Why is erythromycin ophthalmic ointment routinely administered shortly after birth?

Erythromycin ophthalmic ointment is routinely administered shortly after birth specifically to prevent gonococcal ophthalmia neonatorum, which is a severe eye infection caused by the bacterium Neisseria gonorrhoeae. This condition can lead to serious complications, including blindness, if left untreated. The administration of this antibiotic ointment is a proactive public health measure, as it protects newborns whose mothers may be asymptomatic carriers of gonorrhea, ensuring the health and safety of the infant.

While erythromycin can have roles in addressing other infections, such as chlamydia, the primary reason for its use in neonates is the prevention of gonococcal infections. The formulation is effective in providing a protective barrier against infections that the newborn may be exposed to during delivery, particularly in cases where the mother has an untreated infection. Thus, the correct answer effectively highlights the specific purpose of erythromycin ointment in the immediate postnatal care of newborns.