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Asymptomatic giardiasis and growth in young children; a longitudinal study in Salvador, Brazil
M S Prado1, S Cairncross, A Strina
1Institute of Public Health, Universidade Federal da Bahia, Salvador, BA, Brazil.
Insights
Giardiasis, an infection from Giardia, can stunt young children's growth, even without diarrhea symptoms. This study suggests treating asymptomatic giardiasis in children is crucial for proper development.
Area of Science:
- Pediatrics
- Infectious Diseases
- Public Health
Background:
- Giardiasis is a common intestinal infection in developing countries.
- The impact of asymptomatic giardiasis on child growth remains debated.
- Early childhood growth is critical for long-term health outcomes.
Purpose of the Study:
- To evaluate the effect of Giardia infection on the anthropometric growth of young children.
- To determine if asymptomatic Giardia infections impede child growth.
- To inform treatment guidelines for childhood giardiasis.
Main Methods:
- Longitudinal study of 597 children (6-45 months) in Brazil over one year.
- Anthropometric measurements (height-for-age z-scores) taken thrice.
- Stool sample analysis for Giardia, with treatment for infected children.
Main Results:
- A significant reduction in height-for-age z-score gain (0.09) observed in the second 6-month interval for infected children.
- Infected children experienced a 0.5 cm shortfall in height gain compared to uninfected children.
- Growth deficits were more pronounced in asymptomatic children and correlated with untreated infection duration.
Conclusions:
- Giardia infection can impair child growth, likely through malabsorption, even in the absence of diarrhea.
- Findings challenge the practice of withholding treatment for asymptomatic giardiasis in young children.
- Early intervention for Giardia is recommended to prevent growth faltering in vulnerable populations.
Abstract:
This study sought to assess the effect of giardiasis on growth of young children. In Salvador, northeast Brazil, 597 children initially aged 6 to 45 months were followed for a year in 1998/9, measured anthropometrically thrice, every 6 months, and monitored for diarrhoea prevalence twice weekly. Stool samples were collected and examined during the second round of anthropometry, and infected children were treated 39 days later, on average (S.D. 20 days). For each 6-month interval, the gains in z-scores of infected and uninfected children were compared, after adjustment for potential confounding factors, including longitudinal prevalence of diarrhoea. No significant difference was found for the first interval but in the second, the gain in adjusted height-for-age z-score was 0.09 less in infected than uninfected children, equivalent to a difference in height gain of 0.5 cm. The shortfall in growth was greater in children who remained free of diarrhoea, and was significantly correlated with the proportion of the second interval during which the child had remained untreated. We conclude that Giardia can impede child growth even when asymptomatic, presumably through malabsorption. This finding challenges the view that young children found to have asymptomatic giardiasis in developing countries should not be treated.
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