Open AccessHorizontal Transmission of Hepatitis B Virus From Mother to Child Due to Immune Escape Despite Immunoprophylaxis
Author(s) -
Kanji Jamil N.,
Penner Robert E.D.,
Giles Elizabeth,
Goodison Karin,
Martin Steven R.,
Marinier Eric,
Osiowy Carla
Publication year - 2019
Publication title -
journal of pediatric gastroenterology and nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.206
H-Index - 131
eISSN - 1536-4801
pISSN - 0277-2116
DOI - 10.1097/mpg.0000000000002318
Subject(s) - viral quasispecies , medicine , hepatitis b virus , transmission (telecommunications) , transplacental , virology , immune system , vaccination , population , immunology , virus , hepatitis b , immune escape , pregnancy , fetus , biology , genetics , hepatitis c virus , placenta , environmental health , electrical engineering , engineering
Hepatitis B virus (HBV) vaccination starting at birth is approximately 95% effective in preventing mother‐to‐child transmission to infants born to HBV‐infected mothers. A higher risk of transmission is associated with birth to a highly viremic mother, often due to transplacental exposure, while later horizontal transmission is much less common, particularly following complete vaccination. This study reports a case of infection in an older child despite appropriate immunoprophylaxis starting at birth and an apparent protective immune response post‐vaccination. Two immune escape mutations within the antigenic determinant of the surface antigen‐coding region were observed in the child's dominant HBV sequence, whereas the maternal HBV variant lacked mutations at both sites. Ultra‐deep sequencing confirmed the presence of 1 mutation at low levels within the maternal HBV quasispecies population, suggesting early exposure to the child followed by viral evolution resulting in immunoprophylaxis escape and chronic infection.