TORCH information, Herpes Virus

Herpes Simplex Virus (HSV)

Herpesvirus infections are among the most common viral infections in humans. They are spread by oral or genital contact. It is estimated that between one in 1,000 and one in 5,000 infants are born with HSV infections. About 80 percent of these infections are acquired during the birth process itself; the virus enters the infant through its eyes, skin, mouth, and upper respiratory tract. Of infants born with HSV infection, about 20 percent have localized infections of the eyes, mouth, or skin. About 50 percent of infected infants will develop the disease throughout the body (disseminated) within nine to 11 days after birth. Disseminated herpes infections attack the liver and adrenal glands, as well as other body organs. Without treatment, the mortality rate is 80 percent. Even with antiviral medication, the mortality rate is still 15 to 20 percent, with 40 to 55 percent of the survivors having long-term damage to the central nervous system. In order to begin early, effective treatment, it is critical for pediatricians to diagnose HSV infection in newborns as soon as possible.

Performing the TORCH panel requires obtaining a sample of the infant's blood. Samples from infants are usually obtained by the heelstick procedure when only a small quantity of blood is needed. The baby's foot is wrapped in a warm cloth for five minutes to bring blood to the surface and help it to flow more easily. The foot is then sterilized with an alcohol swab and a lancet is used to puncture the baby's heel on one side, avoiding the center of the heel to prevent inflammation of the bone. The blood sample is drawn in tiny capillary tubes, properly labeled, and taken to the laboratory for testing. In rare instances, a phlebotomist is not able to draw sufficient blood from a heel puncture, and a physician may draw venous blood from a femoral vein in the groin area or another vein larger than veins in an infant's arms.

Since the TORCH test is a screening or first-level test, the pediatrician may order tests of other body fluids or tissues to confirm the diagnosis of a specific infection. In suspected cases of toxoplasmosis, rubella, or syphilis, cerebrospinal fluid may be obtained from the infant by spinal tap in order to confirm the diagnosis. A diagnosis of CMV is usually confirmed by culturing the virus in a sample of the infant's urine. In HSV infections, tissue culture is the best method to confirm the diagnosis.