Lack of an adverse effect of Giardia intestinalis infection on the health of Peruvian children.
ABSTRACT Giardia intestinalis is a common gastrointestinal protozoan worldwide, but its effects on childhood growth in developing countries are not clearly understood. The authors aimed to describe its effects on child growth. They followed 220 Peruvian children daily for diarrhea, weekly for stool samples, and monthly for anthropometry. The authors modeled the effect of nutritional status on the risk of Giardia infection and the risk of diarrhea attributable to Giardia using negative binomial regression. They modeled the effects of Giardia infection on growth using linear regression, with 85% of children becoming infected with Giardia and 87% of these becoming reinfected. In multivariable analysis, the risk of Giardia infection did not vary with weight for age (relative risk = 1.00, 95% confidence interval: 0.89, 1.12) or height for age (relative risk = 0.92, 95% confidence interval: 0.82, 1.04). Giardiasis did not affect growth at 1 or 2 months following the first infection at any age interval. The longitudinal prevalence of Giardia between 6 and 24 months of age was not associated with height gain in that interval (p = 0.981). Giardia was not associated with an increased risk of diarrhea at any age interval. Study results question the importance of Giardia as a childhood pathogen in developing countries where giardiasis is hyperendemic.
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ABSTRACT: SUMMARY Giardiasis is a gastrointestinal disease that affects humans and other animals caused by parasitic protists of the genus Giardia. Giardia intestinalis (Syn. Giardia lamblia; Giardia duodenalis) infections can cause acute or chronic diarrhoea, dehydration, abdominal discomfort and weight loss. Metronidazole is the most widely used drug for treating giardiasis. Although effective, metronidazol has undesirable secondary effects. Plants used in traditional medicine as antidiarrhoeals or antiparasitics may represent alternative sources for new compounds to treat giardiasis. Heterotheca inuloides Cass. (Asteraceae/Compositae) plant is widely used in Mexican traditional medicine. The following secondary metabolites were isolated from H. inuloides flowers: 7-hydroxy-3,4-dihydrocadalene (1), 7-hydroxycadalene (2), 3,7-dihydroxy-3(4H)-isocadalen-4-one (3), 1R,4R-hydroxy-1,2,3,4-tetrahydrocadalen-15-oic acid (4), quercetin (5), quercetin-3,7,3'-trimethyl ether (6), quercetin-3,7,3',4'-tetramethyl ether (7) and eriodictyol-7,4'-dimethyl ether (8). The activity of these compounds against Giardia intestinalis trophozoites was assessed in vitro as was the activity of the semisynthetic compounds 7-acetoxy-3,4-dihydrocadalene (9), 7-benzoxy-3,4-dihydrocadalene (10), 7-acetoxycadalene (11), 7-benzoxycadalene (12), quercetin pentaacetate (13) and 7-hydroxycalamenene (14). Among these, 7-hydroxy-3,4-dihydrocadalene (1) and 7-hydroxycalamenene (14) were the most active, whereas the remaining compounds showed moderate or no activity. The G. intestinalis trophozoites exposed to compound 1 showed marked changes in cellular architecture along with ultrastructural disorganization. The aim of this study was to evaluate the giardicidal activity of selected H. inuloides metabolites and some semisynthetic derivatives using an in vitro experimental model of giardiasis.Parasitology 11/2014; DOI:10.1017/S0031182014001619 · 2.35 Impact Factor
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ABSTRACT: The short-term association between diarrhea and weight is well-accepted, but the long-term association between diarrhea and growth is less clear. Using data from 7 cohort studies (Peru, 1985-1987; Peru, 1989-1991; Peru, 1995-1998; Brazil, 1989-1998; Guinea-Bissau, 1987-1990; Guinea-Bissau, 1996-1997; and Bangladesh, 1993-1996), we evaluated the lagged relationship between diarrhea and growth in the first 2 years of life. Our analysis included 1,007 children with 597,638 child-days of diarrhea surveillance and 15,629 anthropometric measurements. We calculated the associations between varying diarrhea burdens during lagged 30-day periods and length at 24 months of age. The cumulative association between the average diarrhea burden and length at age 24 months was -0.38 cm (95% confidence interval: -0.59, -0.17). Diarrhea during the 30 days prior to anthropometric measurement was consistently associated with lower weight at most ages, but there was little indication of a short-term association with length. Diarrhea was associated with a small but measurable decrease in linear growth over the long term. These findings support a focus on prevention of diarrhea as part of an overall public health strategy for improving child health and nutrition; however, more research is needed to explore catch-up growth and potential confounders.American journal of epidemiology 08/2013; DOI:10.1093/aje/kwt094 · 4.98 Impact Factor