assess the intestinal helminthic infections among clients attending at Anbesame health center, South Gondar, Ethiopia. METHODS A cross sectional study was conducted at Anbesame health center from March to June 2015. A structured questionnaire was used to collect data from 464 study participants selected consecutively. Stool specimen collection, processing through formol-ether concentration technique and microscopic examination for presence of parasites were carried out. Data were entered, cleaned and analyzed using SPSS Version 20. RESULTS Among the total 464 study participants with median (±IQR) age of 25.0 (±21.75) years, 262 (56.5%) were females. Helminthic infection was found in 97 (20.9%) participants. Hookworm (68 [14.7%]) was the predominant parasite followed by S. mansoni (11 [2.4%]), E. vermicularis (9 [1.9%]) and S. stercoralis (5 [1.1%]). Patients with age group ≥15 years (AOR: 5.26; 95% CI: 2.05-13.46; P: 0.001) and walking barefoot (AOR: 2.20; 95% CI: 1.08-4.48; P: 0.031) were more vulnerable from the hookworm infections. CONCLUSIONS There was a high burden of hookworm infections in our setting. Hence, regular shoes wearing, considering all age groups in the albendazole deworming as mass treatment and environmental hygiene are important interventions to reduce the burden of such neglected tropical disease.
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Turner HC, Truscott JE, Bettis AA, Shuford KV, Dunn JC, Hollingsworth TD, Brooker SJ, Anderson RM. An economic evaluation of expanding hookworm control strategies to target the whole community. Parasit Vectors 2015; 8:570. [PMID: 26542226 PMCID: PMC4635541 DOI: 10.1186/s13071-015-1187-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 10/23/2015] [Indexed: 11/10/2022] Open
Abstract
Background The WHO treatment guidelines for the soil-transmitted helminths (STH) focus on targeting children for the control of morbidity induced by heavy infections. However, unlike the other STHs, the majority of hookworm infections are harboured by adults. This untreated burden may have important implications for controlling both hookworm’s morbidity and transmission. This is particularly significant in the context of the increased interest in investigating STH elimination strategies. Methods We used a deterministic STH transmission model and parameter estimates derived from field epidemiological studies to evaluate the impact of child-targeted (2–14 year olds) versus community-wide treatment against hookworm in terms of preventing morbidity and the timeframe for breaking transmission. Furthermore, we investigated how mass treatment may influence the long-term programmatic costs of preventive chemotherapy for hookworm. Results The model projected that a large proportion of the overall morbidity due to hookworm was unaffected by the current child-targeted strategy. Furthermore, driving worm burdens to levels low enough to potentially break transmission was only possible when using community-wide treatment. Due to these projected reductions in programme duration, it was possible for community-wide treatment to generate cost savings – even if it notably increases the annual distribution costs. Conclusions Community-wide treatment is notably more cost-effective for controlling hookworm’s morbidity and transmission than the current child-targeted strategies and could even be cost-saving in many settings in the longer term. These calculations suggest that it is not optimum to treat using the same treatment strategies as other STH. Hookworm morbidity and transmission control require community-wide treatment. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1187-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hugo C Turner
- London Centre for Neglected Tropical Disease Research, London, UK. .,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - James E Truscott
- London Centre for Neglected Tropical Disease Research, London, UK. .,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - Alison A Bettis
- London Centre for Neglected Tropical Disease Research, London, UK. .,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - Kathryn V Shuford
- London Centre for Neglected Tropical Disease Research, London, UK. .,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - Julia C Dunn
- London Centre for Neglected Tropical Disease Research, London, UK. .,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
| | - T Déirdre Hollingsworth
- Mathematics Institute, University of Warwick, Coventry, CV4 7AL, UK. .,School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
| | - Simon J Brooker
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
| | - Roy M Anderson
- London Centre for Neglected Tropical Disease Research, London, UK. .,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Marys Campus, Imperial College London, Norfolk Place, London, W2 1PG, UK.
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Siza JE, Kaatano GM, Chai JY, Eom KS, Rim HJ, Yong TS, Min DY, Chang SY, Ko Y, Changalucha JM. Prevalence of Schistosomes and Soil-Transmitted Helminths and Morbidity Associated with Schistosomiasis among Adult Population in Lake Victoria Basin, Tanzania. THE KOREAN JOURNAL OF PARASITOLOGY 2015; 53:525-33. [PMID: 26537031 PMCID: PMC4635833 DOI: 10.3347/kjp.2015.53.5.525] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/30/2015] [Accepted: 10/04/2015] [Indexed: 11/23/2022]
Abstract
The objective of this study was to carry out a community survey on schistosomiais and soil-transmitted helminth (STH) infections in order to suggest feasible and effective intervention strategies in Lake Victoria basin, Tanzania. A total of 37 communities selected from 23 districts of the 4 regions in the Lake Victoria basin of Tanzania were involved in the study. From each of the selected locality, 50 adult community members, 25 males and 25 females, were recruited for the study. Each study participant was requested to submit stool and urine specimens. From each stool specimen, duplicate Kato-Katz thick smears were prepared and microscopically examined for Schistosoma mansoni and STH eggs. Urine specimens were processed by the filtration technique and microscopically examined for Schistosoma haematobium eggs. Ultrasound examination for morbidity due to schistosomiasis was performed. Mass treatment was done using praziquantel and albendazole for schistosome and STHs infections, respectively. Out of 1,606 adults who provided stool specimens, 199 (12.4%) were positive for S. mansoni, 349 (21.7%) for hookworms, 133 (8.3%) for Ascaris lumbricoides, and 33 (2.0%) for Trichuris trichiura. Out of 1,400 participants who provided urine specimens, 25 (1.8%) were positive for S. haematobium eggs. Because of the co-endemicity of these afflictions and their impact on vulnerable population groups, the helminthiasis could be simultaneously treated with 2 drugs, praziquantel for schistosomiasis and albendazole for STHs.
