Table 2.

Selected factors modifying the development and shaping of the skin microbiome

Factors		Commentary
Individual	Age	The skin microbiome evolves over the years according to the changes of skin structure and functions [50], becoming similar to that of adults by the age of 12–18 months [51]
	Skin microenvironment	The skin microenvironment is regulated by skin adnexa, so it depends on anatomical area, gender, ethnicity [52] Sebum and changes in water content are important factors shaping the environment for bacteria, which implies that differences exist among various skin areas [48, 49] Propionibacterium and staphylococci dominate in sebum-rich areas, while Corynebacterium and Staphylococci prevail in dry locations [45, 49]
Environmental	Mode of delivery	The skin of an infant delivered naturally is colonized by bacteria that dominate in the vagina (Lactobacillus, Prevotella and Sneathia), while Staphylococcus, Corynebacterium, and Propionibacterium dominate in the case of Caesarean section [49]
	Diet	Because diet impacts upon the gut microbiome, it is difficult to disentangle its direct effect on the skin microbiome. There is a lack of data suggesting a link between skin microbiome and method of feeding, including the influence of breast milk microbiome on the development of a skin microbiome