Abstract
Background
Diarrhoea is a leading cause of mortality and morbidity among under-five year old children worldwide and the greatest burden of the disease is in sub-Saharan Africa. Nearly half of the approximately 9 million deaths annually in children aged under five years old are in Africa and 18% of them are due to diarrhoea. A comprehensive study was conducted to understand knowledge, attitudes and practices about diarrhoea in rural Africa, identify the pathogens responsible, assess possible risk factors and document early and medium term outcome after a diarrhoeal episode.
Method
A four year study was conducted in the Upper river region, The Gambia. Repeated health care utilization and attitude surveys (7 times in three years) among 1140 randomly selected caregivers of children aged under five years old were performed. A case control study of moderate to severe diarrhoea in under- five children was conducted. Cases presenting to health facilities and age, sex and area matched controls were recruited to detect aetiological agents from their stool samples. Risk factors were ascertained through interview and home visits. Both the case and control cohorts were followed after 60-90 days and 18-24 months to assess linear growth retardation after an acute episode of moderate to severe diarrhoea.
Results
Health Care and Attitudes Survey: The period prevalence and point prevalence of diarrhoea in the community were 23.3% and 7.7% respectively. 48.4% of the caregivers brought their children to a health centre for treatment. Only 10.3% of the caregivers thought dehydration was a matter of concern. Among the children who had diarrhoea, only 17% were given oral rehydration solution (ORS) at home as a part of management of diarrhoea, before attending a health centre. Caregivers of 43% of the children did not give any treatment, 72.5% of them gave less or withheld food during the episode of diarrhoea.
Case Control study: There was a decline in the facility based annual incidence rate of diarrhoea during the study period (13, 8 and 6 /100 child year of observation in 2008, 2009 and 2010 respectively). Bloody diarrhoea was observed in 24.1% of the case children; the rest had watery diarrhoea. Rotavirus (OR16.6, 95% CI: 9.8-28.2; p=<0.001), Shigella spp.(OR 4.7, 95% CI: 3.2-6.9; p=<0.001), Cryptosporidium spp. (OR 2.7, 95% CI; 1.9-3.8; p=<0.001), Enterotoxigenic Escherichia coli (ETEC) (OR 1.4, 95% CI: 1.1-1.7: p=0.009), and norovirus (OR 1.8, 95% CI: 1.3-2.3; p=<0.001) were the top five pathogens isolated from the children with acute moderate to severe diarrhoea (MSD). The overall pathogenicity indices of the top five pathogens in the children aged under five years old were 7.4, 3.8, 2.4, 2.2 and 2.1 for rotavirus, Shigella spp., norovirus (G2), Cryptosporidium spp. and ETEC producing heat stable (ST only) toxin respectively. Primary caregivers’ illiteracy (OR 3.1, 95% CI: 2.4-4.0; p=<0.001), having a donkey/horse/mule (OR 3.3, 95% CI: (2.5-4.3); p=<0.001), giving storage water (OR 5.2, 95% CI: (3.8-7.0); p<0.001) and untreated water (OR 8.4, 95% CI: (4.2-6.6); p<0.001), and absence of toilet facilities (OR 8.5, 95% CI:1.1-4.4; p=0.038), were risk factors for diarrhoea in the children. Hand washing before food handling, cooking and use of soap were found to be protective.
Follow-up on linear Growth Assessment: Children in Gambia are generally stunted and on average both the cases and controls had below zero for the reference length/height for age Z score (HAZ). HAZ further declined during the two follow-up periods. More children in the case cohort died over follow-up, especially in the first few months, and the catch up growth was slower in the case cohort than the control cohort at both follow-up assessments. This was not significant in the 0-11 month age group. However, the case cohort in the 12-23 months and 24-59 months age groups grew at significantly lower rates than the controls (p=0.001 and 0.004 respectively).
Conclusion
Diarrhoea remains a major problem in children aged under five years old in rural Gambia, there are clear opportunities for improved management in the community, the aetiologies of MSD have been clarified in this study and risk factors have been identified. Children with MSD are more likely to die in the months after an admission to hospital in The Gambia than community controls and their growth rates continue to track lower. A multipronged approach is necessary to face the challenge of controlling MSD in children. Now is the time to apply them in practice.