Generally, the progression of<unk>  starts with bacteria colonizing the gastrointestinal tract. The bacteria then invades through the intestinal mucosa layer into the blood, causing bacteremia followed by invasion of the cerebrospinal fluid. The neonate's less efficient immune system (especially the alternative complement system) lessens their defense against invading bacteria. Colonization of the mother plays an important role in transmission to the neonate, causing early-onset<unk> . Group B Streptococcus Neonatal Streptococcus agalactiae infection is acquired in utero or during passage through the vagina. Evidence suggests that vaginal colonization by Streptococcus agalactiae during pregnancy increases the risk of vertical transmission and early-onset disease in neonates.<unk> -causing E. coli Some strains of E. coli have a capsule, called K1, which protects the bacteria from the innate immune system and allows it to penetrate the central nervous system. The capsule contains sialic acid, which is found widely in humans and so does not set off the defenses of the body. Sialic acid also plays a role in the bacteria's ability to invade through the blood-brain barrier. The capsule can be variably O-acetylated.
Neonatal meningitis
Neonatal stroke
Shaken baby syndrome
Neonatal encephalopathy
Omphalitis of newborn
Hemolytic disease of the newborn 
Hemolytic disease of the newborn
Neonatal sepsis