What is the most common bacteria associated with conjunctivitis that develops from day 2 to 5 after birth?

Neisseria gonorrhoeae is the most common bacterium associated with conjunctivitis that develops between 2 to 5 days after birth, often referred to as neonatal conjunctivitis or ophthalmia neonatorum. This condition typically arises from exposure during delivery when the bacteria ascends from the maternal genital tract.

The timing of the onset is critical; conjunctivitis caused by Neisseria gonorrhoeae usually occurs within this 2 to 5-day window, necessitating prompt diagnosis and treatment to prevent complications such as corneal scarring or even blindness.

While other bacteria, such as Chlamydia trachomatis, can also cause conjunctivitis in newborns, the onset usually occurs later, typically after the first week of life. Staphylococcus aureus and Escherichia coli, although they can contribute to other infections, are not the primary pathogens associated with this early presentation of conjunctivitis in neonates. Thus, identifying Neisseria gonorrhoeae correctly emphasizes the importance of recognizing and managing this infection promptly in a clinical setting.