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Affiliation(s)
- Julius E Siza
- National Institute of Medical Research, P.O. Box 1462, Mwanza, Tanzania
| | - Godfrey M Kaatano
- National Institute of Medical Research, P.O. Box 1462, Mwanza, Tanzania
| | - Jong-Yil Chai
- Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Keeseon S Eom
- Department of Parasitology and Medical Research Institute, Chungbuk National University School of Medicine, Cheongju 28644, Korea
| | - Han-Jong Rim
- Department of Parasitology, College of Medicine, Korea University, Seoul 02841, Korea
| | - Tai-Soon Yong
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Duk-Young Min
- Department of Microbiology and Immunology, Eulji University College of Medicine, Daejeon 35233, Korea
| | - Su Young Chang
- Good Neighbors International, Tanzania Western Chapter, P.O. Box 367, Mwanza, Tanzania
| | - Yunsuk Ko
- Good Neighbors International, Tanzania Western Chapter, P.O. Box 367, Mwanza, Tanzania
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Tefera E, Mohammed J, Mitiku H. Intestinal helminthic infections among elementary students of Babile town, eastern Ethiopia. Pan Afr Med J 2015; 20:50. [PMID: 26090008 PMCID: PMC4449975 DOI: 10.11604/pamj.2015.20.50.5251] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 10/31/2014] [Indexed: 11/11/2022] Open
Abstract
INTRODUCTION Intestinal helminthic infections are important public health problems in developing countries. In Ethiopia, intestinal parasitic infections are highly prevalent because of low living standards and poor environmental sanitation. There are several areas in Ethiopia from which epidemiological information is lacking including Babile town. The aim of this study was to determine the prevalence of intestinal helminthic infection among students of Babile town. METHODS A cross sectional study was conducted from May 14 to June 08, 2012. Stool samples collected from 644 students were examined by the McMaster method. Data were analyzed using SPSS version 16.0. Univariate analysis was carried out using the Chi-square test to check for presence or absence of association between exposure and the presence of infection and odds ratios with 95% CI were computed to measure the strength of association. Logistic regression was used to calculate predictors of helminthic infection. Statistical significance was set at P<0.05. RESULTS The prevalence of intestinal helminths was 13.8%, of which three students were infected with soil transmitted helminths with a prevalence rate of 0.47%. The prevalence of Hymenolepis nana, Enterobius vermicularis, hookworm, and Trichiura trichiura infections were 13, 0.6, 0.3, and 0.2% respectively. Intestinal helminthic infection was significantly associated with grade and sex of the school children. CONCLUSION The prevalence of intestinal helminths was low. Health information dissemination is recommended. Since infection by Hymenolepis nana is a long term health problem in the area, provision of regular treatment by anthelminthic drug of choice for hymenolepiasis is also recommended.
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Affiliation(s)
- Ephrem Tefera
- Department of Medical Laboratory Sciences, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Jemal Mohammed
- Department of Medical Laboratory Sciences, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
| | - Habtamu Mitiku
- Department of Medical Laboratory Sciences, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia
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King CH. Health metrics for helminth infections. Acta Trop 2015; 141:150-60. [PMID: 24333545 DOI: 10.1016/j.actatropica.2013.12.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 11/30/2013] [Accepted: 12/03/2013] [Indexed: 01/13/2023]
Abstract
Health metrics based on health-adjusted life years have become standard units for comparing the disease burden and treatment benefits of individual health conditions. The Disability-Adjusted Life Year (DALY) and the Quality-Adjusted Life Year (QALY) are the most frequently used in cost-effect analyses in national and global health policy discussions for allocation of health care resources. While sometimes useful, both the DALY and QALY metrics have limitations in their ability to capture the full health impact of helminth infections and other 'neglected tropical diseases' (NTDs). Gaps in current knowledge of disease burden are identified, and interim approaches to disease burden assessment are discussed.
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Andereck JW, Kipp AM, Ondiek M, Vermund SH. Helminth prevalence among adults in rural Kenya: a stool survey for soil-transmitted helminths and schistosomiasis in Nyanza province. Trans R Soc Trop Med Hyg 2014; 108:804-9. [PMID: 25359321 DOI: 10.1093/trstmh/tru164] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Soil-transmitted helminth (STH) prevalence in children is high in rural southwestern Kenya, but adult prevalence data are scarce. A 2010 study of a village in Nyanza province found a pediatric STH prevalence of 44% using a direct stool-smear method. Adult STH prevalence and associated predictors was measured in the same village. METHODS Adults (≥18 years) presenting at the out-patient department of the small hospital or community outreach events completed a short questionnaire and provided stool samples. Light microscopy for ova and larvae was conducted using a stool concentration technique to improve sensitivity. Multivariable regression models were used to identify predictors of STH prevalence. RESULTS Among 344 adults, STH prevalence was 15.7% (54/344). Hookworm was most common (13.1%; 45/344), followed by Ascaris lumbricoides (6.1%; 21/344) and Trichuris trichiura (0.6%; 2/344). Twelve participants (3.5%; 12/344) had multiple STHs and three (0.9%; 3/344) had Schistosoma mansoni. Female sex, older age and lower education level were significant STH predictors. CONCLUSIONS Adult STH prevalence was lower than previous studies of children from the same village. Adults with the identified risk factors had a prevalence of ≥20%, which may warrant periodic, targeted deworming of adults with these risk factors given the low cost and low toxicity of anthelmintic drugs.
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Affiliation(s)
| | - Aaron M Kipp
- Vanderbilt Institute for Global Health, Nashville, Tennessee, USA Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | | | - Sten H Vermund
- Vanderbilt Institute for Global Health, Nashville, Tennessee, USA Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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Wiśniewski M, Lapiński M, Zdziarska A, Długosz E, Bąska P. Molecular cloning and analysis of Ancylostoma ceylanicum glutamate-cysteine ligase. Mol Biochem Parasitol 2014; 196:12-20. [PMID: 25092620 DOI: 10.1016/j.molbiopara.2014.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 06/13/2014] [Accepted: 07/08/2014] [Indexed: 01/25/2023]
Abstract
Glutamate-cysteine ligase (GCL) is a heterodimer enzyme composed of a catalytic subunit (GCLC) and a modifier subunit (GCLM). This enzyme catalyses the synthesis of γ-glutamylcysteine, a precursor of glutathione. cDNAs of the putative glutamate-cysteine ligase catalytic (Ace-GCLC) and modifier subunits (Ace-GCLM) of Ancylostoma ceylanicum were cloned using the RACE-PCR amplification method. The Ace-gclc and Ace-gclm cDNAs encode proteins with 655 and 254 amino acids and calculated molecular masses of 74.76 and 28.51kDa, respectively. The Ace-GCLC amino acid sequence shares about 70% identity and 80% sequence similarity with orthologs in Loa loa, Onchocerca volvulus, Brugia malayi, and Ascaris suum, whereas the Ace-GCLM amino acid sequence has only about 30% sequence identity and 50% similarity to homologous proteins in those species. Real-time PCR analysis of mRNA expression in L3, serum stimulated L3 and adult stages of A. ceylanicum showed the highest level of Ace-GCLC and Ace-GCLM expression occurred in adult worms. No differences were detected among adult hookworms harvested 21 and 35dpi indicating expression of Ace-gclc and Ace-gclm in adult worms is constant during the course of infection. Positive interaction between two subunits of glutamate-cysteine ligase was detected using the yeast two-hybrid system, and by specific enzymatic reaction. Ace-GCL is an intracellular enzyme and is not exposed to the host immune system. Thus, as expected, we did not detect IgG antibodies against Ace-GCLC or Ace-GCLM on days 21, 60 and 120 of A. ceylanicum infection in hamsters. Furthermore, vaccination with one or both antigens did not reduce worm burdens, and resulted in no improvement of clinical parameters (hematocrit and hemoglobin) of infected hamsters. Therefore, due to the significant role of the enzyme in parasite metabolism, our analyses raises hope for the development of a successful new drug against ancylostomiasis based on the specific GCL inhibitor.
