Bovine reassortant rotaviruses

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 It was licensed in the United States in 1998 and subsequently withdrawn from the market due to an association with intussusception.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. 

Various oral rotavirus vaccines (live attenuated rotavirus vaccines, including rhesus rotavirus and bovine rotavirus strains serotype 1 bovine-human rotavirus reassortant vaccine and both rhesus rotavirus monovalent and tetravalent reassortant vaccines) have been evaluated in clinical trials (SEDA-21, 292). 

Eichelberger MC, Sperber E, Wagner M, Hoshino Y, Dudas R, Hodgins V, Marron J, Nehring P, Casey R, Burns R, Karron R, Clements-Mann ML, Kapikian AZ. Clinical evaluation of a single oral dose of human-bovine (UK) reassortant rotavirus vaccines Wa x UK (PlA[8j, G6) and Wax(DS-lxUK) (PlA[8j, G2). J Med Virol 2002 66(3) 407-16. 

The first vaccine (RotaShield) to prevent rotavirus infection was licensed for use in the United States in 1998, but it was withdrawn from the market after 1.5 million doses were administered owing to an increased rate of idiopathic intussusception. A number of rotavirus vaccines are under development, but the one that shows early promise is the rotavirus oral vaccine (Rotateq, Merck). This is a reassortant pentavalent vaccine with a backbone of bovine rotavirus and surface proteins of virus strains representing G types (G1-G4) and PI A. The preliminary results from the trial of 1946 healthy infants (aged 2 to 8 months) showed a level of protection of approximately 75%. ... 

---