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Abstract
Rotaviruses are the single most important etiologic agents of severe diarrheal illness of infants and young children worldwide with group A rotaviruses being the most important cause of severe acute diarrhea in young children throughout the world.
Rotavirus is classified as a genus in the family Reoviridae. The rotavirus genus currently has five species (Rotavirus A to Rotavirus E), with two possible additional species (Rotavirus F and Rotavirus G). The intact virion is about 60 - 80 nm in diameter and is characterized by a distinctive triple-layered capsid. The inner capsid encompasses the core containing the virus genome. The genome consists of 11 segments of double¬stranded RNA (dsRNA), which encodes six structural and six nonstructural proteins. The members of each species share a common group antigen located in the middle layer of the mature viral particle (VP6).
Rotavirus replication occurs in the cytoplasm of mature epithelial cells lining the tips of the villi of the small intestine. Infection alters the function of the small intestinal epithelium, resulting in diarrhea. The diarrhea is generally considered to be malabsorptive, secondary to enterocyte destruction; in addition, a secretory component of diarrhea was also suggested based on elevated levels of secreted prostaglandin E2 (PGE2) in the infected gut.
Recent data presented at the 6th International Rotavirus Symposium in Mexico City, indicate that the annual number of deaths due to rotavirus infection may be as high as 608,000 deaths per year, 82% of which occur in developing countries; (39 % of 1.56 million deaths of all diarrheal cases worldwide). Globally, rotaviruses account for approximately 138 million cases of infantile gastroenteritis each year, 25 million clinic visits and hospitalizations in children under 5 years of age. An estimated 1,205 children die from rotavirus disease every day. By the age of 5 years, almost all children will experience at least one episode of rotavirus gastroenteritis, one in 5 children will require a clinic visit, one in 65 children will require hospitalization and approximately 1 child in 293 will die.
In the present study, serological detection of rotavirus was done by using ELISA technique, on 247 stool specimens collected from children with acute gastroenteritis, who attended the outpatient clinic in EL-Chatby Hospital in Alexandria, over an 18 months period from October 2005 to April 2007. A questionnaire was completed for each patient including the name, age, sex, breast or formula feeding, time of sample collection, time of onset of diarrhea, average number of motions per day, relevant clinical and environmental data.
Rotavirus was detected in 33.6% of the collected samples; no specific age group or sex predilection was observed. It was presented with a marked seasonal peak during autumn and winter (61.4%). Rotavirus was found to be infecting most commonly under weight children (46.9 %) resulting into fluid loss and severe dehydration (80%). Rotavirus acute gastroenteritis was found to be associated with fever (38.8%), vomiting (39.9%), watery stools, and long duration of diarrheal episodes lasting from one up to six days. Bloody stools (16.7%) and flu-like symptoms (31.3%) didn’t seem to be significantly