Introduction

Diarrhoeal disease is one of the five leading causes of morbidity and mortality among children aged between zero and five years. Global estimates show that deaths due to diarrhoea have declined from 4.6 million in the 1980s (Snyder and Merson, 1982) to 3.3 million in the 1990s (Bern et al., 1992) and to 2.5 million in 2000 (Kosek et al., 2003). Much of the improvement is possibly due to improvement in health treatment and management and increased use of Oral Rehydration Therapy (ORT) in the developing countries (WHO, 2004). However, morbidity has not shown a parallel decline despite the improvement in infrastructural facilities in developing countries. This is possibly because of limited changes in behavioural factors such as hand washing and low levels of awareness. The incidence of diarrhoea attacks among the children per year was at 3.2 episodes per child in 2000 in developing countries (Kosek et al., 2003).

In Bangladesh diarrhoeal diseases cotinue to play a significant role among the causes of death among children below five years of age according to the Interim Poverty Reduction Strategy Paper (PRSP) published by the Government of Bangladesh in 2002. These children are malnourished and therefore vulnerable to diarrhoea related deaths. Around 125,000 children under five die each year from diarrhoea, i.e. 342 children per day as per the PRSP repot.

As Bangladesh is a riverine country, floods are a common natural hazard.