RV

Rotavirus Vaccine

Content reviewed against published CDC, AAP, WHO guidelines

Editorial policy

Last reviewed:

Key takeaways

  • Prevents: Rotavirus gastroenteritis, Severe diarrhea and dehydration in infants
  • Schedule: 3 doses starting at 2 months
  • Effectiveness: Both vaccines are 85-98% effective against severe rotavirus disease and 74-87% effective against any rotavirus disease.
  • Most common side effect: Mild fussiness or irritability

How it works

The rotavirus vaccine is a live, attenuated (weakened) oral vaccine. It contains weakened strains of rotavirus that replicate in the small intestine without causing significant disease. This stimulates the immune system to produce antibodies and immune memory, so when the child encounters wild-type rotavirus, the immune system can quickly mount a defense and prevent severe illness.

Recommended schedule

DoseAge
Dose 12 months
Dose 24 months
Dose 36 months (RotaTeq only; Rotarix is 2-dose series)

Side effects

Common (mild, resolve in 1-2 days)

  • Mild fussiness or irritability
  • Mild, temporary diarrhea
  • Vomiting (less than 7%)
  • Decreased appetite for 1-2 days
  • Mild fever

Serious (very rare)

  • Intussusception (bowel obstruction) — approximately 1 in 20,000 to 1 in 100,000 vaccinated infants, most within 7 days of first dose
  • Severe allergic reaction — extremely rare

Who should NOT get this vaccine

  • History of intussusception
  • Severe combined immunodeficiency (SCID)
  • Severe allergic reaction to a previous dose of rotavirus vaccine
  • Age older than 15 weeks 0 days for the first dose (to minimize intussusception risk)
  • Uncorrected congenital malformation of the gastrointestinal tract

Effectiveness

Both vaccines are 85-98% effective against severe rotavirus disease and 74-87% effective against any rotavirus disease. Since introduction, rotavirus hospitalizations in the US have declined by approximately 85-95%.

Available brands

RotaTeq

Merck (pentavalent, 3 doses)

Rotarix

GlaxoSmithKline (monovalent, 2 doses)

Myths vs. facts

Myth: “My baby doesn't need this because rotavirus isn't that serious

Fact: Before the vaccine, rotavirus caused approximately 55,000-70,000 hospitalizations, 200,000 ER visits, and 20-60 deaths annually in the US alone. Worldwide it killed over 500,000 children per year. It is the leading cause of severe diarrhea in young children.

Myth: “The oral vaccine is less effective than injected vaccines

Fact: Oral administration is actually ideal for rotavirus because it mimics natural infection through the gut, creating strong intestinal immunity right where the virus attacks. Clinical trials show 85-98% effectiveness against severe disease.

Myth: “The vaccine causes intussusception

Fact: While there is a very small increased risk (approximately 1-1.5 additional cases per 100,000 infants), the benefit far outweighs the risk. Without the vaccine, the risk of rotavirus hospitalization is about 1 in 67 — far higher than the intussusception risk.

Frequently asked questions

Why is the rotavirus vaccine given by mouth instead of injection?
Rotavirus infects through the gut, so oral delivery stimulates strong intestinal immunity directly where it is needed. This approach mimics natural infection and provides more effective protection against the virus.
What if my baby spits up the vaccine?
If the baby spits up or vomits within minutes of receiving the dose, a replacement dose may be given during the same visit. Studies show the vaccine is still effective even if a small amount is spit up.
Can a vaccinated baby spread the virus to others?
Vaccinated babies can shed weakened vaccine virus in their stool for about 1-2 weeks. This is generally not dangerous to healthy household contacts but immunocompromised individuals should practice good hand hygiene around recently vaccinated infants.
Why is there an age limit for starting the vaccine?
The first dose must be given before 15 weeks of age because the small risk of intussusception appears to be higher in older infants. The series must be completed by 8 months of age.

Sources

All content follows our editorial policy and is reviewed against published clinical guidelines.

2,705 evidence-based guides6 authoritative medical sources

Bottom line

The Rotavirus Vaccine (RV) is safe, well-studied, and recommended by the CDC, AAP, and WHO. Talk to your pediatrician if you have questions about timing or your child's specific health needs.

Choosing to vaccinate your child is one of the most important things you can do to protect their health. If you have concerns, your pediatrician is always happy to talk through them with you.