1
|
Hon KL, Leung AKC. An update on the current and emerging pharmacotherapy for the treatment of human ascariasis. Expert Opin Pharmacother 2024. [PMID: 38372051 DOI: 10.1080/14656566.2024.2319686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 02/13/2024] [Indexed: 02/20/2024]
Abstract
INTRODUCTION Globally, Ascaris lumbricoides is the commonest helminthic infection that affects people in underdeveloped countries and returning immigrants in industrialized nations. This article aims to provide latest updates on the epidemiology, clinical manifestations, and pharmacotherapy of ascariasis. AREAS COVERED A PubMed search was conducted using Clinical Queries and the key terms 'human ascariasis' OR 'Ascaris lumbricoides.' Ascaris lumbricoides is highly endemic in tropical and subtropic regions and among returning immigrants in industrialized nations. Predisposing factors include poor sanitation and poverty. The prevalence is greatest in young children. Most infected patients are asymptomatic. Patients with A. lumbricoides infection should be treated with anti-helminthic drugs to prevent complications from migration of the worm. Mebendazole and albendazole are indicated for children and nonpregnant women. Pregnant individuals should be treated with pyrantel pamoate. EXPERT OPINION Cure rates with anthelmintic treatment are high. No emerging pharmacotherapy can replace these existing drugs of good efficacy, safety profile and low cost for public health. It is opinioned that advances in the management of ascariasis include diagnostic accuracy at affordable costs, Emodepside is highly effective in single doses against ascarids in mammals and in human trials. The drug could be registered for human use in multiple neglected tropical diseases.
Collapse
Affiliation(s)
- Kam Lun Hon
- Department of Paediatrics, The Chinese University of Hong Kong, and Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, Hong Kong, China
| | - Alexander K C Leung
- Department of Pediatrics, The University of Calgary and the Alberta Children's Hospital, Calgary, Alberta, Canada
| |
Collapse
|
2
|
Shanebeck KM, Besson AA, Lagrue C, Green SJ. The energetic costs of sub-lethal helminth parasites in mammals: a meta-analysis. Biol Rev Camb Philos Soc 2022; 97:1886-1907. [PMID: 35678252 DOI: 10.1111/brv.12867] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 05/02/2022] [Accepted: 05/05/2022] [Indexed: 01/07/2023]
Abstract
Parasites, by definition, have a negative effect on their host. However, in wild mammal health and conservation research, sub-lethal infections are commonly assumed to have negligible health effects unless parasites are present in overwhelming numbers. Here, we propose a definition for host health in mammals that includes sub-lethal effects of parasites on the host's capacity to adapt to the environment and maintain homeostasis. We synthesized the growing number of studies on helminth parasites in mammals to assess evidence for the relative magnitude of sub-lethal effects of infection across mammal taxa based on this expanded definition. Specifically, we develop and apply a framework for organizing disparate metrics of parasite effects on host health and body condition according to their impact on an animal's energetic condition, defined as the energetic burden of pathogens on host physiological and behavioural functions that relate directly to fitness. Applying this framework within a global meta-analysis of helminth parasites in wild, laboratory and domestic mammal hosts produced 142 peer-reviewed studies documenting 599 infection-condition effects. Analysing these data within a multiple working hypotheses framework allowed us to evaluate the relative weighted contribution of methodological (study design, sampling protocol, parasite quantification methods) and biological (phylogenetic relationships and host/parasite life history) moderators to variation in the magnitude of health effects. We found consistently strong negative effects of infection on host energetic condition across taxonomic groups, with unusually low heterogeneity in effect sizes when compared with other ecological meta-analyses. Observed effect size was significantly lower within cross-sectional studies (i.e. observational studies that investigated a sub-set of a population at a single point in time), the most prevalent methodology. Furthermore, opportunistic sampling led to a weaker negative effect compared to proactive sampling. In the model of host taxonomic group, the effect of infection on energetic condition in carnivores was not significant. However, when sampling method was included, it explained substantial inter-study variance; proactive sampling showing a strongly significant negative effect while opportunistic sampling detected only a weak, non-significant effect. This may partly underlie previous assumptions that sub-lethal parasites do not have significant effects on host health. We recommend future studies adopt energetic condition as the framework for assessing parasite effects on wildlife health and provide guidelines for the selection of research protocols, health proxies, and relating infection to fitness.
