Breast feeding as a determinant of severity in shigellosis. Evidence for protection throughout the first three years of life in Bangladeshi children

Abstract

Little is known about the effect of breast feeding upon the severity of illness due to specific diarrheal pathogens. Using a systematically sampled and evaluated population of children aged less than 3 years, who attended a diarrheal disease hospital in Bangladesh, the authors performed a case-control study that assessed whether breast feeding reduces the severity of illness in shigellosis. From 540 children presenting with shigellosis between 1980-1982, they created a group of cases (n = 53) with severe illness and controls (n = 487) with non-severe illness. Overall, the odds ratio relating breast feeding to the severity of shigellosis (0.49, p = 0.01) suggested a substantial mitigating effect of breast feeding upon clinical severity. The high degree of protection against severe shigellosis was evident for breast-fed children up to 35 months of age, as well as for children at high risk for death because of severe malnutrition or measles. Because shigellosis continues to account for substantial morbidity and mortality in children in developing countries, the results support prolonged breast feeding in these settings.

PIP: The influence of breastfeeding on the severity of illness in shigellosis was assessed in a case-control study involving 540 children presenting with shigellosis to a Bangladesh diarrheal disease hospital in 1980-82. The 53 cases were children under 3 years of age with severe illness (i.e., rectal temperature above 102 F, severe neurologic manifestations, or severe dehydration), while the 487 age-matched controls had non-severe shigellosis. 42% of the cases compared with 59% of controls were breastfed, yielding an odds ratio of 0.49 (95% confidence interval, 0.28-0.86). This finding suggests that breastfeeding substantially shifts the spectrum of severity in Shigella infections from severe to non-severe illness. The high degree of protection against severe shigellosis was also seen in malnourished children and in children reporting a recent history of measles. The protective effect of breastfeeding persisted even when the analysis was corrected for the confounding effects of age, nutritional status, and earlier receipt of medication. These results are consistent with data from both developed and developing countries indicating that breastfeeding reduces the severity of illness in childhood diarrhea. In Bangladesh, about 1/3 of mothers breastfeed for 3 years. In other areas of the developing world, however, breastfeeding beyond infancy is relatively uncommon. Because shigellosis accounts for substantial morbidity and mortality in developing countries, prolonged breastfeeding is recommended