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.
Rotavirus Vaccines
There are two vaccines available against rotavirus. Both are given orally (by mouth). RotaTeq® contains five different but related strains of rotavirus, and in clinical trials cut the number of exposed children who developed rotavirus gastroenteritis by 75%, and the number of hospital admissions by 96%. RotaRix® contains one strain of rotavirus but can protect against several other strains as well. These vaccine is given orally (by mouth). RotaTeq® is given 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 8 months; the recommended schedule is to give the vaccine at ages 2 months, 4 months, and 6 months. RotaRix® is given in 2 doses with at least 4 weeks between doses, and is usually given at ages 2 and 4 months. Like RotaTeq®, Rotarix® should not be given after age 8 months. The vaccines contain 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®
and RotaRix®
included extra measures to look at the vaccine's safety. There have been
no added incidence of intussusception, or other bad side effects, that
were strongly associated with either vaccine, but the
CDC,
the FDA, and the vaccine manufacturers
are watching very closely for any further problems in children who
receive either vaccine. As always, you should talk to your child's doctor
about the risks and benefits of the rotavirus vaccine.
An Extraneous Virus in Rotarix®
On March 22, 2010, the US Food and Drug Administration recommended that physicians and others who give vaccines suspend, at leat for now, use of Rotarix®, after a research team found DNA from a non-rotavirus virus called a circovirus. The circovirus was found by new laboratory methods, has apparently been in Rotarix since the vaccine's early clinical trials, and has never been shown to cause illness in people or animals.
The circovirus DNA discovered in Rotarix are fragments of the circovirus DNA, and it is still not clear if intact and infection-causing virus particles are in the vaccine. There have been no reported infections of circovirus in people, which makes it very unlikely that there are intact virus particles in Rotarix. The FDA recommended that use of Rotarix be suspended until more was known about the circovirus DNA and its presence in Rotarix. On May 14, 2010, the FDA lifted the suspension, and Rotarix is again available for use. Bear in mind that circovirus has not been shown to cause an illness, that no safety problems have been found in infants or other who have taken the vaccine, and that the risk of serious illness or death from rotavirus gastroenteritis is much higher than any problems seen so far with Rotateq. As always, you should talk to your child's doctor about the risks and benefits of the rotavirus vaccine.