Newborn Infants Harbor Dangerous Antibiotic Resistance Genes Within Hours of Birth Greek Study Reveals

Study at ESCMID Global 2026 finds high levels of antibiotic resistance genes in newborns' first stool samples, linked to maternal and hospital factors.

By: AXL Media

Published: Apr 20, 2026, 8:16 AM EDT

Source: Information for this report was sourced from ESCMID Global

Challenging the Sterile Womb Hypothesis Through Genetic Snapshot

A groundbreaking study presented today at the ESCMID Global 2026 congress in Munich has demonstrated that antibiotic resistance genes (ARGs) are present in newborns within the first hours of life. Historically, meconium—the initial stool passed by an infant—was considered sterile, but new molecular screening of 105 infants admitted to a neonatal intensive care unit (NICU) has overturned this assumption. Lead author Dr. Argyro Ftergioti, from the Aristotle University of Thessaloniki, explained that these findings provide a critical "snapshot" of the earliest microbial and genetic exposures, suggesting that the neonatal gut is a fertile ground for resistance markers even before the first feeding.

Maternal and Hospital Factors Driving Early Resistome Development

The research, conducted between July 2024 and July 2025, identified that the collection of resistance genes in newborns is largely influenced by maternal transmission and the clinical environment. Dr. Ftergioti’s team screened for 56 different genes and found a median of eight resistance markers per sample. Notably, maternal hospitalization during pregnancy was linked to the presence of the msrA gene, which is associated with macrolide resistance. This indicates that the mother's own exposure to healthcare-associated microbes plays a direct role in seeding the infant’s internal microbiome with potentially harmful genetic material.

High Prevalence of Resistance to Last Line Antibiotics

The prevalence of specific resistance genes was described by the researchers as striking and concerning. The oqxA and qnrS genes were detected in nearly all infants, found in 98 percent and 96 percent of samples respectively. Even more alarming was the detection of carbapenem resistance genes—associated with last-line antibiotics—in 21 percent of the newborns. According to Dr. Ftergioti, the presence of these clinically important enzymes so early in life suggests that a complex resistome is established well before any medical intervention, presenting a significant challenge for future neonatal infection management.