TORCH Infections

Basics

Description

  • An acronym describing a group of infections acquired prenatally, perinatally, or postnatally due to contact with body fluid (blood, vaginal secretions, or breast milk). They result in similar features, including physical and developmental manifestations:
    • Toxoplasmosis: protozoan parasite, Toxoplasma gondii
    • Other (syphilis): spirochete, Treponema pallidum
    • Rubella: rubella virus
    • CMV: cytomegalovirus
    • Herpes: herpes simplex virus (HSV), HIV
  • System(s) affected: skin/exocrine, HEENT, nervous system, GI, lymphatic/heme, renal, cardiac, pulmonary (1)
  • Synonym(s): rubella, also known as German measles; CMV infection, also known as cytomegalic inclusion disease (CID) or cytoplasmic inclusion body disease; syphilis also known as lues

Epidemiology

  • Predominant age: prenatal to infants
  • Predominant sex: male = female

Incidence

  • Toxoplasmosis: 10 to 33/100,000 live births
  • Hepatitis C/B: <0.1/100,000 live births
  • Syphilis (T. pallidum) 8/100,000 live births (2)
  • CMV: 800/100,000 live births; anomalies occur in 10% of infected infants.
  • HIV: 162 infants in 2010

Etiology and Pathophysiology

  • Infections are transmitted transplacentally, via the maternal genital tract or through breast milk (1).
  • Toxoplasmosis: T. gondii protozoan infection results in active multiplication and cyst dissemination throughout host muscle and neural tissue leading to cell death; maternal infection acquired via ingestion of undercooked meat or contact with contaminated cat feces, food, or soil (1)
  • Syphilis: Spirochetes cause inflammatory damage to most organ systems; maternal infection acquired nearly exclusively from sexual contact (2)
  • Rubella: mechanism of damage unclear, possibly secondary to vasculitis; maternal infection through inhalation of aerosol particles
  • CMV: immunosuppressive virus which replicates in leukocytes, secretory glands, and the kidneys; maternal infection through close contact with infected body fluids (1- to 2-year-old children most common source)
  • Herpes: Virus replicates in sensory ganglion; immunologic inability to control replication results in disseminated infection; maternal infection acquired sexually

Risk Factors

  • General: inadequate or incomplete prenatal care
  • Toxoplasmosis: risk of transmission greatest in 3rd trimester; however, effects are more severe with 1st- or 2nd-trimester infection.
  • Syphilis: Risk of congenital infection increases with gestational age, however, is also heavily dependent on the maternal stage of syphilis during pregnancy, with the highest risk occurring with the primary and secondary stages.
  • Rubella: lack of maternal vaccination or exposure to virus in childhood
  • CMV: caring for preschool-aged children during pregnancy; maternal age <25 years; risk of transmission highest in 3rd trimester and with primary maternal infection; effects more severe with 1st-trimester infection
  • Herpes: primary episode of HSV, active genital lesions at delivery, positive HSV serology at delivery and vaginal delivery, invasive perinatal monitoring, prolonged rupture of membranes, premature labor

General Prevention

  • Toxoplasmosis: Avoid handling cat litter and raw meat; avoid consuming raw/undercooked meat and unpasteurized goat milk; wear rubber gloves for meat preparation and gardening.
  • Syphilis: Screen with venereal disease research laboratory (VDRL) or rapid plasma reagin (RPR) test at first prenatal visit, again in 3rd trimester, and with delivery of high-risk mothers; confirm with fluorescent treponemal antibody absorption (FTA-ABS). Give infected, previously untreated pregnant women penicillin G IM, dose 2.4 million units once for primary, secondary, or early latent; 2.4 million units weekly every 3 weeks for late latent and tertiary. Desensitize all penicillin-allergic patients; expert consultation advised
ALERT
  • Antibiotic treatment may provoke early labor or fetal distress (Jarisch-Herxheimer reaction), but therapy should not be delayed and pregnancy is not a contraindication (3)[A].
  • Rubella: Test IgG titers to determine immunity at initial prenatal visit. Vaccinate nonimmune patients prior to pregnancy or during the immediate postpartum period.
  • CMV: Avoid prolonged exposure to young children during pregnancy; hand washing; insufficient evidence for immunoglobulin or vaccine use (4)[A]
  • Herpes: Cesarean delivery for active genital lesions decreases transmission; insufficient evidence that oral antiviral prophylaxis decreases neonatal herpes incidence, although it does decrease viral shedding, clinical lesions, and number of cesarean sections. Prophylactic treatment with acyclovir 200 mg QID or 400 mg TID or valacyclovir 500 mg BID starting at 36 weeks’ gestation. Recommend treatment with acyclovir of the asymptomatic neonate delivered to mother with active lesions until neonatal polymerase chain reaction (PCR) and viral cultures are negative and maternal serology and PCR indicate a recurrent episode.

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