Mother-to-child transmission of hepatitis C virus : a European epidemiological collaboration
Hepatitis C virus (HCV) infection is a major public health problem worldwide yet little is known about mother-to-child transmission of HCV. This thesis aims to investigate mechanisms of mother-to-child transmission of HCV and the consequences for children born to HCV infected women and is based on data from the European Paediatric HCV Network (EPHN) prospective study. Since 1999, over 1800 HCV infected pregnant women have been enrolled at 33 EPHN clinical centres in 7 countries. Their children were followed up every 3-6 months until 18 months of age and thereafter infected children were seen at least every six months, with clinical and laboratory information collected at each visit as per protocol. The overall risk of mother-to-child transmission of HCV was 6.2% (95% CI 5.0 - 7.5%). Girls were twice as likely to be infected as boys but neither mode of delivery or breastfeeding were associated with the risk of transmission. Among 266 vertically infected children (aged up to 15 years) the prevalence of clinical signs and symptoms was low hepatomegaly was reported in 10% (25), frequently with abnormal alanine aminotransferase results. An estimated 21% (95% CI 15 - 29%) of infected children had evidence of HCV-RNA clearance. Lymphocyte levels up to age 2 years were significantly higher in HCV infected children, girls and children born to HCV/HIV co- infected women. In a survey of parents/carers of children enrolled in the EPHN, a major shortfall in provision of information was identified. The preferred option for long-term follow-up of infected children was to continue visiting the paediatrician regularly and later transfer to adult care, rather than postal or telephone contact or data linkage. This work will inform the clinical management of HCV infected women and their children and provides evidence regarding the most appropriate approach to monitor the long-term consequences of vertically acquired HCV infection.