Shigella, caused by the bacterium Shigella flexneri, is spread through water contaminated with faecal matter.

Almost two-thirds of worldwide shigellosis cases occur among children, 99 per cent of them in developing countries. The disease is endemic in Bangladesh.

Researchers from the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), located in Dhaka, have reported that breastfed babies withstand complications due to shigella infection better. These include seizures and, in later stages, changes in brain structure and function (known as ‘encephalopathy’), severe stunting and death.

Their findings were published in this month’s (May) issue of  The Pediatric Infectious Disease Journal.  

Infants whose mothers stopped breast-feeding early were 40 times more likely to develop encephalopathy, the researchers found.

"Cessation of breastfeeding in the neonatal [newborn] period is clearly an immediate and long-term risk factor for diarrhoeal disease,’’ Mohammed Zobayer Chisti, assistant researcher at ICDDR,B, told SciDev.Net.

Under a diarrhoeal disease surveillance programme, Chisti’s team studied 22,242 patients between 1997 and 2006, of whom 1,132 had shigella infection. They focused on 759 children, from less than a month old to 15 years of age, with shigella.

“Children who had proper breastfeeding were found to have more resistant power to fight shigella,’’ Chisti, who led the research, said.

The World Health Organization recommends that infants be ‘’exclusively breast-fed for the first six months of life to achieve optimal growth, development and health."

Apart from breast milk, children who did not receive vitamin A usually have lower retinol levels in serum as well as in the liver which may become further reduced in shigellosis. ‘’Vitamin A helps to build resistance against shigella in children’s bowels,’’ Chisti said.