Rotavirus is a common cause of diarrhea and gastroenteritis in children. Rotaviruses (there are 9 different, but related, types) can be passed from person to person by contact with infected stools, and tends to run rampant in places like day-care centers with a lot of susceptible kids, as well as going through families -- and adults who are not immune can get rotavirus, and sometimes need IV fluids themselves. It usually takes 1 to 3 days after exposure to become infected.
Although symptoms vary from person to person, most commonly a person infected with rotavirus begins with frequent vomiting -- sometimes as often as every 5-10 minutes, or every time she tries to eat or drink something (even water) -- and a fever (typically up to 102-103 F). Diarrhea begins about a day later, and can also be as often as every 5-10 minutes. The diarrhea stools are usually watery and can smell foul, but blood is usually not seen in rotavirus diarrhea. The vomiting usually subsides before the diarrhea; once the vomiting resolves, some patients can manage to drink enough fluids to keep themselves hydrated despite all the fluid they are losing in their stools. However, severe vomiting and diarrhea can dehydrate you to the point where you need IV fluids, and once a patient is on IV fluids I usually keep them on the IV until they are drinking well and can keep up with stool losses. During the "season" it's not uncommon to have many children hospitalized with dehydration; I once admitted 8 children with rotavirus gastroenteritis and dehydration to the hospital in two days.
Rotaviruses are found around the world. They are responsible for about 1 in 20 cases of diarrhea in children, but up to 8 in 20 cases of severely dehydrated children. It is the most common cause of diarrhea in children less than 2 years old seen by medical personnel, and is a major cause of death (from dehydration) in the Third World.
There is little that can be done to treat a rotavirus infection directly,
since it is a viral infection. Fatal dehydration is rare when IV fluids
are available, but oral
rehydration formulas can be given to many patients to help keep them
hydrated until they can fight off the infection themselves. Breast feeding
won't prevent rotavirus infections completely, but breast-fed children often
have milder cases of rotavirus than bottle-fed children.
The New Rotavirus Vaccine
RotaTeq®, a new oral vaccine against rotavirus, was approved on February 3, 2006 by the US Food and Drug Administration (FDA). (The link is to the FDA press release announcing approval.) In clinical trials, the vaccine cut the number of exposed children who developed rotavirus gastroenteritis by 75%, and the number of hospital admissions by 96%. The vaccine is given orally (by mouth) in 3 doses with 4-10 weeks between doses. The first dose has to be given between 6 and 12 weeks after birth, and the last dose by age 32 weeks (testing of the vaccine for children outside these ranges has not yet been completed); the recommended schedule is to give the vaccine at ages 2 months, 4 months, and 6 months. The vaccine contains weakened live virus particles, like the measles-mumps-rubella and chickenpox vaccines; at present it is not recomended for infants with immune-system problems including proven HIV infection or who were born to mothers with HIV.
A vaccine against the four most common types of rotavirus was available in the United States in mid-1999. However, the US Centers for Disease Control and Prevention (CDC) and the Advisory Committee on Immunization Practices (which includes representatives of the CDC and the American Academy of Pediatrics) stopped recommending the old vaccine after some infants who received it developed intussusception of the bowel within 1-3 weeks after receiving a dose of the vaccine.
The clinical trials of RotaTeq® included extra measures to look at the vaccine's safety. There was no added incidence of intussusception, or other bad side effects, reported initially with RotaTeq®. However, on February 13, 2007, FDA announced that about 28 cases of intussussception had been reported in infants who had received RotaTeq®. These cases occurred up to 10-1/2 weeks after receiving a dose of vaccine (so far there is no clear association with which dose -- #1, #2, or #3 -- was given). About half of the reported cases occurred within 3 weeks of a dose of the vaccine. So far, the number of babies who developed intussusception after receiving RotaTeq® is not higher than the number of babies who would develop intussusception even if they were not vaccinated.
Another issue that has arisen with RotaTeq® is a possible association with Kawasaki disease, an inflammatory disease seen in children. We don't know for sure what causes Kawasaki disease, although we suspect that it is an infection of some sort. Typically, Kawasaki disease appears with fever accompanied by conjunctivitis, sore throat, swollen glands in the neck, red lips, and/or swollen or peeling hands and feet. Not all of these signs show up in every patient with Kawasaki disease. The big problem with Kawasaki disease is that patients often have inflammation of the coronary arteries, leading to aneurysms (bulges in the walls) of those arteries. These aneurysms can burst, or throw clots which block blood flow, usually with disastrous results. However, Kawasaki disease is readily treated if diagnosed in a timely manner.
The FDA and the CDC have reported that 5 cases of Kawasaki disease have been seen in children who had received RotaTeq®. As with intussusception, the number of babies who developed Kawasaki disease after receiving RotaTeq® is not higher than the number of babies who would develop Kawasaki disease even if they were not vaccinated.
Frankly, I would give my own child RotaTeq® right now even with this information -- although I would certainly watch for symptoms and signs of intussusception or Kawasaki disease. Some babies develop these diseases anyway, whether or not they receive the vaccine; babies have had intussusception or Kawasaki disease much longer than they have been given vaccines in general, much less rotavirus vaccines. The CDC, the FDA, and RotaTeq®'s manufacturer are watching very closely for any further problems in children who receive RotaTeq®. As always, you should talk to your child's doctor about the risks and benefits of the rotavirus vaccine.