Browsing by Author "Wong, Michael S."

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
  • Thumbnail Image
    Item
    School performance nutritional status and trichuriasis in Jamaican school children
    (1994) Simeon, Donald T.; Callender, J.; Wong, Michael S.; Grantham-McGregor, Sally M.; Ramdath, D. D.
    The study examined the relationship between varying intensities of Trichuris trichiura infections and school achievement, attendance, and nutritional status in 616 schoolchildren. A total of 409 children with Trichuris infection of intensities greater than 1200 eggs per gram of stool (epg) were first identified, then for every 2 infected children in a class, an uninfected child was selected. After controlling for socio-economic status, gender, age, school and the presence of Ascaris infections, the infected children had higher reading and arithmetic scores than children with infections of more than 4000 epg and were taller than those with intensities greater than 2000 epg. However, there were no significant differences in spelling, school attendance and body mass index. Although a treatment trial is needed to determine causation, these results indicate that moderate levels of infection are associated with poor school achievement and growth.
  • Thumbnail Image
    Item
    Treatment of Trichuris trichiura infections improves growth, spelling scores and school attendance in some children
    (1995) Simeon, Donald T.; Grantham-McGregor, Sally M.; Callender, Joy E.; Wong, Michael S.
    The effects of treating Trichuris trichiura infections were investigated in 407 Jamaican children age 6-12 years. The children were randomly assigned to receive treatment (albendazole) or a placebo. The outcome variables included growth; tests of reading, spelling and arithmetic; and school attendance. After six months of treatment, there was no significant main effect on any of the outcomes. However, there were significant treatment-by-infection intensity interactions with spelling and body mass index and a significant treatment-by-stunting interaction with school attendance. In spelling the children with heavy infections showed improvements with treatment that approached significance, whereas those with lower intensities did not. However, the children with lower infection intensities had increased body mass index with treatment, although there was no difference in children with heavy infections. In school attendance, the stunted children improved with treatment, whereas there was no difference in the non-stunted children. These findings suggest that in the sample of Jamaican children examined, the treatment of T. trichiura was more likely to benefit school performance in children of poor nutritional status and those with heavy infections, and to improve weight gain in children with lighter infection intensities.
  • Thumbnail Image
    Item
    Trichuris trichiura infection and cognition in children: Results of a randomized clinical trial
    (1995) Wong, Michael S.; Grantham-McGregor, Sally M.; Simeon, Donald T.
    The effects of mild to moderate infections of Trichuris trichiura on cognitive functions were investigated in Jamaican children aged 7-10 years. In all 189 infected children and 100 uninfected classmates we studied. The infected children were randomly assigned to receive treatment (albendazole) or a placebo. All children were given cognitive tests at the time of enrolment and 14 weeks later. These included verbal fluency (generation of ideas), digit span (working memory), number choice (speed of processing of visual stimuli), visual search (sustained attention), and French vocabulary test (paired-associate learning). At baseline, the infected children had lower scores than the uninfected in fluency, search, and French. Treatment effects were examined among infected children and there was no significant treatment by weight-for-age interaction in fluency. The children with low weight-for-age improved with treatment while there was no improvement with treatment among the older children. It was concluded that treatment of children with mild to moderate T. trichiura infections using albendazole produces little benefit on cognition if they are adequately nourished; however, under-nourished children are more likely to benefit.