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Affiliation(s)
- Marcin Wiśniewski
- Division of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Ciszewskiego 8, 02-786 Warsaw, Poland.
| | - Maciej Lapiński
- Division of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Ciszewskiego 8, 02-786 Warsaw, Poland
| | - Anna Zdziarska
- Division of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Ciszewskiego 8, 02-786 Warsaw, Poland
| | - Ewa Długosz
- Division of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Ciszewskiego 8, 02-786 Warsaw, Poland
| | - Piotr Bąska
- Division of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Ciszewskiego 8, 02-786 Warsaw, Poland
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Bisanzio D, Mutuku F, Bustinduy AL, Mungai PL, Muchiri EM, King CH, Kitron U. Cross-sectional study of the burden of vector-borne and soil-transmitted polyparasitism in rural communities of Coast Province, Kenya. PLoS Negl Trop Dis 2014; 8:e2992. [PMID: 25057825 PMCID: PMC4109907 DOI: 10.1371/journal.pntd.0002992] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 05/20/2014] [Indexed: 11/18/2022] Open
Abstract
Background In coastal Kenya, infection of human populations by a variety of parasites often results in co-infection or poly-parasitism. These parasitic infections, separately and in conjunction, are a major cause of chronic clinical and sub-clinical human disease and exert a long-term toll on economic welfare of affected populations. Risk factors for these infections are often shared and overlap in space, resulting in interrelated patterns of transmission that need to be considered at different spatial scales. Integration of novel quantitative tools and qualitative approaches is needed to analyze transmission dynamics and design effective interventions. Methodology Our study was focused on detecting spatial and demographic patterns of single- and co-infection in six villages in coastal Kenya. Individual and household level data were acquired using cross-sectional, socio-economic, and entomological surveys. Generalized additive models (GAMs and GAMMs) were applied to determine risk factors for infection and co-infections. Spatial analysis techniques were used to detect local clusters of single and multiple infections. Principal findings Of the 5,713 tested individuals, more than 50% were infected with at least one parasite and nearly 20% showed co-infections. Infections with Schistosoma haematobium (26.0%) and hookworm (21.4%) were most common, as was co-infection by both (6.3%). Single and co-infections shared similar environmental and socio-demographic risk factors. The prevalence of single and multiple infections was heterogeneous among and within communities. Clusters of single and co-infections were detected in each village, often spatially overlapped, and were associated with lower SES and household crowding. Conclusion Parasitic infections and co-infections are widespread in coastal Kenya, and their distributions are heterogeneous across landscapes, but inter-related. We highlighted how shared risk factors are associated with high prevalence of single infections and can result in spatial clustering of co-infections. Spatial heterogeneity and synergistic risk factors for polyparasitism need to be considered when designing surveillance and intervention strategies. In Coast Province, Kenya, infections with Schistosoma haematobium, Plasmodium spp., filarial nematodes, and geohelminths are common, resulting in high levels of both single infections and polyparasitism. The long-term effect of these infections, separately or in combination, has a major impact on human health and on the economic welfare of affected populations. The transmission dynamics of these parasitic infections can be linked to shared risk factors that often overlap in space. We studied human and environmental factors driving transmission and the resulting spatial pattern of infections in six communities, using cross-sectional, socio-economic and entomological surveys. Single and co-infections were widespread in the communities, and were associated with environmental, demographic and socio-economic risk factors, including distance of community from the coast, sanitation and human age and crowding. The spatial patterns of single and co-infections were heterogeneous among and within communities, with overlapping clusters of single and multiple infections in areas where houses with lower socio-economic status and more crowding were located. The heterogeneities among and within communities can provide important insights when designing surveillance and intervention strategies when planning appropriate surveillance and control strategies targeting polyparasitism.
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Affiliation(s)
- Donal Bisanzio
- Department of Environmental Sciences, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
| | - Francis Mutuku
- Department of Environmental Sciences, Emory University, Atlanta, Georgia, United States of America
- Department of Environment and Health Sciences, Technical University of Mombasa, Mombasa, Kenya
| | - Amaya L. Bustinduy
- Parasitology Department, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Peter L. Mungai
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Eric M. Muchiri
- Division of Vector-Borne and Neglected Tropical Diseases, Ministry of Public Health and Sanitation, Nairobi, Kenya
| | - Charles H. King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Uriel Kitron
- Department of Environmental Sciences, Emory University, Atlanta, Georgia, United States of America
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Identification and preservation of intestinal parasites using methylene blue-glycerol mount: a new approach to stool microscopy. J Parasitol Res 2014; 2014:672018. [PMID: 24818011 PMCID: PMC4003778 DOI: 10.1155/2014/672018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 03/19/2014] [Accepted: 03/27/2014] [Indexed: 11/17/2022] Open
Abstract
We have tried a new approach to routine stool microscopy by using a combination of methylene blue and glycerol in wet mount preparation of fresh faecal samples for the demonstration of medically important intestinal parasites. This combination was evaluated for finding differences in the details and clarity of morphology and internal structures of parasites under low- and high-power microscopy as compared to iodine and saline mount. It was further evaluated to estimate the time taken by methylene blue-glycerol mount to dry up as compared to iodine and saline wet mount.