Collapse
Affiliation(s)
- Kyle M Shanebeck
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, Canada
| | - Anne A Besson
- Department of Zoology, University of Otago, 340 Great King Street, Dunedin, 9016, New Zealand
| | - Clement Lagrue
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, Canada.,Department of Zoology, University of Otago, 340 Great King Street, Dunedin, 9016, New Zealand.,Department of Conservation, 265 Princes Street, Dunedin, 9016, New Zealand
| | - Stephanie J Green
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, Canada
| |
Collapse
|
3
|
Al-Mekhlafi HM, Al-Maktari MT, Jani R, Ahmed A, Anuar TS, Moktar N, Mahdy MAK, Lim YAL, Mahmud R, Surin J. Burden of Giardia duodenalis infection and its adverse effects on growth of schoolchildren in rural Malaysia. PLoS Negl Trop Dis 2013; 7:e2516. [PMID: 24205426 PMCID: PMC3814875 DOI: 10.1371/journal.pntd.0002516] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 09/22/2013] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Giardia duodenalis infection and malnutrition are still considered as public health problems in many developing countries especially among children in rural communities. This study was carried out among Aboriginal (Orang Asli) primary schoolchildren in rural peninsular Malaysia to investigate the burden and the effects of Giardia infection on growth (weight and height) of the children. METHODS/FINDINGS Weight and height of 374 children aged 7-12 years were assessed before and after treatment of Giardia infection. The children were screened for Giardia parasite using trichrome staining technique. Demographic and socioeconomic data were collected via face-to-face interviews using a pre-tested questionnaire. Overall, 22.2% (83/374) of the children were found to be infected with Giardia. Nutritional status of children was assessed and the results showed that the mean weight and height were 23.9 kg (95% CI = 23.3, 24.5) and 126.6 cm (95% CI = 125.6, 127.5), respectively. Overall, the prevalence of severe underweight, stunting and wasting were 28.3%, 23.8% and 21.0%, respectively. Multiple linear regression analyses showed sex, Giardia infection and household monthly income as the significant determinants of weight while sex and level of mother's education were the significant determinants of height. Weight and height were assessed at 3 and 6 months after treatment of Giardia infection. It was found that Giardia infection has a significant association with the weight of children but not with height. CONCLUSIONS/SIGNIFICANCE This study reveals high prevalence of Giardia infection and malnutrition among Aboriginal children in rural Malaysia and clearly highlights an urgent need to identify integrated measures to control these health problems in the rural communities. Essentially, proper attention should be given to the control of Giardia infection in Aboriginal communities as this constitutes one of the strategies to improve the nutritional status of Aboriginal children.
Collapse
Affiliation(s)
- Hesham M. Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Medical Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Mohamed T. Al-Maktari
- Department of Medical Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Rohana Jani
- Department of Applied Statistics, Faculty of Economics and Administration, University of Malaya, Kuala Lumpur, Malaysia
| | - Abdulhamid Ahmed
- Department of Biology, Faculty of Natural and Applied Sciences, Umaru Musa Yar'adua University, Katsina. Katsina State, Nigeria
| | - Tengku Shahrul Anuar
- Department of Medical Laboratory Technology, Faculty of Health Sciences, Universiti Teknologi MARA (Puncak Alam Campus), Selangor, Malaysia
| | - Norhayati Moktar
- Department of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Mohammed A. K. Mahdy
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Medical Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Yvonne A. L. Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Johari Surin
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
4
|
|
5
|
Hesham Al-Mekhlafi M, Surin J, Atiya A, Ariffin W, Mohammed Mahdy A, Che Abdullah H. Pattern and predictors of soil-transmitted helminth reinfection among aboriginal schoolchildren in rural Peninsular Malaysia. Acta Trop 2008; 107:200-4. [PMID: 18582430 DOI: 10.1016/j.actatropica.2008.05.022] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 05/09/2008] [Accepted: 05/29/2008] [Indexed: 10/22/2022]
Abstract
Data on soil-transmitted helminth (STH) infections and reinfection among Orang Asli (aborigine) schoolchildren and their nutritional and socioeconomic status were analyzed to investigate the pattern and the possible predictors of STH reinfection. In this longitudinal study, 120 (60 males and 60 females) Orang Asli primary schoolchildren aged 7-12 years and living in remote areas in Pos Betau, Kuala Lipis, Pahang were screened for the presence of STH using modified cellophane thick smear and Harada Mori techniques. The overall prevalence of ascariasis, trichuriasis and hookworm infections were 65.8, 97.5 and 10.8%, respectively. After complete deworming with a 3-day course of 400mg/daily of albendazole tablets, children were re-examined at 3 and 6 months from baseline. The reinfection rate, by one or more of STH species, at 3 months after deworming was high (49.5%) while 79.6% of the children were reinfected at 6 months after deworming. Logistic regression analyses showed that females, stunted children and those living in houses without toilets had significantly higher reinfection rates than others at 3 months (P<0.05). At 6 months, maternal employment status emerged as another predictor where children of working mothers had significantly higher reinfection rates (P=0.026). In conclusion, reinfection rate of STH is high and thus necessitates frequent and periodic deworming among children. Public health personnel need to re-look at the current control measures and identify innovative and integrated ways in order to reduce STH significantly in the rural communities.
Collapse
|
6
|
Al-Mekhlafi MH, Azlin M, Aini UN, Shaik A, Sa’iah A, Norhayati M. Prevalence and predictors of low serum retinol and hypoalbuminaemia among children in rural Peninsular Malaysia. Trans R Soc Trop Med Hyg 2007; 101:1233-40. [DOI: 10.1016/j.trstmh.2007.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Revised: 09/06/2007] [Accepted: 09/06/2007] [Indexed: 10/22/2022] Open
|
7
|
Association between Unhealthful Eating Patterns and Unfavorable Overall School Performance in Children. ACTA ACUST UNITED AC 2007; 107:1935-43. [DOI: 10.1016/j.jada.2007.08.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2006] [Indexed: 11/18/2022]
|
8
|
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.
