Rotavirus

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Transmission Electron Micrograph of Rotavirus (CDC, Dr Erskine Palmer, 1978)

Contents

Introduction

Virus discovered in 1973 by Drs Ruth Bishop and Ian Holmes in Melbourne. Worldwide mortality is over 500,000 per annum without vaccination. Considerable morbidity exists in developed countries even if the chance of dying is about 1 in a million in these healthcare systems.Some outbreaks are due to poor food hygiene practices, including allowing contamination of irrigation water supplies[1].

Classification

Rotavirus is a double-stranded RNA virus,[2] in the Reoviridae virus family.

Classifcation of rotaviruses is based on the genotypes producing two outer shell proteins:

  • P genotypes (23) produce the VP4 protein
  • G genotypes (15) produce the VP7 protein

Commonest strains are:

  • G1P[8]
  • G2P[4]
  • G3P[8]
  • G4P[8]
  • G9P[8]

Clinical

Rotavirus is a common cause of gastroenteritis in children.

Pediatric presentation

Presents as diarrhoea predominant gastroenteritis with fever [3]

  • Intensive diarrhoea
  • Fever (97%) - only 81% temperature > 38°C
  • Vomiting

Investigations

  • Stool electron microscopy
  • Rotavirus EIA on stool

Treatment

Medical

  • Rehydration and general supportive care

Prevention

Immunisation

The two outer shell proteins VP4 and VP7 stimulate human protective immunity.

In the USA rotavirus vaccines have been considered, and thus far discarded.[2]

A vaccine (Rotashield®) seemed to cause intussusception in a small proportion of those given it. In developing countries, where the mortality and morbidity from rotavirus infection is much greater, the vaccine would have saved more lives than it took from intussusception; but to give a vaccine that could kill, especially when it was not used in the USA, was considered unacceptable.[2]

Several new vaccines are now close to licensure or recently licensed.[2][4] These include Rotarix ® (RIX4414) a G1P[8] genotype based vaccine that might offer 79% protection for two seasons and RotaTeq® a G1P[8]-G4P[8] pentavalent ressortant vaccine. It seems possible that immunisation against P[8]] also protects against P[4] genotypes and certainly against various common P[8] genotypes other than G1P[8]. Although the mortality and morbidity rates for rotavirus infection are not high in developing countries such as the USA and the UK, so many people are ill with it that, even with relatively low morbidity rates, the cost of treating cases (hospitalisation etc.) - especially if non-health-sector costs such as those incurred by parents taking time off work to look after sick children - probably exceed the cost of vaccination, and it is not unlikely that a rotavirus vaccine will become part of the routine childhood vaccination schedule in developing countries, in due course. Indeed RIX4414 produced in European infants a 71% all-cause reduction in hospital admissions from gastroenteritis[5] and in predominantly Latin American infants a 39% reduction[6].

In February 2006 TotaTeq (Merc) was licensed in the USA and early results [7] seem positive. Whether the vaccine will be added to routine schedules is not yet decided.

In March 2010 Rotarix® use was suspended by the FDA while the significance of contamination by DNA from porcine circovirus type 1 was investigated although the EMEA reported that no action is necessary as there was no public health threat.

Notification

  • As for gastroenteritis

ICD code

A08

External links

CDC (Atlanta) factsheet on rotavirus. Accessed 16 February 2009 http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-rotavirus.pdf

References

  1. Brassard J, Gagné MJ, Généreux M, Côté C. Detection of human food-borne and zoonotic viruses on irrigated, field-grown strawberries. Applied and environmental microbiology. 2012 May; 78(10):3763-6.(Link to article – subscription may be required.)
  2. a b c d Pankhania B. The evolution of an effective rotavirus vaccine. Vaccines in practice 2008;2(1):1-4 (provisional citation - in press)
  3. Narkeviciute I, Tamusauskaite I. Peculiarities of norovirus and rotavirus infections in hospitalised young children. Journal of pediatric gastroenterology and nutrition. 2008 Mar; 46(3):289-92.(Link to article – subscription may be required.)
  4. Glass et al. Rotavirus vaccines: current prospects and future challenges. Lancet 2006;368:323-32. DOI:10.1016/S0140-6736(06)68815-6 or (for possibly only for subscribers) full text at Lancet website
  5. Vesikari T, Karvonen A, Prymula R et al. Efficacy of human rotavirus vaccine against rotavirus gastroenteritis during the first 2 years of life in European infants: randomised, double-blind controlled study Lancet 2007; 370:1757-1763
  6. Ruiz-Palacios GM, Pérez-Schael I, Velázquez FR, Abate H, Breuer T, Clemens SC, Cheuvart B, Espinoza F, Gillard P, Innis BL, Cervantes Y, Linhares AC, López P, Macías-Parra M, Ortega-Barría E, Richardson V, Rivera-Medina DM, Rivera L, Salinas B, Pavía-Ruz N, Salmerón J, Rüttimann R, Tinoco JC, Rubio P, Nuñez E, Guerrero ML, Yarzábal JP, Damaso S, Tornieporth N, Sáez-Llorens X, Vergara RF, Vesikari T, Bouckenooghe A, Clemens R, De Vos B, O'Ryan M. Safety and efficacy of an attenuated vaccine against severe rotavirus gastroenteritis. The New England journal of medicine. 2006 Jan 5; 354(1):11-22.(Link to article – subscription may be required.)
  7. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm57e625a1.htm accessed 26 February 2009
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