Probiotics Will Not Prevent Infants From Getting Sick

Child care is an important aspect of many households. It is estimated that 3 of 5 children younger than 5 years in the United States participates in a child care arragement.¹ It is also known that these children are more likely than their counterparts to become ill, with a 2- to 3-fold increased risk of contracting respiratory tract and gastrointestinal (GI) tract illnesses. These infections can be a significant emotional and financial stress on families.

Preventive strategies have been investigated in prior studies, which have supported the use of probiotics in preschool-aged children. Two particular strains, Bifidobacterium animalis subsp lactis (BB-12) and Lactobacillus rhamnosus (LGG), have been shown to decrease the incidence or duration of respiratory infections, GI tract infections, and overall missed days from school/child care. Less is known about the impact of probiotics at the enrollment of child care. With this in mind, Laursen and colleagues² sought to examine the impact of probiotic administration (both BB-12 and LGG) on child care absence due to illness in Danish infants.

The ProbiComp study was a randomized, double-blind, placebo-controlled study in which caregivers administered either a placebo or a combination of BB-12 and LGG for a 6-month period. The children included were full-term singletons between 8 and 14 months of age at the initiation of the study who were in good health. The study personnel and parents were both blinded to the product received (placebo vs probiotics). Daily and weekly web-based questionnaires were sent to caretakers to assess child care absences, illness symptoms, and doctor visits.

The median absence from child care was 11 days. No difference was found between the probiotics and placebo groups through an intention-to-treat analysis. There were also no differences identified between the number of physician visits, diagnosed upper or lower respiratory tract infections, antibiotics, occurrence and duration of diarrhea, days of fever, or caregivers’ absence from work. It is worth noting that median study compliance was 97% without a difference noted between the 2 groups. Parents completed 99% of daily questionnaires and at least 98% of weekly questionnaires.

Several studies suggest a protective effect of probiotics for preschool-aged children. There are several interpretations as to why the results of this study were different. Almost half of the participants (47.4%) were still breastfeeding at the time of this study. Due to the protective components of breast milk, it is possible that there was not a significant difference between the 2 groups. Also, 33.5% of the formulas used were supplemented with probiotics, and 57.2% were supplemented with prebiotics; it is unclear whether this played a role in the results, as well.

This study suggests that giving an infant a combination of these particular strains of probiotics on a daily basis at the time of enrollment will not reduce days of illness, respiratory or GI tract symptoms, or days missed from child care. More studies must be done to determine the role of probiotics in illness prevention at this age, and pediatricians should encourage good hand hygiene, routine vaccinations, and breastfeeding (as mothers are able) for now as the protective factors for infants in child care.

References:

1. Laughlin L. Who’s minding the kids? Child care arrangements: Spring 2011 [published online April 2013]. United States Consus Bureau. https://www.census.gov/prod/2013pubs/p70-135.pdf. Accessed August 22, 2017.
2. Laursen RP, Larnkjær A, Ritz C, Hauger H, Michaelsen KF, Mølgaard C. Probiotics and child care absence due to infections: a randomized controlled trial. 2017;140(2): e20170735. doi:10.1542/peds.2017-0735.