[Vertical transmission of hepatitis C virus]

Few studies have been published on vertical transmission of hepatitis C virus (HCV), although it is the most common cause of hepatitis C in children. We aimed to determine the rate of vertical transmission of HCV in at risk neonates and to assess the effect of possible risk factors.

A prospective follow-up study was conducted in 35 children of seropositive mothers during an 18-month period (July 1997-January 1999). Testing for anti-HCV antibodies was performed with third generation enzyme linked immunoadsorbent assay. HCV-RNA was qualitatively analyzed with reverse transcriptase polymerase chain reaction (RT-PCR) and hepatic enzyme studies.

All the 35 children studied were positive for HCV antibodies at birth. The children became HCV negative at a mean age of 6 months. HCV infection was detected in two children (5.7%). The mother of one of these children had both HCV and human immunodeficiency virus (HIV) infection. Among the 35 seropositive mothers, a risk factor for percutaneous transmission of HCV (parenteral injection, drug addiction, or previous transfusions) was detected in 19(54%) and HIV coinfection was found in 9(26%).

The present study is consistent with other studies that found a vertical HCV transmission rate of approximately 5%, with a greater risk if the mothers had HCV/HIV coinfection or parenteral risk factors. Studies with greater numbers of subjects are required to determine the prevalence of HCV in expectant mothers and the precise rate of vertical transmission. Infected children should be followed up to evaluate the repercussions of HCV infection.