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Comparative study of the prevalence of intestinal parasites in low socioeconomic areas from South chennai, India. J Parasitol Res 2014; 2014:630968. [PMID: 24587897 PMCID: PMC3918716 DOI: 10.1155/2014/630968] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Accepted: 11/29/2013] [Indexed: 12/19/2022] Open
Abstract
Intestinal parasites cause one of the most important health problems through their effects in causing undernourishment morbidity and incapacitation due to their behavior particularly in children compared to adults. This study was intended to state the prevalence of intestinal parasites between the slum dwellers of different areas in south Chennai. Among the total of 256 samples collected between the ages of 0-50 yrs, 194 samples were positive. Standard laboratory techniques for parasitological diagnosis were carried out for each sample. Entamoeba coli (23%), Cyclospora sp. (22.2%), Entamoeba histolytica (21.8%), Giardia intestinalis (14.4%), Ascaris lumbricoides (6.2%), Trichuris trichiura (1.1%), and Hymenolepis nana (2.7%) were found in the dwellers of low socioeconomic areas. The data on the prevalence of parasites with respect to sex and age showed that the females harbored more numbers of parasites when compared to males. Further, with respect to age, children and teenagers had surplus parasites compared to old age groups. The percentage of educational status showed a reduction in the number of parasites in the higher education dwellers. These parasites could be prevented by possible grouping of better ecological design and hygiene. Conclusively, the examination of personal hygiene as well as routine medical examination and treatment is strongly recommended in the low socio-economic areas.
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Pullan RL, Smith JL, Jasrasaria R, Brooker SJ. Global numbers of infection and disease burden of soil transmitted helminth infections in 2010. Parasit Vectors 2014; 7:37. [PMID: 24447578 PMCID: PMC3905661 DOI: 10.1186/1756-3305-7-37] [Citation(s) in RCA: 863] [Impact Index Per Article: 86.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 01/06/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Quantifying the burden of parasitic diseases in relation to other diseases and injuries requires reliable estimates of prevalence for each disease and an analytic framework within which to estimate attributable morbidity and mortality. Here we use data included in the Global Atlas of Helminth Infection to derive new global estimates of numbers infected with intestinal nematodes (soil-transmitted helminths, STH: Ascaris lumbricoides, Trichuris trichiura and the hookworms) and use disability-adjusted life years (DALYs) to estimate disease burden. METHODS Prevalence data for 6,091 locations in 118 countries were sourced and used to estimate age-stratified mean prevalence for sub-national administrative units via a combination of model-based geostatistics (for sub-Saharan Africa) and empirical approaches (for all other regions). Geographical variation in infection prevalence within these units was approximated using modelled logit-normal distributions, and numbers of individuals with infection intensities above given thresholds estimated for each species using negative binomial distributions and age-specific worm/egg burden thresholds. Finally, age-stratified prevalence estimates for each level of infection intensity were incorporated into the Global Burden of Disease Study 2010 analytic framework to estimate the global burden of morbidity and mortality associated with each STH infection. RESULTS Globally, an estimated 438.9 million people (95% Credible Interval (CI), 406.3 - 480.2 million) were infected with hookworm in 2010, 819.0 million (95% CI, 771.7 - 891.6 million) with A. lumbricoides and 464.6 million (95% CI, 429.6 - 508.0 million) with T. trichiura. Of the 4.98 million years lived with disability (YLDs) attributable to STH, 65% were attributable to hookworm, 22% to A. lumbricoides and the remaining 13% to T. trichiura. The vast majority of STH infections (67%) and YLDs (68%) occurred in Asia. When considering YLDs relative to total populations at risk however, the burden distribution varied more considerably within major global regions than between them. CONCLUSION Improvements in the cartography of helminth infection, combined with mathematical modelling approaches, have resulted in the most comprehensive contemporary estimates for the public health burden of STH. These numbers form an important benchmark upon which to evaluate future scale-up of major control efforts.
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Affiliation(s)
- Rachel L Pullan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Jennifer L Smith
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Rashmi Jasrasaria
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, USA
- Stanford University School of Medicine, Stanford, CA, USA
| | - Simon J Brooker
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
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Sesay S, Paye J, Bah MS, McCarthy FM, Conteh A, Sonnie M, Hodges MH, Zhang Y. Schistosoma mansoni infection after three years of mass drug administration in Sierra Leone. Parasit Vectors 2014; 7:14. [PMID: 24401567 PMCID: PMC3895768 DOI: 10.1186/1756-3305-7-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 01/06/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Schistosoma mansoni was moderately-highly endemic in the northeast of Sierra Leone. The national neglected tropical disease control program started mass drug administration (MDA) with praziquantel (PZQ) in six districts in 2009 targeting primary school children only. The effort was scaled-up to seven districts in 2010 targeting school aged children (SAC) and at-risk adults. A cross-sectional sentinel site survey was conducted in 2012 after three rounds of MDA to evaluate the impact of the national program. METHODS Twenty-six (26) sentinel sites were randomly selected from the baseline mapping survey sites stratified according to the baseline prevalence into high, moderate or low endemic category. Fifty (50) school children (25 males and 25 females) were randomly selected per site. Fresh stool samples were examined in the field using the Kato Katz technique. The results were compared with the baseline data. RESULTS Program coverage of 94.8%, 77.1% and 81.7% was reported in 2009, 2010 and 2011 respectively. Independent monitoring in 2011 showed program coverage of 83.9%, not significantly different from the reported result in the same year. The overall prevalence of S. mansoni was 16.3% (95% CI: 14.4-18.4%) and mean intensity was 18.98 epg (95% CI: 11.46-26.50 epg) in 2012, representing 67.2% and 85.9% reduction from the baseline respectively. The proportion of moderately and heavily infected children was 3.3% and 1.2%, a significant reduction from 18.2% and 8.8% at baseline respectively. CONCLUSIONS Sierra Leone has maintained effective MDA coverage with PZQ since 2009. Three rounds of MDA led to a significant reduction of S. mansoni infection in the country. In line with the significant progress made in controlling schistosomiasis, the national treatment strategy has been reviewed and MDA will be expanded to include school age children in low endemicity districts with the new national objective for the elimination of schistosomiasis. Sierra Leone is well on its way to eliminate schistosomiasis as a public health problem.
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Affiliation(s)
| | | | | | | | | | | | - Mary H Hodges
- Helen Keller International, PO Box 352, Freetown, Sierra Leone.
