The Association Between Lactational Infective Mastitis and the Microbiome: Development, Onset, and Treatments

Lactational infective mastitis (LIM) was previously thought to occur due to trapped milk causing inadequate milk drainage and consequent infection. However, advances in genome sequencing techniques have shown that the abundance of Staphylococcus aureus, Staphylococcus epidermidis, Lactobacilli species, and Bifidobacterium species in the breast milk of lactating women play a key role in the development of LIM. Recent discoveries have revealed that the breast milk microbiome is composed of bacteria and other microorganisms, which are seeded through multiple pathways and are influenced by maternal factors. An imbalance in the microbial abundance in breast milk can lead to LIM. Given that this infection can cause early termination of breastfeeding, it is imperative to discuss prevention and treatment options. The objective of this review is to highlight the pathogens involved in LIM affecting human mothers, routes of bacterial transfer, and contributing factors that may influence changes in the composition of the milk microbiota, as well as propose preventative and curative treatment options.