Collapse
Affiliation(s)
- Gillian Stepek
- School of Biology, University of Nottingham, Nottingham, UK
| | | | | | | |
Collapse
|
9
|
Held MR, Bungiro RD, Harrison LM, Hamza I, Cappello M. Dietary iron content mediates hookworm pathogenesis in vivo. Infect Immun 2006; 74:289-95. [PMID: 16368983 PMCID: PMC1346670 DOI: 10.1128/iai.74.1.289-295.2006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hookworm infection is associated with growth delay and iron deficiency anemia in developing countries. A series of experiments were designed in order to test the hypothesis that host dietary iron restriction mediates susceptibility to hookworm infection using the hamster model of Ancylostoma ceylanicum. Animals were maintained on diets containing either 10 ppm iron (iron restricted) or 200 ppm iron (standard/high iron), followed by infection with A. ceylanicum third-stage larvae. Infected animals fed the standard diet exhibited statistically significant growth delay and reduced blood hemoglobin levels compared to uninfected controls on day 20 postinfection. In contrast, no statistically significant differences in weight or hemoglobin concentration were observed between infected and uninfected animals fed the iron-restricted diet. Moreover, iron-restricted animals were observed to have reduced intestinal worm burdens on day 10 and day 20 postinfection compared to those of animals maintained on the standard/high-iron diet. In a subsequent study, animals equilibrated on diets containing a range of iron levels (10 ppm, 40 ppm, 100 ppm, or 200 ppm) were infected with A. ceylanicum and followed for evidence of hookworm disease. Infected animals from the intermediate-dietary iron (40- and 100-ppm) groups exhibited greater weight loss and anemia than those in the low (10-ppm)- or high (200-ppm)-iron diet groups. Mortality was also significantly higher in the intermediate-dietary-iron groups. These data suggest that severe dietary iron restriction impairs hookworm development in vivo but that moderate iron restriction enhances host susceptibility to severe disease.
Collapse
Affiliation(s)
- Melissa R Held
- Program in International Child Health, Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520, USA
| | | | | | | | | |
Collapse
|
10
|
Abstract
The common roundworm, Ascaris lumbricoides, is probably the most prevalent human intestinal helminth. Previous estimates of world prevalence range from around 650 million to 1000 million. By a detailed literature search, David Crompton now confirms the upper figure - estimating a world prevalence of 1008 million representing about 22% of the world population. The infection is known from 153 out of 218 recognized countries.
Collapse
Affiliation(s)
- D W Crompton
- Department of Zoology, University of Glasgow Glasgow G 12 8QQ, UK
| |
Collapse
|
11
|
Gunawardena GSA, Karunaweera ND, Ismail MM. Wet-days: are they better indicators of Ascaris infection levels? J Helminthol 2005; 78:305-10. [PMID: 15575986 DOI: 10.1079/joh2004252] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Seasonal variation in a particular area may influence the occurrence of helminth infections and determining such fluctuations may help to maximize the beneficial effects of mass treatment. This study determined the seasonal variations in infection levels of Ascaris lumbricoides between March 2000 and June 2001 in two selected low-country plantations. Four hundred and seventy seven persons aged between 2 and 74 years (median 13) participated. Stools were tested using the Kato-Katz method and the prevalence and intensity of infection determined. All persons were treated with a single dose of mebendazole. Monthly follow-ups were undertaken with similar stool examinations and treatment given if found positive. Infection and re-infection rates were calculated each month. Rainfall and temperature were recorded each day. Total rainfall, number of wet-days and mean temperature was calculated for each month. The prevalence of Ascaris infection was 53.4% and 51.0% at Maliboda and Ayr estates respectively. Highest infection and re-infection rates at Maliboda (37.7%, 37.2%) occurred in June and at Ayr (13.3%, 25.9%) in October 2000 respectively. During the study period, the mean rainfall was 28.1 cm (range 7.4-63.9 cm) and mean temperature 27.6 degrees C (range 22.1 degrees -34.4 degrees C). Significant correlations (P<0.05) were found between the re-infection rate and rainfall, temperature and the number of wet-days. Similar correlations were observed with the infection rate and temperature and the number of wet-days. Ascaris infections were found to correlate significantly only with the number of wet-days in a month (P<0.01). Thus, the number of wet-days appears to be a better indicator of Ascaris infections than total rainfall or mean temperature.
