Child health and acute respiratory infections in Ethiopia epidemiology for prevention and control

Abstract: This thesis is based on studies in Butajira district in the south central part of Ethiopia and one study in the Ethio-Swedish Children's Hospital in Addis Ababa. The Butajira project has a continuous demographic surveillance system, established in 1987 in a sample of 10 communities with a total baseline population of about 30,000. The project includes the development and evaluation of a system for continuous registration of vital events and provides a baseline population and sampling frame for health related research activities. The thesis used different study designs within the surveillance system. A carriership study was undertaken to determine the potential bacterial respiratory pathogens among under-five children. A clinical study was done to investigate aetiological agents among young infants (below 3 months) with pneumonia, sepsis and meningitis in a hospital setting. Interview studies were carried out on mothers' perceptions of illness and practices in the care of children with acute respiratory infections. Within the surveillance system, patterns of under-five mortality were analysed. A nested case-referent design was applied to assess public health and behavioural determinants of mortality. A cohort study was performed among under-fives in three communities to estimate the magnitude of illness burden, particularly from ARI, as well as to assess determinants of ARI morbidity.Among 1126 under-five children, 85% were found to harbour H. influenzae, 83% M. catarrhalis and 90% S. pneumoniae in the nasopharynx. The hospital-based study isolated S. pneumoniae, Streptococcus group A, Salmonella group B, E. coli and H. influenzae in the age group below 3 months. The study of mothers' perceptions and practices, showed that mothers do know the symptoms of measles and whooping cough, while they do not recognize pneumonia as an illness entity and are not aware of fast breathing as an important sign of pneumonia.The mortality studies showed a high infant and under-five mortality rate. ARI was responsible for one fifth of the under-five mortality and almost one third of the infant mortality rate. Cause of death in the case-referent study was determined using a validated verbal autopsy method. Breast-feeding and supplementary feeding were demonstrated to be strongly protective when controlling for parental and environmental determinants of mortality.A one year prospective home surveillance study showed that illness was reported in 5.8% of 1,216 person-years. ARI contributed half of this illness load and was particularly associated with parental factors. Among sanitation factors, the absence of piped water was an important determinant of morbidity. Among housing factors, the type of roof and lighting source for the house, and among parental factors, illiteracy of either parents and having a farmer as a father, were found to be independently associated with increased morbidity. Among health and behavioural factors, preterm delivery and lack of immunization were associated with increased morbidity.The results of the studies of this thesis have been utilized to design an intervention case management package. The intervention study and evaluation of its impact is now on-going.