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Singer M, Bulled N. INTERLOCKED INFECTIONS: THE HEALTH BURDENS OF SYNDEMICS OF NEGLECTED TROPICAL DISEASES. ANNALS OF ANTHROPOLOGICAL PRACTICE 2013. [DOI: 10.1111/napa.12007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Nasr NA, Al-Mekhlafi HM, Ahmed A, Roslan MA, Bulgiba A. Towards an effective control programme of soil-transmitted helminth infections among Orang Asli in rural Malaysia. Part 1: prevalence and associated key factors. Parasit Vectors 2013; 6:27. [PMID: 23356952 PMCID: PMC3564908 DOI: 10.1186/1756-3305-6-27] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 01/24/2013] [Indexed: 11/10/2022] Open
Abstract
Background Despite the continuous efforts to improve the quality of life of Orang Asli (Aborigines) communities, these communities are still plagued with a wide range of health problems including parasitic infections. The first part of this study aimed at determining the prevalence of soil-transmitted helminth (STH) infections and identifying their associated factors among rural Orang Asli children. Methods A cross-sectional study was carried out among 484 Orang Asli children aged ≤ 15 years (235 females and 249 males) belonging to 215 households from 13 villages in Lipis district, Pahang, Malaysia. Faecal samples were collected and examined by using formalin-ether sedimentation, Kato Katz and Harada Mori techniques. Demographic, socioeconomic, environmental and behavioural information were collected by using a pre-tested questionnaire. Results Overall, 78.1% of the children were found to be infected with one or more STH species. The prevalence of trichuriasis, ascariasis and hookworm infections were 71.7%, 37.4% and 17.6%, respectively. Almost all, three quarters and one fifth of trichuriasis, ascariasis and hookworm infections, respectively, were of moderate-to-heavy intensities. Multiple logistic regression analysis showed that age of ≥ 6 years (school-age), using unsafe water supply as a source for drinking water, absence of a toilet in the house, large family size (≥ 7 members), not washing hands before eating, and not washing hands after defecation were the key factors significantly associated with STH among these children. Conclusion This study reveals an alarmingly high prevalence of STH among Orang Asli children and clearly brings out an urgent need to implement school-based de-worming programmes and other control measures like providing a proper sanitation, as well as a treated drinking water supply and proper health education regarding good personal hygiene practices. Such an integrated control program will help significantly in reducing the prevalence and intensity of STH in Orang Asli communities.
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Affiliation(s)
- Nabil A Nasr
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Nasr NA, Al-Mekhlafi HM, Ahmed A, Roslan MA, Bulgiba A. Towards an effective control programme of soil-transmitted helminth infections among Orang Asli in rural Malaysia. Part 2: Knowledge, attitude, and practices. Parasit Vectors 2013; 6:28. [PMID: 23356968 PMCID: PMC3571980 DOI: 10.1186/1756-3305-6-28] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 01/24/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In the first part of this study, we investigated the prevalence and associated key factors of soil-transmitted helminth (STH) infections among Orang Asli children in rural Malaysia; an alarming high prevalence and five key factors significantly associated with infections were reported. Part 2 of this study aims to evaluate the knowledge, attitude and practices (KAP) on STH infections among Orang Asli in Peninsular Malaysia. METHODS A cross-sectional study was carried out among 215 households from 13 villages in Lipis district, Pahang, Malaysia. Demographic and socioeconomic information of the participants and their KAP on STH were collected by using a pre-tested questionnaire. RESULTS Overall, 61.4% of the participants had prior knowledge about intestinal helminths with a lack of knowledge on the transmission (28.8%), signs and symptoms (29.3%) as well as the prevention (16.3%). Half of the respondents considered STH as harmful, while their practices to prevent infections were still inadequate. Significant associations between the KAP and age, gender, educational and employment status, family size, and household monthly income were reported. Moreover, significantly lower prevalence of STH infections was reported among children of respondents who wear shoes/slippers when outside the house (72.8%; 95% CI= 62.6, 80.5 vs 87.0%; 95% CI= 81.4, 91.1), wash their hands before eating (32.4%; 95% CI= 24.3, 42.2 vs 51.4%; 95% CI= 44.7, 60.1), and wash their hands after defecation (47.8%; 95% CI= 35.7, 57.1 vs 69.2%; 95% CI= 63.7, 78.7) as compared to their counterparts. Multiple logistic regression analysis indicated that the educational level of the respondents was the most important factor significantly associated with the KAP on STH among this population. CONCLUSION This study reveals inadequate knowledge, attitude and practices on STH infections among Orang Asli in rural Malaysia. Hence, there is a great need for a proper health education programme and community mobilisation to enhance prevention and instil better knowledge on STH transmission and prevention. This is crucial for an effective and sustainable STH control programme to save the lives and future of the most vulnerable children in rural Malaysia.
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Affiliation(s)
- Nabil A Nasr
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, 50603, Malaysia
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Tanner S, Rosinger A, Leonard WR, Reyes-García V. Health and adult productivity: the relation between adult nutrition, helminths, and agricultural, hunting, and fishing yields in the Bolivian Amazon. Am J Hum Biol 2012. [PMID: 23180686 DOI: 10.1002/ajhb.22350] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVES Infectious disease and nutritional stress have both been associated with reductions in adult work productivity and work capacity in the context of wage labor, but less research has investigated their effects among groups relying on more traditional subsistence practices of horticulture and foraging. In this article, we examine the relations among measures of adult nutritional status (BMI, skinfold measurements, and fat-free mass) and infection (presence of soil transmitted helminth infections) and measures of adult work productivity. METHODS As part of a larger panel study among Tsimane', a foraging-horticulturalist group in the Bolivian Amazon, health surveys, anthropometric information, and the quantity of products (both crops and game) brought into the household were collected for 320 Tsimane' adults over a four-month period in 2003. In addition, a single fecal sample was collected for a sub-sample of 86 adults. RESULTS Our analysis shows mixed associations between either BMI or the presence of parasitism and reported adult productivity. Muscularity was not clearly related to adult productivity. In contrast, body fatness (Skinfold z-score) was inversely associated with the average quantity of fish and game brought into the household, especially for men. CONCLUSIONS These findings suggest that the effects of adult infection and nutritional stress may be less clearly identified outside of the context of wage labor. Further research linking adult physical activity levels and metabolic rates to productivity in diverse contexts is needed.
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Affiliation(s)
- S Tanner
- Department of Anthropology, University of Georgia, Athens, Georgia 30602, USA.
