Today I thought I’d write a little bit about the recent complications being discovered with the Rotavirus vaccine.  Below find information regarding the virus itself and the recently noted contamination of the vaccine.

On March 22, 2010, the FDA reported that an independent research team had found Rotarix (one of the two main rotavirus vaccines) to be contaminated with porcine circovirus-1 (PCV-1,) a virus that affects pigs.  PCV-1 has not been known to cause clinical complications in pigs, and the use of Rotarix was only temporarily suspended.

PCV-2, however, is a lethal, immunosuppressive disease that causes damage to the lungs, brain, reproductive system, and causes death in baby pigs.  On May 7, 2010, it was announced that RotaTeq (the other rotavirus vaccine) was found to be contaminated with both viruses, PCV-1 AND PCV-2.  Despite the contamination, the FDA has not called for a suspension of use of this vaccine….perhaps parents should.

Rotavirus background:

Rotavirus is the primary cause of severe diarrhea in children.  This virus is trasmitted via the fecal/oral route, and is highly contagious.  In the United States, there are five major strains that cause disease, but in developing countries there are many more.  Symptoms include watery diarrhea, vomiting, fever, dry or cool skin, lethargy, decreased urination, decreased tear production, abdominal pain, and extreme thirst.

Based on the above symptom list, it is pretty obvious that most of us have suffered a bout with rotavirus as children, probably called “the stomach flu.”  In fact, the CDC estimates that nearly every US child has been infected with rotavirus by age 3.  Due to the development of antibodies, subsequent infections cause less severe, if any, symptoms.  Most children over age 5 suffer few severe infections.

Rotavirus requires no special treatment.  Rest and adequate hydration are typically the only treatments.  The most severe complication is dehydration.

RotaShield, introduced in 1998 by Wyeth, was the first vaccine for rotavirus.  This vaccine was pulled from the market in the fall of 1999 due to an increased incidence of intussusception–a complication in which the intestine folds in on itself, causing obstruction.  In pre-licensure trials, cases of intussusception were not shown to be greater in the vaccinated group than placebo.  However, with more widespread use, it was estimated that 1 in 5000 to 9500 vaccinated infants were affected.

Currently, there are two main vaccines for rotavirus.  The following descriptions can be found at the National Vaccine Information Center website (www.nvic.org):

Rotarix, by GlaxoSmithKline:

• Rotarix is a genetically engineered vaccine made of live attenuated human rotaviruses. Other ingredients include: amino acids, dextran, sorbitol, sucrose, and Dulbecco’s Modified Eagle Medium (DMEM). DMEM contains sodium chloride, potassium chloride, magnesium sulfate, ferric (III) nitrate, sodium phosphate, sodium pyruvate, D-glucose, concentrated vitamin solution, L-cystine, L-tyrosine, amino acids solution, L-glutamine, calcium chloride, sodium hydrogenocarbonate, and phenol red. The liquid diluent contains calcium carbonate, sterile water, and xanthan.

RotaTeq, by Merck:

• RotaTeq is a genetically engineered vaccine made of   live, attenuated human-bovine hybridized reassortant rotaviruses. Other ingredients include sucrose, sodium citrate, sodium phosphate monobasic monohydrate, sodium hydroxide, polysorbate 80, cell culture media, and trace amounts of fetal bovine serum. It does not contain preservatives. (NVIC)

Pigs may be cute, but pig viruses in human vaccines are not.