Prospective cohort study of mother‐to‐infant infection and clearance of hepatitis C in rural Egyptian villages

Abstract

Although persistent transmission of hepatitis C virus (HCV) from infected mothers to their infants is reported in 4–8%, transient HCV perinatal infection also occurs. This prospective cohort study determined perinatal HCV infection- and early and late clearance-rates in 1,863 mother-infant pairs in rural Egyptian villages. This study found 15.7% and 10.9% of pregnant women had HCV antibodies (anti-HCV) and HCV-RNA, respectively. Among 329 infants born of these mothers, 33 (10.0%) tested positive for both anti-HCV and HCV-RNA 2 months following birth—29 (12.5%) having HCV-RNA positive mothers and 4 (with transient infections) having mothers with only anti-HCV. Fifteen remained HCV-RNA positive at one and/or 2 years (persistent infections), while 18 cleared both virus and antibody by 1 year (transient infections). Among the 15 persistent cases, 7 cleared their infections by 2 or 3 years. At 2- to 6- and at 10- to 12-month maternally acquired anti-HCV was observed in 80% and 5% of infants, respectively. Four perinatally infected and one transiently infected infant were confirmed to be infected by their mothers by the sequence similarity of their viruses. Viremia was 155-fold greater in mothers of infants with persistent than mothers of infants with transient infections. Maternal-infant transmission of HCV is more frequent than generally reported. However, both early and late clearance of infection frequently occurs and only 15 (4.6%) and 8 (2.4%) infants born of HCV-RNA positive mothers had detectable HCV-RNA at one and 2–3 years of age. Investigating how infants clear infection may provide important information about protective immunity to HCV.

Mother-to-Child Transmission of Hepatitis C Virus (HCV) Among HIV/HCV-Coinfected Women

“…Our rate is similar to the rates of MTCT of HCV observed in multicenter studies conducted among HIV-uninfected women in Europe [44,45], Egypt [46], and the United States [47]. It is important to emphasize that different definitions of MTCT of HCV used in previous studies could at least partially account for these differences.…”

“…Because most studies base transmission rates on cases with anti-HCV persistence after 18 months of age, there is also a chance that we captured additional cases of infants with transient infection who cleared the HCV virus and did not mount a persistent anti-HCV response [46]. The presence of transient viremia should be regarded as a consequence of spontaneous viral clearance after MTCT [31,36,46].…”

Prospective Study of Prevalence and Risk Factors for Hepatitis C in Pregnant Egyptian Women and Its Transmission to Their Infants

“…At 6 months of life, only 2 (3.8%) were positive for HCV-RNA, indicating persistent HCV infection, while the other 4 infants had cleared their HCV-RNA indicating clearance of perinatal HCV infection. A similar figure for vertical transmission of HCV (4.6%) was reported recently from Egypt at one year of age (12). These results show that a large proportion of infants were only temporarily positive for HCV-RNA during the first weeks of life and the PCR test should be repeated again at 6 months of life.…”

“…The children continuing to have HCV-RNA after the 6-month visit were considered to have persistent perinatal HCV infections. Anti-HCV antibodies detected in the blood of children whose mothers tested positive for anti-HCV antibodies 2-6 months after delivery were considered to be maternally acquired (12).…”

Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Exposed and HIV-Infected Children

“…7,13–21 The primary risk factor for perinatal HCV transmission is maternal HCV viremia at delivery, although an absolute threshold for HCV transmission has not been identified. 14,22–27 Data do not indicate that HCV genotype is related to risk of perinatal HCV transmission. 14,20 Although a few studies have suggested that vaginal delivery increases risk of HCV transmission 13,15,17,22 and that HCV can be transmitted during the intrapartum period, 28 most studies have found that mode of delivery does not appear to influence perinatal HCV transmission.…”