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Hodges MH, Dada N, Warmsley A, Paye J, Bangura MM, Nyorkor E, Sonnie M, Zhang Y. Mass drug administration significantly reduces infection of Schistosoma mansoni and hookworm in school children in the national control program in Sierra Leone. BMC Infect Dis 2012; 12:16. [PMID: 22264258 PMCID: PMC3282666 DOI: 10.1186/1471-2334-12-16] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 01/22/2012] [Indexed: 11/17/2022] Open
Abstract
Background The first-ever round of school-based mass drug administration (MDA) with praziquantel together with mebendazole targeting school-aged children in endemic districts was conducted in 2009 by the National Neglected Tropical Diseases Control Program. To evaluate the impact of the treatment regimen, a cross-sectional sentinel site survey was conducted 6 months post-MDA. Methods Fifteen sentinel schools from six highly endemic districts (according to data from national and pre-MDA surveys) with Schistosoma mansoni affecting over 50% of the population, and moderate to high prevalence of hookworms (> 20%). Approximately 30 children aged 9-14 years were selected from each school and stool samples (one per student) were examined by the Kato-Katz method. Results The overall prevalence (and intensity) in these sentinel sites pre-MDA of S. mansoni was 69.0% (170.8 epg), hookworm: 41.7% (71.7 epg), Ascaris lumbricoides: 1.8% and Trichuris trichiura: 3.8%. Six months post MDA, the findings were S. mansoni: 38.2% (47.3 epg) and hookworm: 14.5% (8.7 epg), representing a reduction from pre-MDA levels of 44.6% (65.2%) and 72.3% (87.9%) respectively. The proportion of children who were moderately or heavily infected with S. mansoni fell from 35.6% pre MDA to 9.9% post MDA. Conclusions Significant reduction in S. mansoni and hookworm infection was achieved by this first round MDA in school-going children in Sierra Leone. This reduction in infection burden can potentially contribute to a reduction of morbidity, such as anaemia, in these children.
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Affiliation(s)
- Mary H Hodges
- Helen Keller International, PO Box 369, Freetown, Sierra Leone.
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Parasites or cohabitants: cruel omnipresent usurpers or creative "éminences grises"? J Parasitol Res 2011; 2011:214174. [PMID: 21785696 PMCID: PMC3140032 DOI: 10.1155/2011/214174] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 04/06/2011] [Indexed: 12/31/2022] Open
Abstract
This paper presents many types of interplays between parasites and the host, showing the history of parasites, the effects of parasites on the outcome of wars, invasions, migrations, and on the development of numerous regions of the globe, and the impact of parasitic diseases on the society and on the course of human evolution. It also emphasizes the pressing need to change the look at the parasitism phenomenon, proposing that the term “cohabitant” is more accurate than parasite, because every living being, from bacteria to mammals, is a consortium of living beings in the pangenome. Even the term parasitology should be replaced by cohabitology because there is no parasite alone and host alone: both together compose a new adaptive system: the parasitized-host or the cohabitant-cohabited being. It also suggests switching the old paradigm based on attrition and destruction, to a new one founded on adaptation and living together.
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Hodges M, Dada N, Wamsley A, Paye J, Nyorkor E, Sonnie M, Barnish G, Bockarie M, Zhang Y. Improved mapping strategy to better inform policy on the control of schistosomiasis and soil-transmitted helminthiasis in Sierra Leone. Parasit Vectors 2011; 4:97. [PMID: 21645386 PMCID: PMC3118383 DOI: 10.1186/1756-3305-4-97] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 06/06/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Schistosomiasis and soil-transmitted helminthiasis (STH) are endemic in Sierra Leone confirmed by national mapping in 2008. To better inform planning of preventive chemotherapy strategy, another survey was conducted before mass drug administration (MDA) in seven districts according to the mapping results or local knowledge. Fifty-nine chiefdoms and one school in every chiefdom were selected. Thirty school children aged 9-14 years from each school (total: 1760) were examined by parasitological methods for infection with Schistosoma mansoni and STHs. RESULTS The overall prevalence of S. mansoni was 40.2% (95% confidence interval (CI): 37.9-42.5%), particularly in Kailahun (63.3%), Kenema (46.7%), Koinadugu (41.9%) and Kono (71.7%). The results demonstrated the focal distribution of S. mansoni in Bo, Tonkolili and Bombali districts with prevalence ranging from 0.0-63.3%, 3.3-90.0% and 0.0-67.9% respectively. The arithmetic mean intensity of S. mansoni infection was 95.4 epg (95% CI: 61.4-129.5 epg), Heavy mean intensity of infection was found in Kailahun (120.2 epg), Kenema (104.5 epg), Koinadugu (112.3 epg) and Kono (250.3 epg). Heavy or moderate infection with S. mansoni occurred in 20.7% of children examined. Hookworm prevalence was moderate: 31.2% (95% CI: 29.1-33.4%), but high in Bo (50.0%) and Tonkolili (56.7%). Hookworm intensity of infection was light with a mean epg of 53.0 (95% CI: 38.4-67.7 epg). Prevalence and intensity of Ascaris lumbricoides (1.5%, 17.8 epg) and Trichuris trichiura (2.5%, 20.3 epg) was low. CONCLUSIONS The prediction by previous spatial analysis that S. mansoni was highly endemic across north-eastern Sierra Leone was confirmed with a significant proportion of children heavily or moderately infected. The distribution of S. mansoni in Bo, Tonkolili and Bombali districts ranged widely, highlighting the importance of considering the nature of focal transmission in national mapping exercises. These results were used to refine the MDA for schistosomiasis control to chiefdom implementation units rather than the entire district in these 3 districts. The survey demonstrated that sufficient number of survey sites for schistosomiasis mapping in each district should be used to provide a better national planning of MDA activities, and that it is affordable with the contributions from all parties involved and national resources mobilized.
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Affiliation(s)
- Mary Hodges
- Helen Keller International, Freetown, Sierra Leone.
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Schilter HC, Pereira ATM, Eschenazi PD, Fernandes A, Shim D, Sousa ALS, Teixeira MM, Negrão-Corrêa D. Regulation of immune responses to Strongyloides venezuelensis challenge after primary infection with different larvae doses. Parasite Immunol 2010; 32:184-92. [PMID: 20398181 DOI: 10.1111/j.1365-3024.2009.01176.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Nematode infections are generally followed by high rates of reinfection, leading to elevated prevalence in endemic areas. Therefore, the effective control of nematode infections depends on understanding the induction and regulation of protective mechanisms. However, most experimental models for protective immune response against nematodes use high parasite exposure, not always reflecting what occurs naturally in human populations. In this study, we tested whether infecting mice with different Strongyloides venezuelensis larvae loads would affect protective responses against reinfection. Interestingly, we found that a previous infection with 10-500 larvae conferred high rate of protection against reinfection with S. venezuelensis in mice, by destroying large numbers of migrating larvae. However, low-dose priming did not abolish adult worm maturation, as detected in high-dose primed group. Results also indicated that a previous low-dose infection delayed the development of cellular infiltrate, while a high inoculum rapidly induced these inflammatory features. Cytokine production by splenocyte cultures of challenge infected mice demonstrated that low-dose priming had increased production of IL-4 and IFN-gamma, while high-dose induced IL-4 production but not IFN-gamma. Our data support the hypothesis that low-dose nematode infection does not induce a polarized type-2 immune response, allowing adult worm survival.
