Diarrhoeal diseases in low- and middle-income countries : trends, management and control

Abstract

Background: Diarrhoeal diseases constitute a major disease burden on children in low- and middle-income countries (LMC), with an estimated 2 million 0-4 years old dying annually due to diarrhoea. Dehydration is the main cause of these deaths. An oral remedy based on glucose and sodium to treat dehydration was developed in the 1960s. Significant efforts have since been made to promote the use of Oral Rehydration Therapy (ORT). Adoption of ORT has lead to significant child mortality reductions. Meanwhile, little change in diarrhoea morbidity in low- and middle-income countries has been reported.

Main aim: The main aim of this thesis is to make a contribution to improved child health in low- and middleincome countries by enhancing knowledge on diarrhoeal diseases control, especially on case management and morbidity reductions.

Methods: The first two studies were conducted in Northeastern (NE) Brazil, a region of 9 states and a population of 51 million. The first study evaluated diarrhoea case management through a household cluster survey of 6 524 children 0-4 years old. The second study used a health facility survey to assess quality of diarrhoea child care in 78 randomly selected primary care facilities. The third study was methodological and analysed paired results from two types of household surveys in eight countries to assess their validity. In the fourth study, diarrhoea management in LMC from 1986 to 2003 was analysed for four variables from up to 107 cross-sectional surveys. In the fifth study three indicators of diarrhoea morbidity in the state of Ceará in NE Brazil were assessed for trends 1998-2005 and the association between determinants and morbidity studied.

Results: The household survey in NE Brazil showed that 982 children (15%) had suffered from diarrhoea during 15 days preceding the interview. ORT was given to 24%. 95% of the caretakers knew about rehydration solutions, but only 18% prepared them correctly, the most common error being the use of insufficient water. The health facility survey in NE Brazil showed that case management based on ORT was established in health services but also pointed to deficiencies in management. Utensils for administration of ORT were available in only half of the facilities. Health workers showed deficiencies in history taking, examination and communication to parents. Still, in 84% of 75 observed child visits ORT was prescribed. In the study on results from comparable surveys, around half of the survey pairs showed a statistically significant variation, rejecting a hypothesis of no difference. This pointed to the possibility of systematic errors in data collection in household surveys. The study of data on case management from household surveys showed limited progress in diarrhoea management in LMC 1986–2003. Achievements in ORT use were far below global targets set at the beginning of the 1990s. An estimated 307 million children did not get ORT and 356 million did not get more to drink during diarrhoea at the beginning of the 21st century. The study in Ceará, Brazil provided some evidence that diarrhoea morbidity went down slightly 1998-2005. The decline was strongest for diarrhoea admissions. Few determinants of morbidity could be associated with the three indicators of diarrhoea morbidity.

Conclusions: This thesis has pointed to achievements and problems in diarrhoeal diseases control from 1986 to 2005. ORT became well known in that period. At the same time, unsatisfactory adoption and application of ORT in the late 1980s documented from Brazil persisted in most LMC over the 1990s. Also, diarrhoea case management was found to meet logistical and managerial problems in primary health services, contributing to inadequate utilization of ORT. Much more research is needed on how to improve diarrhoea case management in LMC.

Findings from Ceará, Brazil in the thesis support other studies that have shown limited decline in diarrhoea morbidity in LMC. More research is needed on the interaction between morbidity, case management and mortality for proper understanding of priority setting in diarrhoea control. Efforts to reduce diarrhoea morbidity should be further strengthened, especially among the poorest. The thesis has also documented the need for further research on how to strengthen the methodology of household surveys, a key instrument in impact evaluation.

The thesis highlights that there is little time for complacency in strengthening diarrhoeal diseases control. Around 300 million children in the LMC appear not to get Oral Rehydration Therapy, the treatment that is essential for prevention of death from diarrhoea. This fact should lead international organisations, donors and national governments to again give high priority to diarrhoeal diseases, especially in low-income countries where diarrhoea is a daily life-threatening condition to many children.