Agent

Transmission

Trimester Effect

Neonatal Classic Features

Diagnosis

Treatment

Prevention

Toxoplasma gondii (protozoa) 🧠

Raw meat, cat feces ❌

1st ❌ → fetal death; 3rd ✅ → ↑ transmission

🗝️ Tetrad: Hydrocephalus, Chorioretinitis, Intracranial calcification, Convulsions

IgG/IgM, PCR (AF, blood), imaging

Spiramycin (pregnant), Pyrimethamine + Sulfadiazine + Folinic acid (neonate) ✅

Avoid raw meat, cats

Rubella virus ✅

Respiratory droplets, placenta

1st ❌ → severe CRS

CRS: Cataracts, Deafness, Cardiac defects, Microcephaly

Serology (IgM), maternal history

Supportive only ❌

Rubella vaccine ✅

CMV (DNA herpesvirus)

Saliva, urine, placenta

1st ❌ → severe; 3rd ✅ ↑ transmission

IUGR, microcephaly, calcifications, jaundice, hepatosplenomegaly, chorioretinitis

PCR, IgM, virus culture, IgG avidity

No specific, supportive, antivirals in some

Hygiene

HSV (DNA herpesvirus)

Genital contact, placenta, birth canal

Primary infection ❌ high risk; reactivation lower

Vesicles, CNS defects, microcephaly, hydranencephaly

PCR, viral culture, CSF, EEG, neuroimaging

Acyclovir (IV → oral suppressive)

C-section if active lesions

Treponema pallidum (spirochete)

Transplacental, birth canal

Any stage; 2nd stage = 60–100% risk

Early: rash, snuffles, hepatosplenomegaly, bone lesions 🧠

VDRL/RPR (nontreponemal), FTA-ABS (treponemal)

Penicillin G ✅ (IV/IM)

Antenatal screening

VZV (DNA herpesvirus)

Placenta, perinatal, postnatal

7–20 wks ❌ = congenital varicella

Skin scars, limb hypoplasia, CNS defects

PCR, vesicle culture, maternal history

VZIG (if exposed close to delivery), Acyclovir

VZIG, maternal immunization