Table 1.

TORCH Pathogens, Transmission Temporality, and Neonatal Outcomes

TORCH Letter	Pathogen (disease)	Transmission temporality	Strong clinical correlates of disease in neonate
T	Toxoplasma gondii (toxoplasmosis)	Greatest risk for congenital anomalies with a maternal third trimester infection	Intra-uterine growth restriction, jaundice, diffuse intracranial/intraparenchymal calcifications, chorioretinitis, hepatosplenomegaly, petechiae/purpura, chorioretinitis
T	Treponema pallidum (syphilis)	Greater risk of congenital disease with acquisition in 2nd trimester or later	Thrombocytopenia, maculopapular rash on palms & soles, Hutchinson’s teeth, hydrocephalus, hepatosplenomegaly, petechiae/purpura, chorioretinitis
O	Parvovirus B19 (Fifth’s Disease)	Greater risk of fetal anemia and non-immune hydrops in the 2nd trimester. Fetal acquisition of infection ~1-3 weeks after maternal infection.	Subcutaneous edema, hydrops fetalis, myocarditis & heart failure, retinal and corneal abnormalities, hepatosplenomegaly, petechiae/purpura, chorioretinitis
O	Zika virus (Congenital Zika syndrome)	Vertical transmission and fetal microcephaly can occur with maternal infection in any trimester	Newest “TORCH” pathogen due to complex and severe neurological injuries of the fetus
R	Rubella virus (Congenital Rubella Syndrome)	Greatest risk with first trimester infection, decreasing risk of vertical transmission as gestation progresses	Sensorineural hearing loss, cataracts, patent ductus arteriosus, pulmonary artery stenosis, myocarditis, microphthalmia, glaucoma, “blueberry muffin rash,” hepatosplenomegaly, thrombocytopenia, petechiae/purpura
C	Cytomegalovirus	Equal risk for congenital anomalies with maternal infection in any trimester Greater risk of congenital disease with primary infection as opposed to reactivation	Microcephaly, periventricular calcifications, sensorineural deafness, Hepatosplenomegaly, petechiae/purpura, chorioretinitis
H	Herpes virus simplex	Worst outcomes linked to perinatal acquisition at the time of birth. Greater risk of congenital disease with primary infection as opposed to reactivation	Skin-eye-mucus membrane lesions, fever, vesicular rash, meningoencephalitis, myocarditis, cataracts, hepatosplenomegaly, petechiae/purpura, chorioretinitis

This table shows the connection between commonly associated “TORCH” pathogens, risk for vertical transmission depending on the time in gestation of maternal infection, and the clinical outcomes observed in the neonate. Abbreviations are shown in the table.