ABSTRACT
Since their discovery in 1973 (1), rotaviruses have frequently been identified as the most common diarrheal disease requiring treatment or hospitalization in children under 5 years of age (2–4). Worldwide, rotaviruses account for approximately 9% of the 1.5 billion diarrheal episodes (2) and 20–40% of the 4.6 million diarrhea-associated deaths in children under 5 years of age (5). The overall picture, however, is quite different between the developed and developing parts of the world. In the developed world, 70% of all children under the age of 5 years are expected to develop rotavirus-based gastroenteritis, with only 1001 in 8 requiring further care from a physician: death occurs only rarely (6–8). In the developing world, the prevalence of rotaviruses in the etiology of gastroenteritis is between 20% and 46% of all cases, but the absolute number of cases recorded, as well as the death toll, which stands at around 10% of the infections in children under 5 years of age (9), ensures an immense socioeconomic impact of this disease. Development of efficient rotavirus vaccines is therefore a priority. While early attempts had limited success, more recent approaches offer some promise for application in the developing world (10). However, widespread vaccine trials will be necessary before the true efficacy of these candidate vaccines can be evaluated.
