Rotavirus, which causes severe gastroenteritis, doesn’t get the same degree of attention that others viruses like measles or chickenpox get, but it can be a troublesome infection especially for young children. The CDC lists a number of daunting statistics for children under 5. Rotavirus causes: 70,000 annual hospitalizations, more than 400,000 doctors visits and 200,000 emergency room visits. Furthermore, it is virtually certain that ALL children will have contracted a rotavirus infection before the age of 5. Worldwide, especially in areas where rehydration is not readily available, the story is much worse. The WHO estimates that the infection kills half a million kids a year.
However, with the advent of two vaccines, RotaTeq (co-invented by ACSH friend Dr. Paul Offit) in 2006 and Rotarix in 2008, these statistics have been rendered obsolete, this according to new data. A study funded by the CDC and published in JAMA this week, compared rotavirus and acute gastroenteritis hospitalizations numbers in children under 5 between two periods: pre-vaccine (2000-2006) with post-vaccine (2008-2012).
Most of the time, the source of acute gastroenteritis is not specifically identified because the treatment, fluid and electrolyte replacement, is the same regardless of the identity of the contagion. However, some estimates suggest that almost half of all acute gastroenteritis cases in children under 5 are caused by the rotavirus. This makes looking at the rates in acute gastroenteritis cases over these time periods a good metric of the effectiveness of the vaccine.
By analyzing patient discharge data across 26 states, the researchers identified 1.2 million cases of acute gastroenteritis, one-sixth of which had specifically identified rotavirus as the causative agent. The researchers found that in the pre-vaccine period, rotavirus cases had a frequency of 16 in 10,000 patients, however in the post-vaccine era the incidence dropped to just 1 in 10,000 patients. For acute gastroenteritis cases the incidence went from 76 cases per 10,000 children in the pre-vaccine era to 34 cases per 10,000 children in post-vaccine era.
The evidence is clear: the vaccines are working.
The RotaTeq vaccine is given in 3 doses bimonthly starting at 2 months of age, while the Rotarix vaccine is given twice, once at 2 months and again at 4 months. Both vaccines are given orally instead of being injected. The CDC highly recommends children receive the entire course of either vaccine before reaching 8 months of age.