The incidence and clinical presentation of infantile rotavirus diarrhoea in Sierra Leone.

OBJECTIVES An effective vaccine is needed to protect against severe rotavirus disease, an important cause of gastroenteritis. Since there are no data on the incidence and antigenic diversity of rotavirus infection in Sierra Leone, we studied its epidemiology to enable an effective vaccine strategy to be designed. METHODS Children between the ages of 3 and 30 months presenting with gastroenteritis to the Ola During Children's Hospital in Freetown, Sierra Leone, were enrolled. Stool specimens were tested in South Africa using polyacrylamide gel electrophoresis to confirm rotavirus infection. RESULTS Over a 5-month period 143 children presenting with gastroenteritis were recruited. Stool samples obtained from 128 study subjects were tested for the presence of rotavirus; 45% were aged between 3 and 9 months (mean age 10.85 months), and 48 stool samples (37.5%) tested positive for rotavirus. The incidence of rotavirus infection was 20% higher in boys than in girls, a gender difference confirmed elsewhere in West Africa. The prevalence of rotavirus-positive stools peaked in August, coinciding with the rainy season. About 90% of the rotavirus-positive patients had severe diarrhoea, as opposed to only about two-thirds of the patients whose diarrhoea was not caused by rotavirus; this difference was statistically significant. CONCLUSIONS There is a high incidence of rotavirus infection in Sierra Leone, with rotavirus causing 37.5% of the gastroenteritis in this study. Patients with rotavirus gastroenteritis almost all had severe diarrhoea. The high incidence of rotavirus infection and the severity of the disease presentation make the institution of a rotavirus vaccine programme in Sierra Leone imperative.