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Affiliation(s)
- H C Schilter
- Department of Parasitology, Biological Science Institute of the Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
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Brooker S. Estimating the global distribution and disease burden of intestinal nematode infections: adding up the numbers--a review. Int J Parasitol 2010; 40:1137-44. [PMID: 20430032 DOI: 10.1016/j.ijpara.2010.04.004] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 04/15/2010] [Accepted: 04/15/2010] [Indexed: 02/05/2023]
Abstract
Intestinal nematode infections are among the most common infections of humans in developing countries, but precise estimates of the populations at risk of infection, morbidity and mortality are difficult to derive. Careful evaluation of the global distribution and disease burden of nematodes is essential to determine the cost-effectiveness of control and ensure that control programmes are focused appropriately. In turn, understanding the disease burden depends on a summary measure of health as well as reliable data on risks of infection, morbidity and mortality. This review provides an overview of data sources and methods adopted in the Global Burden of Disease study to estimate the burden of intestinal nematodes, including the empirical and modelling challenges in its estimation. Particular attention is paid to efforts to improve our ability to define at-risk populations, based on a Global Atlas of Helminth Infection, and to better estimate attributable morbidity.
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Affiliation(s)
- Simon Brooker
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, United Kingdom.
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Cost-effectiveness of a successful schistosomiasis control programme in Cambodia (1995-2006). Acta Trop 2010; 113:279-84. [PMID: 19962364 DOI: 10.1016/j.actatropica.2009.11.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Revised: 11/19/2009] [Accepted: 11/28/2009] [Indexed: 11/20/2022]
Abstract
Following preventive chemotherapy covering the entire population in the two endemic regions in Cambodia, the prevalence of schistosomiasis dropped from 77% in 1995 to 0.5% in 2003. The study presented here reports on the running cost of the control programme, and evaluates its cost-effectiveness and cost-benefit. Financial costs were assessed using data taken from the annual reports of the National Center for Malaria Control, the Cambodian institution responsible for the control activities. Other data were collected from interviews with provincial and district staff. The analysis was conducted from the point of views of the Cambodian Ministry of Health and that of the society, and the comparison was undertaken using the "do-nothing" option. The cost to treat an individual for the 9 years period of the implementation phase was 9.22 USD (1.02 per year), the cost for each severe infection avoided was 61.50 USD and 6531 USD for each death avoided. The drug cost corresponds on average to 17.34% of the programme's implementation cost. The cost of bringing one severely infected individual of productive age to complete productivity, was estimated at 114 USD and for 1 USD invested in the programme the return in increased productivity, for the economic system, was estimated to be 3.85 USD. The control programme demonstrated significant economical advantages. However, its costs are too high to be entirely supported by the Cambodian Ministry of Health.
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Parasites and poverty: the case of schistosomiasis. Acta Trop 2010; 113:95-104. [PMID: 19962954 DOI: 10.1016/j.actatropica.2009.11.012] [Citation(s) in RCA: 387] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 07/10/2009] [Accepted: 11/23/2009] [Indexed: 11/21/2022]
Abstract
Simultaneous and sequential transmission of multiple parasites, and their resultant overlapping chronic infections, are facts of life in many underdeveloped rural areas. These represent significant but often poorly measured health and economic burdens for affected populations. For example, the chronic inflammatory process associated with long-term schistosomiasis contributes to anaemia and undernutrition, which, in turn, can lead to growth stunting, poor school performance, poor work productivity, and continued poverty. To date, most national and international programs aimed at parasite control have not considered the varied economic and ecological factors underlying multi-parasite transmission, but some are beginning to provide a coordinated approach to control. In addition, interest is emerging in new studies for the re-evaluation and recalibration of the health burden of helminthic parasite infection. Their results should highlight the strong potential of integrated parasite control in efforts for poverty reduction.
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French AT, Knight PA, Smith WD, Pate JA, Miller HRP, Pemberton AD. Expression of three intelectins in sheep and response to a Th2 environment. Vet Res 2009; 40:53. [PMID: 19549487 PMCID: PMC2733327 DOI: 10.1051/vetres/2009035] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Accepted: 06/22/2009] [Indexed: 01/11/2023] Open
Abstract
Sheep intelectin1 and sheep intelectin3 (sITLN1 and sITLN3) were cloned and sequenced. The amino acid sequences of sITLN1 and sITLN3 shared 86% and 91% homology with the previously cloned sheep intelectin2 (sITLN2), respectively. Expression of sITLN1 and sITLN3 transcript was demonstrated in abomasum, lung, colon and gastric lymph node, terminal rectum, skin, jejunum, mesenteric lymph node, ileal peyer’s patches, brain, kidney, liver, spleen, skin, ear pinna, heart and ovary in normal sheep tissues. sITLN2 transcript expression was restricted to the abomasal mucosa in normal sheep tissues. Using a non selective chicken anti-intelectin antibody, tissue intelectin protein was demonstrated in mucus neck cells in the abomasum, mucus cells in the colon, free mucus in ileum, goblet cells in the lung, small intestinal epithelium and brush border, epidermal layer of the skin and skin sebaceous glands. The expression of the three sITLN transcripts was examined in two nematode infections in sheep known to induce a Th2 response; a Teladorsagia circumcincta challenge infection model and a Dictyocaulus filaria natural infection. The three sITLN were absent in unchallenged naïve lambs and present in the abomasal mucosa of both naïve and immune lambs following T. circumcincta challenge infection. Upregulation of sITLN2 and sITLN3 was shown in sheep lung following D. filaria natural infection. Intelectins may play an important role in the mucosal response to nematode infections in ruminants.
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Affiliation(s)
- Anne T French
- Royal (Dick) School of Veterinary Studies, Division of Veterinary Clinical Sciences University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian, EH25 9RG, United Kingdom.
