Chlamydia trachomatis infections are among the most common sexually transmitted bacterial diseases. These infections, often marked by a red and swollen area and discharge, can affect the eyes, the lungs, and the genital area. Infections can be transmitted to children either by a sexual partner or from birth by their mother. Nearly two thirds of all births to mothers with the infection result in an infected child. Newborns born with chlamydia trachomatis can show signs of the disease as early as three days after birth and as late as five or six weeks after birth. Antibiotic treatments can cure chlamydia trachomatis in under two weeks, although relapses can occur. If left untreated, pneumonia may develop. Pneumonia from chlamydia trachomatis may require an additional month of treatments and is often considered clinically severe.