Collapse
Affiliation(s)
- G S A Gunawardena
- Department of Parasitology, Faculty of Medicine, University of Colombo, PO Box 271, Kynsey Road, Colombo 8, Sri Lanka.
| | | | | |
Collapse
|
12
|
Muniz-Junqueira MI, Queiroz EFO. Relationship between protein-energy malnutrition, vitamin A, and parasitoses in living in Brasília. Rev Soc Bras Med Trop 2002; 35:133-41. [PMID: 12011921 DOI: 10.1590/s0037-86822002000200002] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It is still controversial whether intestinal parasitic infections can influence the nutritional status of children. The relationship between protein-energy malnutrition, vitamin A and parasitic infections was evaluated in 124 children. The food intake estimated by recall method was generally low and poor. Seventy five percent of the children were infected with intestinal parasites. The mean+/-SD weight-for-age and height-for-age Z-score were skewed one standard deviation to the left, when compared to normal standards. An association was found between protein-energy malnutrition and Giardia lamblia, but not with Ascaris lumbricoides or Hymenolepis nana infection. Only Giardia-infected children had a decreased weight-for-age and weight-for-height Z-score. Hypovitaminosis A was a major nutritional problem, but no relationship between this deficiency and parasitic infection was found. Our data indicate that low and poor food intake were the major cause of protein-energy malnutrition among the children, and except for Giardia, this was not influenced by parasitic infections.
Collapse
Affiliation(s)
- Maria Imaculada Muniz-Junqueira
- Laboratório de Imunologia Celular, Area de Patologia, Faculdade de Medicina, Universidade de Brasília, Brasília, DF, Brasil.
| | | |
Collapse
|
13
|
Váradyová Z, Zelenák I, Siroka P, Dubinský P. In vitro fermentation of cellulosis amorphous and meadow hay in experimentally Ascaris suum-infected lambs. Small Rumin Res 2001; 40:155-164. [PMID: 11295398 DOI: 10.1016/s0921-4488(01)00170-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of this experiment was to determine the effect of rumen inocula from experimentally Ascaris suum (AS)-infected lambs on cellulose amorphous (CA) and meadow hay (MH) used as substrates during 72h incubation in vitro. The rumen inocula were obtained post-mortem from eight lambs that had been experimentally infected with 1000 AS eggs per lamb daily for 3 weeks. Samples of rumen inocula were obtained from the lambs weekly throughout the experiment for 8 weeks. Two lambs were kept as uninfected control animals. The substrates were incubated together with buffered rumen fluid in sealed fermentation bottles. In vitro dry matter degradability (IVDMD), total gas, methane and total and individual fatty acid (VFA) for both incubated substrates were measured and compared by the pressure transducer technique. Comparison of the values for the controls, total gas, methane and VFA revealed significant differences (P<0.05, P<0.01, P<0.001, respectively) for both substrates. Pronounced differences (P<0.001) were also found between CA and MH especially for IVDMD, total gas and total VFA production. A decrease (P<0.001) of IVDMD, total gas, methane and total VFA was observed from week 6 to week 8. Restriction of fermentation was evident from week 7 to week 8. The results suggest that the functional damage arising from pathological lesions within the parasite-infected organs considerably affected the fermentation parameters of the incubated substrates.
Collapse
Affiliation(s)
- Z Váradyová
- Institute of Animal Physiology, Slovak Academy of Sciences, Soltésovej 4-6, 040 01, Kosice, Slovak Republic
| | | | | | | |
Collapse
|
14
|
Northrop-Clewes CA, Rousham EK, Mascie-Taylor CN, Lunn PG. Anthelmintic treatment of rural Bangladeshi children: effect on host physiology, growth, and biochemical status. Am J Clin Nutr 2001; 73:53-60. [PMID: 11124750 DOI: 10.1093/ajcn/73.1.53] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The effect of helminth infestation on the nutrition, growth, and physiology of the host is still poorly understood. Anthelmintic treatment of children in developing countries has had varying success in terms of growth improvements. OBJECTIVE The objective of this study was to assess the effect of regular deworming on child growth, physiology, and biochemical status. DESIGN The study was a 12-mo longitudinal intervention in 123 Bangladeshi children aged 2-5 y. Treatment (mebendazole) or placebo tablets were administered every 2 mo for 8 mo and again at 12 mo. Weight, height, midupper arm circumference, intestinal permeability, plasma albumin, alpha(1)-antichymotrypsin, and total protein concentration were assessed every 2 mo. RESULTS Treatment with mebendazole reduced the prevalence of Ascaris lumbricoides from 78% to 8%, of Trichuris trichiura from 65% to 9%, and of hookworm from 4% to 0%. There was no significant difference in the growth of treated children compared with those given placebo tablets. No changes in intestinal permeability or plasma albumin were observed after deworming. Significant decreases in total protein (P<0.001) and alpha(1)-antichymotrypsin (P<0.001) were observed in the treatment group, indicating possible reductions in inflammation and immunoglobulin concentration after deworming. A significant increase in the prevalence of Giardia intestinalis (from 4% to 49%) in the treatment group was associated with a short-term reduction in weight (P = 0.02) and higher intestinal permeability (P <0.001) in infected subjects. No long-term effects of G. intestinalis on growth were observed. CONCLUSION Low-intensity helminth infections, predominantly of A. lumbricoides and T. trichiura, do not contribute significantly to the poor growth and biochemical status of rural Bangladeshi children.
