Rotaviruses

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). 

Fig. 1. Preparative separation of the components of the concentrated culture fluid on the PVT-porous glass column. (/) fraction of purified rotaviruses, (2, 3) other components of the culture fluid [32]...

Fig. 2a-c. Electron micrographs of the chromatographic fractions (a) concentrated culture fluid containing rotaviruses ( x 30000), (b) purified rotaviruses (fraction 1, Fig. 1, x 50000), (c) other components of culture fluid (fraction 3, Fig. 1, x 30000) [32]... 

Fig. 5. Preparative separation of the components of concentrated culture fluid on the porous glass chemically modified by the copolymer of N-VP and N-HEAA. 30 ml of concentrated culture fluid was applied to the column (2.3x90 cm) equilibrated with 0.01 mol/1 phosphate buffer, pH 7.4 and eluted with this buffer at flow rate 300 ml/h. (1) — fraction of purified rotavirus, (2, 3) — other components of the culture fluid [51]...

Viruses are small infectious agents composed of a nucleic acid genome (DNA or RNA) encased by structural proteins and in some cases a lipid envelope. They are the causative agents of a number of human infectious diseases, the most important for public health today being acquired immunodeficiency syndrome (AIDS), hepatitis, influenza, measles, and vituses causing diarrhoea (e.g., rotavirus). In addition, certain viruses contribute to the development of cancer. Antiviral drugs inhibit viral replication by specifically targeting viral enzymes or functions and are used to treat specific virus-associated diseases. 

Acute gastroenteritis Norovlrus and Sapovims, Rotavirus, Astrovirus some... 

Reoviruses Rotavirus An inner core is surrounded by tv/o concentric icosahedral shells producing particles 70nm in diameter A very common cause of gastroenteritis in infants. It is spread through poor water supplies and when standards of general hygiene are low. In developing countries it is responsible for about a million deaths each year... 

Susceptibility of viruses to antimicrobial agents can depend on whether the viruses possess a lipid envelope. Non-lipid viruses are frequently more resistant to disinfectants and it is also likely that such viruses cannot be readily categorized with respect to their sensitivities to antimicrobial agents. These viruses are responsible for many nosocomial infections, e.g. rotaviruses, picornaviruses and adenoviruses (see Chapter 3), and it may be necessary to select an antiseptic or disinfectant to suit specific circumstances. Certain viruses, such as Ebola and Marburg which cause haemorrhagic fevers, are highly infectious and their safe destruction by disinfectants is of paramount importance. 

Plaque assays, at present, apply to only a very limited number of viruses, e.g. poliovirus, herpes virus, human rotavirus. The principle ofthese assays is as follows test virus is dried on to coverslips which are immersed in various concentrations oftest disinfectant... 

Bon, F., Fascia, P., Dauvergne, M., Tenenbaum, D., Planson, H., Petion, A. M., Pothier, P., and Kohli, E. (1999). Prevalence of group A rotavirus, human calicivirus, astrovirus, and adenovirus type 40 and 41 infections among children with acute gastroenteritis in Dijon, France. /. Clin. Microbiol. 37,3055-3058. 

Pang, X. L., Joensuu, J., and Vesikari, T. (1999). Human calicivirus-associated sporadic gastroenteritis in Firmish children less than two years of age followed prospectively during a rotavirus vaccine trial. Pediatr. Infect. Dis. J. 18,420 26. 

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. 

Viruses are the most common cause of diarrheal illness in the world. A live, oral vaccine is licensed and recommended for use in infants for the prevention of rotavirus infection. 

Viruses are the most common cause of diarrheal illness in the world, resulting in about 450,000 and 160,000 hospitalizations for adults and children, respectively, and over 4000 deaths.40,41 A number of viruses may cause gastroenteritis, including rotaviruses, noroviruses, astroviruses, enteric adenoviruses, and coronoviruses (Table 73-4). This chapter will focus on rotaviruses. 

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... 

I The cornerstone of rotavirus treatment is supportive care and rehydration with ORT or intravenous fluids if necessary. Antimotility and antisecretory agents should not be used... 

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 first rotavirus vaccine was a tetravalent rhesus rotavirus strain. It was licensed in the United States in 1998 and subsequently withdrawn from the market due to an association with intussusception. A pentavalent human-bovine reassortant rotavirus vaccine was approved by the FDA in February 2006. The exact mechanism by which the vaccine produces an immune response is unknown however, this live virus vaccine replicates in the small intestines and induces immunity. 

The rotavirus vaccine is a three-dose series that is orally administered. The first dose is given to infants between 6 and 12 weeks of age with subsequent doses administered 4 to 10 weeks apart. 

Jaimes MC, Rojas OL, Kunkel EJ, et al. Maturation and trafficking markers on rotavirus-specific B cells during acute infection and convalescence in children. J Virol 2004 78 10967-10976. 

Zeng, C.Q., Wentz, M.J., Cohen, J. et al. (1996) Characterization and replicase activity of double-layered and single-layered rotavirus-like particles expressed from baculovirus recombinants. Journal of Virology, 70 (5), 2736-2742. 

Nayak B, Panda AK, Ray P et al (2009) Formulation, characterization and evaluation of rotavirus encapsulated PLA and PLGA particles for oral vaccination. J Microencapsul 26 154-165... 

Potato virus X second sgp, CP fusion, CP fusion with FMDV 2A element, IRES elements GFP, rotavirus, scFv, 25, 26, 62, 63... 

Rotavirus VP6 protein Potato tuber Anti-GAR antibodies detected. Immunogenic -in mice when delivered parenterally. 112... 

Rotavirus VP6 protein Tomato callus No immunogenicity assays. - 32-34... 

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