In the 1999, the US Advisory Committee on Immunisation Practices removed a vaccine called RotaShield (Wyeth Laboratories) was removed from the market as it was found to be associated with a rare type of bowel obstruction where the bowel folds in on itself, called intussusception.
Currenty the oral (swallowed) vaccines that are approved for use are RotaTeq™ (Merck) and Rotarix™ (GlaxoSmithKline).
RotaTeq™ is an oral, three-dose, live vaccine containing a strain of rotavirus isolated from a cow combined with proteins from five other strains of human rotavirus, namely G1, G2, G3, G4 and P1 which are the common human rotavirus strains responsible for more than 90 percent of rotavirus infections worldwide. The vaccine can be administered to infants between the ages of 6 to 32 weeks in three oral doses four to 10 weeks apart.
According to the information provided by The Children’s Hospital of Philadelphia, the introduction of the cow rotavirus (which will not cause infection in children) and the human rotavirus proteins (which will produce protective antibodies but will not cause an infection), will help infants build immunity. This vaccine contains no thimerosal, which is a preservative that is 50% ethyl mercury by weight.
Rotarix is an oral, two-dose, live attenuated vaccine, a weaker form of the virus that has been developed from a single human rotavirus strain. According to GlaxoSmithKline, “The vaccine works by stimulating the body to mimic the immune response to natural rotavirus infection, which protects against the subsequent development of moderate to severe rotavirus disease.” The vaccine can be administered to infants about two and three months of age (the first dose can be given as early as 6 weeks and the second dose before 6 months of age), in two oral doses one to two months apart.
Two studies published in The New England Journal of Medicine reported that both RotaTeq and Rotarix were effective in protecting infants against severe rotavirus gastroenteritis, significantly reduced the rate of severe gastroenteritis from any cause and were not associated with an increased risk of intussusception. The 2 clinical trials involved some 130,000 children from Belgium, Finland, Germany, Italy, Latin America (e.g. Brazil, Mexico, Venezuela), Sweden, Taiwan and the US.
Some children may develop a low-grade fever (99 to 100.9 degrees or 37.3 to 38.3 Celcius), which is a common side effect.
Source : Centers for Disease Control and Prevention (CDC); “Safety and Efficacy of an Attenuated Vaccine against Severe Rotavirus Gastroenteritis” Guillermo M. Ruiz-Palacios, et al. New England Medical Journal (2006) 354:11-22; Safety and Efficacy of a Pentavalent Human-Bovine (WC3) Reassortant Rotavirus Vaccine” Timo Vesikari, et al. New England Medical Journal (2006) 354:23-33; The Children’s Hospital of Philadelphia, Vaccine Education Center
[This is just for information ONLY! Mercury in vaccines is linked to autism.]
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Chapter: Rotavirus ::
20 June 2007
