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Introduction

Project background and significance

Project Introduction

Why CradleShield matters

Background: The Hidden Burden of Pediatric AAD

Antibiotic-associated diarrhea (AAD) is the most common adverse effect of antibiotic therapy in children. A 2025 PLoS One study reports the incidence ranges from 27% to 83% depending on the definition used — meaning one in three children on antibiotics may experience diarrhea.

In China, a 2024 study in the Chinese Journal of Contemporary Pediatrics found that among hospitalized infants, the incidence reaches 20-30%. This translates to millions of children each year suffering from diarrhea, dehydration, interrupted treatment, and increased healthcare costs.

Key references: PLoS One 2025 (PMID:40465685); Chin J Contemp Pediatr 2024.

1 in 3

children on antibiotics
affected by AAD

The Problem: Why Current Probiotics Fall Short

The only probiotics recommended by ESPGHAN for pediatric AAD are Lactobacillus rhamnosus GG and Saccharomyces boulardii (Szajewska et al. 2023). However, both have inherent limitations:

Antibiotic-sensitive

LGG is killed by cephalosporins and amoxicillin (Drago et al. 2011).

Cold-chain dependent

S. boulardii loses viability at room temperature (Feed Industry 2008).

Slow onset

They require colonization to work, while gut barrier damage occurs within 48h (Pradhan et al. 2020).

These three physical bottlenecks leave parents trapped in uncertainty: Should I refrigerate? Should I wait 2 hours? Why is my child still having diarrhea?

Our Inspiration: Listening to Real Voices

“My child had diarrhea for a week after taking cephalosporins. What should I do?”

— Real comment from Xiaohongshu

This question, repeated across social media and echoed in our interviews with pediatricians and parents, became the spark for CradleShield. We realized that behind every statistic is a family struggling with a problem that shouldn't exist.

“Parents constantly ask: ‘We gave probiotics, but the diarrhea persists – is it useless?’”

— Dr. Wang Meng, Pediatrician

Our human practices work (detailed in the HP page) confirmed that the need is real, widespread, and urgent.

Project Goal

We set out to engineer a probiotic specifically designed for the “antibiotic world” — one that overcomes the three bottlenecks and provides a reliable, safe solution for children. Our engineered Bacillus subtilis aims to:

✓ Be naturally antibiotic-resistant — can be co-administered with cephalosporins.
✓ Require no cold chain — spores stable at room temperature.
✓ Act within 48 hours — on-site butyrate production strengthens the gut barrier.
✓ Be self-limiting — dal auxotrophy ensures no environmental survival.

References

  1. Khanpour Ardestani S et al. PLoS One. 2025;20(6):e0325436. PMID: 40465685
  2. Chinese Journal of Contemporary Pediatrics. 2024;26(10):1080-1085.
  3. Szajewska H et al. J Pediatr Gastroenterol Nutr. 2023;76(2):232-247. PMID: 36219218
  4. Drago L et al. J Chemother. 2011;23(4):211-5. PMID: 21803698
  5. Pradhan S et al. Curr Opin Biotechnol. 2020;61:226-234. PMID: 32088541
  6. Feed Industry. 2008;(04). (S. boulardii stability study)