Collapse
Affiliation(s)
- C A Northrop-Clewes
- Human Nutrition Research Group, School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | | | | | | |
Collapse
|
15
|
Abstract
The interactions between host nutrition and parasitism in ruminants are viewed within a framework that accounts for the allocation of scarce nutrient resources, such as energy and protein, between the various competing body functions of the host. These include functions that are the direct result of parasitism. Since it is proposed that the host gives priority to the reversal of the pathophysiological consequences of parasitism over other body functions, it is to be expected that improved nutrition will always lead to improved resilience. On the other hand, it is proposed that the function of growth, pregnancy and lactation are prioritised over the expression of immunity. Thus, improved nutrition may affect the degree of expression of immunity during these phases. The framework is useful at highlighting areas of future research on host/parasite/nutrition interactions. Its suggestions can account for the observations of the periparturient relaxation of immunity in reproducing females, as well as the reduction in worm burden in small ruminants supplemented with additional protein. Although developed for gastrointestinal nematodes in ruminants, the concepts of the framework should be applicable to the interactions of nutrition in other parasitic diseases.
Collapse
Affiliation(s)
- R L Coop
- Moredun Research Institute, Edinburgh, Scotland, UK
| | | |
Collapse
|
16
|
Tayeh A, Cairncross S. The impact of dracunculiasis on the nutritional status of children in South Kordofan, Sudan. ANNALS OF TROPICAL PAEDIATRICS 1996; 16:221-6. [PMID: 8893952 DOI: 10.1080/02724936.1996.11747830] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This paper assesses the indirect impact of dracunculiasis on the nutritional status of children under 6 years of age in South Kordofan, Sudan. Weight-for-height anthropometric measurement was used as a measure of the nutritional status of 774 children in 428 households. The indirect impact was investigated by comparing the nutritional status in 1988 of children in 'affected' households, where more than half the adult members had suffered from dracunculiasis in 1987, with children in other households. It was anticipated that when the otherwise able adult members of a households had dracunculiasis they were likely to be disabled by the disease and so prevented from fully performing their agricultural activities, so that the nutritional status of children in the same household would deteriorate in the following year. It was found that in 16.9% of the 136 'affected' households the children were wasted (with mean Z-scores of -2 or less), compared with only 6% of the other households.
Collapse
Affiliation(s)
- A Tayeh
- Department of Epidemiology and Population Sciences, London School of Hygiene and Tropical Medicine, UK
| | | |
Collapse
|
17
|
Machado MT, Machado TM, Yoshikae RM, Schmidt AL, Faria RDC, Paschoalotti MA, Barata RDC, Chieffi PP. Ascariasis in the subdistrict of Cavacos, municipality of alterosa (MG), Brazil: effect of mass treatment with albendazole on the intensity of infection. Rev Inst Med Trop Sao Paulo 1996; 38:265-71. [PMID: 9216107 DOI: 10.1590/s0036-46651996000400005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The clinical and epidemiologic aspects of infection with Ascaris lumbricoides were studied in a random stratified sample of the population of the subdistrict of Cavacos, municipality of Alterosa (Minas Gerais, Brazil). The effect of mass treatment with a single dose of albendazole on the prevalence and intensity of infection was also studied six months later in the same population. During the first phase of the study, a questionnaire was applied to 248 individuals to obtain information about the socioeconomic, sanitary and clinical conditions of the population surveyed. A total of 230 fecal samples were also examined by the Kato-Katz technique in order to determine the intensity of A. lumbricoides infection. Two hundred and two individuals were simultaneously submitted to blood counts and 70 children aged 12 years or less were evaluated for nutritional status. The presence of A. lumbricoides and other helminth eggs was also determined in 22 soil samples collected in the urban zone of Cavacos. Infection with enteroparasitic helminths was detected in 29.1% of the sample, with a predominance of A. lumbricoides (23.9%). Parasitism and/or intensity of A. lumbricoides infection were significantly correlated with age range (15 years or less), social class, sanitary and living conditions (water, sewage and domiciliary area per person), and presence of abdominal pain. However, these parameters were not correlated with nutritional status or hematocrit levels. During the second phase of the study, a slight but not statistically significant decrease in the prevalence of A. lumbricoides infection was detected after treatment with albendazole. However, an important and significant reduction in the amount of A. lumbricoides eggs eliminated through the feces was detected, indicating that the intensity of A. lumbricoides infection was lower in all the age ranges of the Cavacos population, especially among younger individuals, even six months after administration of the anthelminthic agent.
Collapse
Affiliation(s)
- M T Machado
- Faculdade de Ciências Médicas, Santa Casa de São Paulo, Brasil
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Abstract
Heavy infection with the geohelminth Trichuris trichiura causes the Trichuris dysentery syndrome (TDS). Growth retardation and anaemia are characteristic of TDS and both are associated with poor development. We have examined the growth and developmental responses to treatment in 19 children aged 27-84 months with TDS. Developmental levels (DQ) were measured with the Griffiths mental development scales. Compared with a control group matched for age, gender and neighbourhood, the TDS children initially had serious deficits in DQ (24 points, p < 0.001). After a year of anthelmintic treatment, the TDS children showed improvement in locomotor development (p < 0.001) compared with the controls. The TDS children also had initial deficits in height-for-age, weight-for-height, mid-upper arm circumference and haemoglobin levels. They caught up rapidly in indices of wasting (weight-for-height and mid-upper arm circumference) and showed steady improvement in height-for-age and haemoglobin levels. Catch-up in height was comparable to that of children recovering from coeliac disease. The importance of continuing prevention after initial treatment is highlighted.