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Dea-Ayuela MA, Rama-Iñiguez S, Torrado-Santiago S, Bolas-Fernandez F. Microcapsules formulated in the enteric coating copolymer Eudragit L100 as delivery systems for oral vaccination against infections by gastrointestinal nematode parasites. J Drug Target 2008; 14:567-75. [PMID: 17050122 DOI: 10.1080/10611860600849464] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Microcapsules using the copolymer of methacrylic acid (Eudragit L100) were formulated for oral delivery of vaccines against the enteral/parenteral nematode parasite Trichinella spiralis. Antigenic preparations from first stage larvae (L1) of T. spiralis were microencapsulated in Eudragit L100. The microcapsules prepared by the spray drying method were resistant to acid pH, although the antigen was rapidly released under neutral and basic environmental conditions. The native protein conformation and biological activity was preserved in the microcapsules, as assessed by SDS-PAGE and ELISA. When administered to NIH mice, the antigen loaded microcapsules protected against infection by T. spiralis at both the intestinal and muscular levels, the worm burden diminishing by 45.58 and 53.33%, respectively. Furthermore, following administration of the microparticles an increase of the serum IgG1 response, a marker for the Th2 type response, was evident. These results indicate that microcapsules formulated with anionic biocompatible polymers such as Eudragit may be useful for oral vaccination against nematode infections.
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Affiliation(s)
- Maria A Dea-Ayuela
- Departamento de Parasitología, Facultad de Farmacia, Universidad Complutense, Plaza de Ramón y Cajal s/n, Ciudad Universitaria, 28040, Madrid, Spain
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Pullan R, Brooker S. The health impact of polyparasitism in humans: are we under-estimating the burden of parasitic diseases? Parasitology 2008; 135:783-94. [PMID: 18371242 PMCID: PMC2645487 DOI: 10.1017/s0031182008000346] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Parasitic infections are widespread throughout the tropics and sub-tropics, and infection with multiple parasite species is the norm rather than the exception. Despite the ubiquity of polyparasitism, its public health significance has been inadequately studied. Here we review available studies investigating the nutritional and pathological consequences of multiple infections with Plasmodium and helminth infection and, in doing so, encourage a reassessment of the disease burden caused by polyparasitism. The available evidence is conspicuously sparse but is suggestive that multiple human parasite species may have an additive and/or multiplicative impact on nutrition and organ pathology. Existing studies suffer from a number of methodological limitations and adequately designed studies are clearly necessary. Current methods of estimating the potential global morbidity due to parasitic diseases underestimate the health impact of polyparasitism, and possible reasons for this are presented. As international strategies to control multiple parasite species are rolled-out, there is a number of options to investigate the complexity of polyparasitism, and it is hoped that that the parasitological research community will grasp the opportunity to understand better the health of polyparasitism in humans.
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Affiliation(s)
- R Pullan
- Department of Infectious and Tropical Disease, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK.
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Asymmetries of poverty: why global burden of disease valuations underestimate the burden of neglected tropical diseases. PLoS Negl Trop Dis 2008; 2:e209. [PMID: 18365036 PMCID: PMC2267491 DOI: 10.1371/journal.pntd.0000209] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Accepted: 02/05/2008] [Indexed: 11/20/2022] Open
Abstract
The disability-adjusted life year (DALY) initially appeared attractive as a health metric in the Global Burden of Disease (GBD) program, as it purports to be a comprehensive health assessment that encompassed premature mortality, morbidity, impairment, and disability. It was originally thought that the DALY would be useful in policy settings, reflecting normative valuations as a standardized unit of ill health. However, the design of the DALY and its use in policy estimates contain inherent flaws that result in systematic undervaluation of the importance of chronic diseases, such as many of the neglected tropical diseases (NTDs), in world health. The conceptual design of the DALY comes out of a perspective largely focused on the individual risk rather than the ecology of disease, thus failing to acknowledge the implications of context on the burden of disease for the poor. It is nonrepresentative of the impact of poverty on disability, which results in the significant underestimation of disability weights for chronic diseases such as the NTDs. Finally, the application of the DALY in policy estimates does not account for the nonlinear effects of poverty in the cost-utility analysis of disease control, effectively discounting the utility of comprehensively treating NTDs. The present DALY framework needs to be substantially revised if the GBD is to become a valid and useful system for determining health priorities.
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Abstract
OBJECTIVES To summarize new knowledge on the range of disease due to chronic schistosomiasis and examine the debilitating burden of both light and heavy infection; to outline goals of disease prevention, including current age-targeted strategies and more extended programmes aimed at preventing transmission. METHODS A systematic search of 2004-2007 papers via PUBMED and related databases using 'schistosom' and disability- or treatment-related subject headings. Reports were independently reviewed for inclusion. RESULTS Sixty-eight papers met review objectives. These suggest new evidence for a causative link between schistosome infection, antiparasite inflammation, and risk for anaemia, growth stunting and undernutrition in affected populations, as well as exacerbation of co-infections and impairment of cognitive development and work capacity. Formal quality-of-life assessment defines a significant 9.5-24% disability with the most aggressive schistosome species, Schistosoma japonicum. DISCUSSION Schistosomiasis represents a serious but under-recognized disease burden for many developing countries. Infection (and not intensity of infection) should be considered the defining feature of morbidity formation. Links between infection and long-term disabilities reduce the chances of combating rural poverty. Changes in our appreciation of schistosomiasis-related disease burden means it is no longer appropriate to leave infected persons untreated, and newer approaches to control should focus on preventing transmission.
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Affiliation(s)
- Charles H King
- Center for Global Health and Diseases, Case Western Reserve University School of Medicine 10900 Euclid Avenue, Cleveland, Ohio 44106-7286, USA.
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Stepek G, Buttle DJ, Duce IR, Behnke JM. Human gastrointestinal nematode infections: are new control methods required? Int J Exp Pathol 2006; 87:325-41. [PMID: 16965561 PMCID: PMC2517378 DOI: 10.1111/j.1365-2613.2006.00495.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Gastrointestinal (GI) nematode infections affect 50% of the human population worldwide, and cause great morbidity as well as hundreds of thousands of deaths. Despite modern medical practices, the proportion of the population infected with GI nematodes is not falling. This is due to a number of factors, the most important being the lack of good healthcare, sanitation and health education in many developing countries. A relatively new problem is the development of resistance to the small number of drugs available to treat GI nematode infections. Here we review the most important parasitic GI nematodes and the methods available to control them. In addition, we discuss the current status of new anthelmintic treatments, particularly the plant cysteine proteinases from various sources of latex-bearing plants and fruits.
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Affiliation(s)
- Gillian Stepek
- School of Biology, University of Nottingham, Nottingham, UK
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Grigorenko EL, Sternberg RJ, Jukes M, Alcock K, Lambo J, Ngorosho D, Nokes C, Bundy DA. Effects of antiparasitic treatment on dynamically and statically tested cognitive skills over time. JOURNAL OF APPLIED DEVELOPMENTAL PSYCHOLOGY 2006. [DOI: 10.1016/j.appdev.2006.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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