Risk Factors for Constant, Severe Trachoma among Preschool Children in Kongwa, Tanzania

Abstract

Trachoma, an ocular infection caused by Chlamydia trachomatis, is the second leading cause of blindness worldwide. The blinding sequelae, which occur in middle age, are felt to be the result of numerous or lengthy episodes of severe inflammatory trachoma in childhood. Risk factors for constant, severe trachoma were identified in a group of children enrolled in a longitudinal study in Kongwa, Tanzania, where villages were randomized in a clinical trial of mass treatment and a behavior modification campaign. In 1989, each of 1,417 randomly selected children had photographs taken of an upper eyelid for determination of their trachoma status. The photographs were graded by a reader who was masked as to the village and date of each photograph. Risk factor data on the family's socioeconomic status, distance to water, and hygiene practices were obtained at baseline. Follow-up examinations occurred 2, 6, and 12 months from baseline. Data from all four time points were available for 82% of the children enrolled. Overall, 10% of the children had constant, severe trachoma, defined as severe trachoma at three or four examinations. The odds ratio for severe trachoma was 1.9 for female children (95% confidence interval 1.3-2.7). Familial cattle ownership and having one or more siblings with trachoma at baseline were also significantly related to the odds of having severe trachoma. Children with a sustainably clean face had lower odds (odds ratio = 0.4, 95% confidence interval 0.3-0.7). A subgroup of 10% of children in these hyperendemic communities always seemed to have severe trachoma, despite enrollment in a mass treatment campaign. Improved face-washing plus antibiotic treatment may decrease the likelihood that these children will be at risk for blinding complications in adulthood.

Trachoma and ocular Chlamydia trachomatis rates in children in trachoma–endemic communities enrolled for at least three years in the Tanzania National Trachoma Control Programme

“…Using quantitative PCR in Tanzania, Elimination of Blinding Trachoma by the year we have shown 90% of infection within the 2020 (GET 2020) has endorsed a multifaceted community resides in pre-school children (West trachoma control program for countries endemic et al, 1991, 1996Solomon et al, 2003; West et for trachoma (WHA, 2003). There is sound public al., 2005).…”

“…the pool of active inflammatory trachoma Because of its absence in developed countries, resides in the young children who may have trachoma was largely forgotten as a public persistent signs of active trachoma as result of health issue until a new antibiotic donation repeated or persistent infections (West et al, program coupled with renewed focus by the 1991; West et al, 1996). In hyperendemic areas, World Health Organization (WHO) rekindled active disease prevalence in pre-school children interest in eradicating blinding trachoma.…”

Prevalence of trachoma in the adult Chinese population. The Beijing Eye Study

“…[1][2][3][4] Since recent population based studies on the prevalence of trachoma and its associations with demographic and ocular risk factors are scarce for the population of mainland China, 5,6 it was the purpose of the present study to assess the frequency of trachoma and its associations in Chinese adults living in Greater Beijing.…”

Trachoma as cause of blindness: literature review

“…In hyperendemic areas, a subgroup of children, about 8-10%, seem to have constant infection and persistent severe inflammation (26)(27)(28) The incidence of scarring is nearly five times higher in these children than in children with active trachoma, but without severe inflammation [29]. In addition, scar formation can continue to develop in people living in areas that are not endemic [30], suggesting that the tissue damaged by infection with chlamydia can undergo progressive healing after injury by other bacterial pathogens [31].…”