Collapse
Affiliation(s)
- J E Callender
- Tropical Metabolism Research Unit, University of the West Indies, Mona, Kingston, Jamaica
| | | | | | | |
Collapse
|
19
|
Rousham EK, Mascie-Taylor CG. An 18-month study of the effect of periodic anthelminthic treatment on the growth and nutritional status of pre-school children in Bangladesh. Ann Hum Biol 1994; 21:315-24. [PMID: 8080233 DOI: 10.1080/03014469400003322] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
An 18-month study was conducted from February 1989 to August 1990 to examine the effect of regular deworming on child growth and nutritional status. A sample of 1402 children, from 2 to 6 years old, were divided into a treatment group and a control group. The 688 children in the treatment group received a 500 mg single dose of mebendazole, while the 714 children in the control group were given a placebo. Height, weight and mid-upper arm circumference (MUAC) were measured on monthly household visits. Growth was measured in terms of the change in height-for-age, weight-for-age, weight-for-height and MUAC over 18 months. The initial prevalence of infection was estimated from a random sample of 96 children (49 treated, 47 control). The initial overall prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm was 71, 44 and 10% respectively. The final prevalence of infection, estimated from a random sample of 265 children, was A. lumbricoides 6%, T. trichiura 6% and hookworm 2% in the mebendazole group compared with 64, 18 and 19% respectively in the placebo group. Despite the successful treatment of helminths, there was no significant improvement in the growth of treated children compared with their untreated counterparts in terms of the change in z-scores of height-for-age, weight-for-age, weight-for-height and MUAC. The factors which may have contributed to this outcome are discussed.
Collapse
Affiliation(s)
- E K Rousham
- Department of Biological Anthropology, University of Cambridge, UK
| | | |
Collapse
|
20
|
Environmental correlates of gastrointestinal parasitism in montane and lowland baboons in Natal, South Africa. INT J PRIMATOL 1993. [DOI: 10.1007/bf02215451] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
21
|
Booth S, Johns T, Lopez-Palacios CY. Factors influencing self-diagnosis and treatment of perceived helminthic infection in a rural Guatemalan community. Soc Sci Med 1993; 37:531-9. [PMID: 8211265 DOI: 10.1016/0277-9536(93)90288-f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Changes in the diagnosis and treatment of helminthic infection were examined during a longitudinal study in a rural community in Guatemala. Self-diagnosis was predominant, with an increase in perceived helminthic infection during an economic crisis within the community. Allium sativum L. and Chenopodium ambrosoides L. were used as anthelmintics, often in conjunction with commercial drugs. During the economic crisis the use of plants as treatment for perceived infection increased whereas use of commercial helminthic medicine decreased. Dietary modifications were observed during periods of perceived infection, but were not consistent in the food items modified or the nature of the modification. Within the community individuals exhibited considerable heterogenity in their approaches to treatment.
Collapse
Affiliation(s)
- S Booth
- School of Dietetics & Human Nutrition, McGill University, Montreal, Canada
| | | | | |
Collapse
|
22
|
Lunn PG, Northrop-Clewes CA. The impact of gastrointestinal parasites on protein-energy malnutrition in man. Proc Nutr Soc 1993; 52:101-11. [PMID: 8493254 DOI: 10.1079/pns19930042] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
There is no doubt that at high intensity of infection, intestinal parasites can cause severe illness and the death of their hosts. Even with the high prevalence of these infections, however, such severe cases are rare and the norm is for low to moderate numbers of parasites which cause few if any overt symptoms. Nevertheless, it has been argued that by causing subtle reductions in appetite, absorption, digestion and acute-phase status and increasing intestinal nutrient losses, these low-level but long-term infections could be responsible for the persistent, poor nutritional status of so many children in Third World communities. Although geographically, high parasite prevalence occurs in conjunction with high levels of protein-energy malnutrition, attempts to establish a cause and effect relationship have had very limited success with many investigators being unable to demonstrate any detrimental consequence of infection. The unimpressive results might be explained to some extent by the unusual features of helminth infections such as rapid reinfection, the overdisperse distribution pattern and the uncertainty of a host inflammatory response, but they also suggest that A. lumbricoides (on which most studies have concentrated) may be of little nutritional importance. It seems likely that the more invasive parasites, e.g. the hookworms, S. stercoralis, T. trichiura and perhaps G. lamblia may have a greater impact and clearly more studies are required here. Safe, cheap and effective anthelmintics are now available and, on the grounds of disease prevention, there is a case for their nationwide use. However, from the available evidence, it would be unwise to expect that such programmes would make a significant impact on the nutritional status of children in Third World communities.
