EVIDENCE-BASED ANSWER
While breastfeeding protects against all-cause diarrhea in infants1- 5 (strength of recommendation [SOR]: B, based on cohort studies and 1 randomized controlled trial), no evidence shows that breastfeeding confers specific protection against viral gastrointestinal infections. Several studies demonstrate that breastfeeding does not prevent acquisition of rotavirus but does decrease the severity of its course (SOR: B, based on cohort, case-control studies, and a systematic review lacking homogeneity).6-10
Evidence summary
Breastfeeding has been associated with decreased overall rates of diarrhea in infants in developed2-4 and developing1,5 countries. Many cases of gastroenteritis without a confirmed enteropathogen have viral causes. Rotavirus is a common viral pathogen in children aged <2 years, and much of the evidence about breastfeeding and viral gastroenteritis comes from studies about rotavirus infections.
Prospective cohort studies conducted in Canada6 and the United States7 showed no difference in the incidence of rotavirus gastroenteritis between infants up to 2 years of age who were breastfed and those who were not. Although differences were not found between either the incidence or the duration of rotavirus infections, these studies showed a significant decrease in the frequency of vomiting among breastfed infants.
A case-control study in Bangladesh suggests that breastfed infants have a higher incidence of rotavirus diarrhea, but selection of diarrhea patients as controls may have underestimated the protective effect.8 Although breastfeeding was not found to provide overall protection from developing rotavirus gastroenteritis, exclusive breastfeeding appeared to protect against severe rotavirus diarrhea for infants aged <2 years.
Another US study showed that risk for rotavirus infection did not differ for infants who were exclusively breastfed, partially breastfed, or exclusively formula-fed.10 However, the breastfed infants were more likely to have milder symptoms.
RECOMMENDATIONS FROM OTHERS
The American Academy of Family Physicians11 and the American Academy of Pediatrics12 recommend exclusive breastfeeding for a minimum of the first 6 months of life, and continuation of breastfeeding to supplement age-appropriate foods through the next 6 months. The World Health Organization13 recommends exclusive breastfeeding for the first 4 to 6 months of life, and continuation of breastfeeding for 2 years of age or beyond.
CLINICAL COMMENTARY
Another reason to encourage mothers to breastfeed
Mark Ellis, MD, MSPH
Cox Health Systems Family Practice Residency, Springfield, Mo
This review affirms that breast milk protects against diarrheal illness while questioning a specific effect in preventing rotavirus infections. Evidence that breast milk reduces severity of the world’s major cause of diarrheaassociated death, however, is sufficient basis to support breastfeeding.
I educate expectant mothers about breast milk’s disease-mitigating qualities and compliment breastfeeding mothers on giving this gift to their children. I discuss the impact of breastfeeding on incidence of otitis media, asthma, obesity, and all-cause diarrhea. I also counsel that breast milk may decrease severity of diarrhea because it is “easier on the digestive system” (lower osmolality) than formula.