Rotavirus diarrhea

Rotavirus and infectious diarrhea Rotavirus is the most common cause of severe diarrhea in infants and young children worldwide. This virus, which is mainly transmitted through fecal-oral contamination, infects and damages mature enterocytes in the small intestine, and causes watery diarrhea, fever, and vomiting (Parashar et al. 2003). 

Rotavirus. Rotavims causes infant diarrhea, a disease which has major socio-economic impact. In developing countries it is the major cause of death in infants worldwide, causing up to 870,000 deaths per year. In the United States, diarrhea is stiU a primary cause of physician visits and hospitalization, although the mortaUty rate is relatively low. Studies have estimated a substantial cost benefit for a vaccination program in the United States (67—69). Two membrane proteins (VP4 and VP7) of the vims have been identified as protective epitopes and most vaccine development programs are based on these two proteins as antigens. Both Hve attenuated vaccines and subunit vaccines are being developed (68). 

There are many possible causes of acute diarrhea, but infection is the most common cause. Infectious diarrhea occurs because of food and water contamination via the fecal-oral route. Viruses are the cause in a large proportion of cases. Likely viral suspects include Rotavirus, Norwalk, and adenovirus. Patients usually exhibit sudden low-grade fever, vomiting, and watery stools. 

The mechanism of diarrhea has not been clearly elucidated, but theories include a reduction in the absorptive surface along with impaired absorption owing to cellular damage, enterotoxigenic effects of a rotavirus protein, and stimulation of the enteric nervous system.43... 

Rotavirus 6 mo-2 yr Winter 3-8 days Fecal-oral, water, food Diarrhea, vomiting, fever, abdominal pain... 

Rotavirus is the most common cause of diarrhea worldwide. Most children will become infected by the age of 5 years. In the United States, rotavirus is responsible for approximately 50,000 hospitalizations for severe diarrhea and dehydration, and 20 to 40 deaths annually. Most hospitalizations occur in children less than 3 years of age. 

The highest frequency of rotavirus-associated diarrhea appears in children less than 5 years of age. The incubation period is typically 1 to 3 days. 

Rotavirus — the most common cause of severe diarrhea in infanfs, with approximately 125 million cases worldwide per year and 600,000 deaths — vaccines have been linked with intussusceptions (a problem with the intestine in which one portion of the bowel slides into the next) at a rate of between 1 in 5000 and 1 in 11,000 infants. The only rotavirus vaccine approved in the United States, RotaShield (Wyeth-Ayerst), was withdrawn from market on October 22, 1999, about 1 year after licensure. 

A good example of the recent and future evolution of viral vaccines and their concomitant issues of technology, complexity and competition, is the rotavirus vaccine. This is of great relevance for the prevention of diarrhea, which is often deadly in developing countries (half a million deaths per year) and has high hospitalization costs in rich countries. After successive failures of monovalent vaccines, multivalent vaccines based on the reshuffling of rotavirus strains comprising the attenuation properties of animal strains with the external capsid of human serotypes were developed. 

Fischer TK, Bresee JS, Glass RI (2004), Rotavirus vaccines and the prevention of hospital acquired diarrhea in children, Vaccine 22( Suppl 1) S49—54. 

Sarker, S.A., Casswall, T.H., Mahalanabis, D., Alam, N.H., Albert, N.J., Briissow, H., Fuchs, G.J., and Hammarstrom, L. 1998. Successful treatment of rotavirus diarrhea in children with immunoglobulin from immunised bovine colostrum. Pediatr. Infect. Dis. J. 17, 1149-1154. 

Schaller, J.P., Saif, L.J., Cordle, C.T., Candler, E. Jr, Winship, T.R., and Smith, K.L. 1992. Prevention of human rotavirus-induced diarrhea in gnotobiotic piglets using bovine antibody. J. Infect. Dis. 165, 623-630. 

When substantial carbohydrate maldigestion occurs in infants, it can lead to diarrhea. This is most often seen when the infant has experienced some other insult that has damaged the small intestine enterocytes, producing a secondary hypolactasia.This is more so when the infant has a rotavirus infection, and rotavirus is the most important cause of gastroenteritis in infancy. Rotavirus infects only mature enterocytes,... 

Infants are especially vulnerable to dehydration and electrolyte loss due to diarrhea. In a recent year, three million children worldwide, most from Third World countries, died from diarrhea due to various causes. Diarrhea in infants may be due to cholera, parasites, gastritis, a type of E. coli bacteria, rotavirus, and other viruses. In the United States, fifty-five thousand children were hospitalized with rotavirus in 1997, and forty of them died. 

Viral and bacterial organisms account for most episodes of infectious diarrhea. Common causative bacterial organisms include Shigella, Salmonella, Campylobacter, Staphylococcus, and Escherichia coli. Food-borne bacterial infection is amajor concern, as several major food poisoning episodes have occurred that were traced to poor sanitary conditions in meat-processing plants. Acute viral infections are attributed mostly to the Norwalk and rotavirus groups. 

Rotavirus is the most important cause of diarrhea worldwide, and 1 million people die annually from the infection. In the United States, approximately 3.5 million cases of diarrhea, 500,000 physician visits, 50,000 hospitalizations, and 20 deaths occur each year in children younger than 5 years of age. In developing countries, almost all children younger than 5 years of age are infected with rotaviruses. The... 

Rotaviruses are double-stranded wheel-shaped RNA viruses. These strains cause diarrhea by infecting the enterocyts of the villi in the small intestine. Changes to the villi include shortening of villus height, crypt hyperplasia, and mononuclear cell infiltration of the lamina propria. Diarrhea results from decreased absorption across intestinal mucosal surface. ... 

The rotavirus incubation period is less than 48 hours. Clinical manifestations of rotavirus infections vary from asymptomatic (which is common in adults) to severe nausea, vomiting, and diarrhea with dehydration. The first infection tends to be the most severe. Symptoms are... 

Laboratory findings reflect the degree of vomiting, diarrhea, or both. Transient rises in liver enzymes may be seen in 60% of children hospitalized for rotavirus diarrhea. The WBC count is usually normal. Stools rarely contain blood or leukocytes. Rotavirus detection in stool samples is possible with an enzyme immunoassay and a latex agglutination assay, both of which are available commercially. 

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