Collapse
Affiliation(s)
- P G Lunn
- MRC Dunn Nutrition Centre, Cambridge
| | | |
Collapse
|
23
|
Solomons NW. Pathways to the impairment of human nutritional status by gastrointestinal pathogens. Parasitology 1993; 107 Suppl:S19-35. [PMID: 8115184 DOI: 10.1017/s003118200007548x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Gastrointestinal pathogens are of three varieties, those that can, and often do, take the life of the host, those that infect transiently and rarely are life-threatening, and those (parasites) that establish a relatively prolonged residence or colonization of the host's alimentary tract. In the case of the second form, if infections are recurrent, both catabolic effects during the episode and failure to digest foods and/or absorb nutrients results. Similarly, catabolic wastage through activation of the acute phase response, and interference with the host's acquisition of nutrients by maldigestion, malabsorption, intestinal losses and competition with the parasite burden can impair growth and nutrition with helminthic infections. Growth and nutrition with respect to all of the macronutrients and virtually all of the micronutrients have been documented to be adversely affected by gastrointestinal pathogens. For its burgeoning importance as a worldwide health problem, both with the HIV virus as a direct intestinal pathogen and with the opportunistic gut infections occurring in the immunocompromised host, AIDS represents the emerging context of the impairment of nutritional status by intestinal pathogens.
Collapse
Affiliation(s)
- N W Solomons
- Center for Studies of Sensory Impairment, Aging and Metabolism (CeSSIAM), Hospital de Ojos y Oidos, Guatemala City, Guatemala
| |
Collapse
|
24
|
Abstract
The present review will examine epidemiological perspectives and be confined mainly to the results of those field studies published since 1975 in order to provide concrete scientific evidence of the effect of ascariasis on childhood malnutrition, particularly on growth. The field studies were done in many developing countries from Africa, Asia and Latin America, using cross-sectional and intervention studies in which anthelmintics were employed, with different dosing frequency and follow-up periods ranging from 33 days to 2 years. In general, a better nutritional status in terms of growth, lactose tolerance, vitamins A and C, and albumin levels were observed among Ascaris-free or treated than among Ascaris-infected or untreated children even in cross-sectional or non-randomized studies. More importantly, the improvement in weight or height after chemotherapeutic treatment was found to be significant particularly in those randomized controlled studies with an initially high prevalence of ascariasis and malnutrition, a low prevalence of other intestinal parasites, repetitive and regular treatments of children with tetramisole, levamisole or pyrantel, within a period of 12 or 24 months. Reasons for failures to detect improved growth in some studies are provided. This review strongly indicates that A. lumbricoides infection definitely retards childhood growth.
Collapse
Affiliation(s)
- T Hlaing
- Department of Medical Research, Ministry of Health, Yangon, Myanmar
| |
Collapse
|
25
|
Hagel I, Lynch NR, Pérez M, Di Prisco MC, López R, Rojas E. Relationship between the degree of poverty and the IgE response to Ascaris infection in slum children. Trans R Soc Trop Med Hyg 1993; 87:16-8. [PMID: 8465384 DOI: 10.1016/0035-9203(93)90401-b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We examined a group of urban slum children in Caracas, Venezuela, and demonstrated the relationship that exists between poverty, conditions of hygiene and the prevalence of helminth infection. Concordant with the high prevalence of helminth infection in these children, the total serum levels of immunoglobulin E (IgE) and blood eosinophilia were elevated and were directly related to the degree of poverty and lack of sanitary facilities. However, in contrast, the reverse pattern was observed for the specific allergic response to these parasites. Thus, the immediate hypersensitivity skin test reactivity to Ascaris antigens, and the serum levels of specific anti-Ascaris IgE antibody, were lowest in the poorest children, who had the highest prevalence of helminth infection and the highest total IgE levels. As allergic-type reactions may participate in protective mechanisms against helminths, these results suggest that poverty and poor sanitary conditions may, by influencing the IgE response, compromise the resistance of such children to parasitic infections.
Collapse
Affiliation(s)
- I Hagel
- Institute of Biomedicine, Faculty of Medicine, Central University of Venezuela, Caracas
| | | | | | | | | | | |
Collapse
|
26
|
Sherman DR, Guinn B, Perdok MM, Goldberg DE. Components of sterol biosynthesis assembled on the oxygen-avid hemoglobin of Ascaris. Science 1992; 258:1930-2. [PMID: 1470914 DOI: 10.1126/science.1470914] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The parasitic nematode Ascaris infests a billion people worldwide. Much of its proliferative success is due to prodigious egg production, up to 10(6) sterol-replete eggs per day. Sterol synthesis requires molecular oxygen for squalene epoxidation, yet oxygen is scarce in the intestinal folds the worms inhabit. Ascaris has an oxygen-avid hemoglobin in the perienteric fluid that bathes its reproductive organs. Purified hemoglobin contained tightly bound squalene and functioned as an NADPH-dependent, ferrihemoprotein reductase. All components of the squalene epoxidation reaction--squalene, oxygen, NADPH, and NADPH-dependent reductase--are assembled on the hemoglobin. This molecule may thus function in sterol biosynthesis.
