Contrasting roles of rivers and wells as sources of drinking water on attack and fatality rates in a hepatitis E epidemic in Somalia

• Published in: The American journal of tropical medicine and hygiene Vol. 51; no. 4; p. 466
• Main Authors: Bile, K, Isse, A, Mohamud, O, Allebeck, P, Nilsson, L, Norder, H, Mushahwar, I K, Magnius, L O
• Format: Journal Article
• Language: English
• Published: United States 01-10-1994
• Subjects: Acute Disease; Adolescent; Adult; Age Factors; Child; Child, Preschool; Disease Outbreaks; Female; Fresh Water; Hepatitis Antibodies - blood; Hepatitis E - epidemiology; Hepatitis E - mortality; Hepatitis E virus - immunology; Humans; Incidence; Infant; Male; Middle Aged; Pregnancy; Pregnancy Complications, Infectious - epidemiology; Pregnancy Complications, Infectious - mortality; Rain; Seasons; Sex Factors; Somalia - epidemiology; Water Supply; Somalia
• ISSN: 0002-9637
• DOI: 10.4269/ajtmh.1994.51.466

In early 1988, an increased incidence of acute hepatitis was observed in villages along the Shebeli River in the Lower Shebeli region of Somalia. This was followed by a large epidemic that lasted until late 1989. In a survey of 142 villages with a population of 245,312 individuals, 11,413 icteric cases were recorded, of which 346 died, corresponding to an attack rate and a case fatality rate of 4.6% and 3.0%, respectively. The etiologic role of hepatitis E virus (HEV) in this epidemic was proven by demonstrating anti-HEV in 128 of 145 sampled cases as a sign of recent infection with HEV. In three villages, where a special study protocol was implemented, the attack rate was found to increase significantly with age from 5% in the group 1-4 years of age to 13% in the group 5-15 years of age and to 20% for persons older than 15 years of age. Among cases 20-39 years of age, the female-to-male ratio was 1.5:1, which was a significant predominance of females. As in other hepatitis E outbreaks, there was a high fatality rate in pregnant females, estimated to be 13.8%. The epidemic peaked with the rise in the level of the river during rainfall, suggesting that the disease was waterborne. The attack rate was higher (6.0%) in villages supplied with river water, while fewer cases were recorded in those relying on wells or ponds for their water supply, 1.7% and 1.2%, respectively.