Collapse
Affiliation(s)
- D R Sherman
- Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | | | | | | |
Collapse
|
27
|
da Costa-Macedo LM, Rey L. Ascaris lumbricoides in neonate: evidence of congenital transmission of intestinal nematodes. Rev Inst Med Trop Sao Paulo 1990; 32:351-4. [PMID: 2135475 DOI: 10.1590/s0036-46651990000500007] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Clinical and epidemiological study of a forty-days-old infant with a diarrheic condition and insufficient development led to the coprological diagnosis of ascariasis and possible congenital infection. Specific treatment with levamisole, resulted in clinical and parasitological cure, in addition to gain of weight up to normal levels. Maternal parasitism had been diagnosed two months before labor and proved beyond doubt during the ensuing epidemiological inquiry.
Collapse
Affiliation(s)
- L M da Costa-Macedo
- Departamento de Parasitologia, Universidade do Estado, Rio de Janeiro, Brasil
| | | |
Collapse
|
28
|
Abstract
An overview of the problem of gastrointestinal (GI) helminthiases in Zimbabwe is given in terms of prevalence, distribution, clinical significance of individual parasites and their transmission patterns. Although data on these aspects are incomplete, the available information and the results of studies conducted elsewhere should assist in the planning and implementation of effective helminthiasis intervention strategies. Community-based integrated helminthiasis control measures that include mass chemotherapy, improved sanitation and health education are considered to be the most practical interventions and are being evaluated in Zimbabwe. This community-based approach is cost-effective, as most of the control measures are carried out on a self-help basis. Besides, local voluntary health committees provide consistent community-level surveillance to promote and motivate the population to join in the intervention measures that include improved sanitation and health education, aspects which have broader implications for improved health.
Collapse
|
29
|
Upatham ES, Viyanant V, Brockelman WY, Kurathong S, Lee P, Chindaphol U. Prevalence, incidence, intensity and associated morbidity of intestinal helminths in south Thailand. Int J Parasitol 1989; 19:217-28. [PMID: 2785975 DOI: 10.1016/0020-7519(89)90010-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Intensive surveys for Ascaris lumbricoides, Trichuris trichiura and hookworm were carried out in two villages in Phang Nga Province, southern Thailand, in order to measure prevalence, estimate incidence and determine the relation between intensity of infection and morbidity before and after chemotherapy. The study populations were a small upland village community (Nai Tone) and a grade school in a small coastal village (Boh Saen). About half of the Nai Tone villagers were given a broad spectrum antihelminthic (albendazole), and the Boh Saen students were all treated successively with three drugs: piperazine citrate to treat for Ascaris, pyrantel pamoate to treat for hookworm, and mebendazole to treat for Trichuris. Stool examinations were made using the quick Kato smear technique, questionnaires were administered concerning a variety of possible symptoms, and anthropometric and blood biochemical parameters were measured both before and after treatment. The prevalence of Ascaris was 31.0 and 22.6%, hookworm was 89.1 and 88.0% and Trichuris was 59.7 and 77.8% in the Nai Tone and Boh Saen study populations, respectively. Average intensity of Ascaris was highest in the 0-9 year age class (greater than 32,000 epg) in Nai Tone Village. Hookworm intensity of infection was higher in males than in females in all age classes, and in Nai Tone Village at least 25% of males and 20% of females had 8000 or more epg of faeces. Trichuris intensity of infection was highest between 5 and 10 years of age in both populations. The only signs or symptoms showing a significant (P less than 0.05) difference between high and low classes of intensity of infection and a significant improvement (P less than 0.01) after drug treatment, were headache and flatulance in the case of hookworm infection in Boh Saen School. The presence of multiple infections made testing of hypotheses concerning particular parasite species difficult.
Collapse
|
30
|
Slater AF, Keymer AE. The influence of protein deficiency on immunity to Heligmosomoides polygyrus (Nematoda) in mice. Parasite Immunol 1988; 10:507-22. [PMID: 3194148 DOI: 10.1111/j.1365-3024.1988.tb00239.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The influence of dietary protein on the efficiency with which mice could be immunized against infection with the nematode Heligomosomoides polygyrus was investigated. Immunization with irradiated larvae did not protect outbred mice fed synthetic diets containing 2% or 4% protein against a challenge infection, while animals fed a diet containing 8% protein were significantly resistant. In further experiments with high-responder NIH mice, protein malnutrition was again found to cause a significant depression in immunity. Immunization primed all mice for an intense production of antibody against larval worms in a challenge infection, and although a slightly higher titre of antibody was detected in the plasma of mice fed a 16% compared with a 2% protein diet it seemed unlikely that this was sufficient to account for the reduced resistance of the malnourished mice. The development of eosinophilia in the blood of immunized mice was significantly delayed in malnourished animals following challenge, and it is suggested that a reduction in the number of granulocytes attacking larval worms contributed to the low level of resistance observed in these animals. Protein malnutrition thus markedly suppresses the effectiveness of immunization of mice against an intestinal nematode, and it is suggested that this result may be of general significance with regard to the potential for widespread immunization of people against infections of this type.
Collapse
Affiliation(s)
- A F Slater
- Department of Zoology, University of Oxford
| | | |
Collapse
|
31
|
Affiliation(s)
- S N Wickramasinghe
- Department of Haematology, St Mary's Hospital Medical School, University of London, UK
| |
Collapse
|