Hepatitis B Virus (HBV) Transmission Rate among Children Born to Chinese-American Mothers

1
Hepatitis B Virus (HBV) Transmission Rate among
Children Born to Chinese-American Mothers with
Chronic Hepatitis B (CHB) in the New York
Downtown Area Li-Jun Mi, MD, PhD1, Jeffrey
Karsdon, MD2, William M. Huang, MD3, Betty
Chiang, MD4, Marc G. Ghany, MD, MSci5, Giuseppe
DelPriore, MD, MPH3, Peter Wong, MD3, Eric Poon,
MD6,7, Michelle Leong, RN7, Robert S. Brown, MD,
MPH8 1Out-Patient Division, Dept. of Medicine,
2Neonatology, Dept. of Pediatrics, 3 Dept. of
Obstetrics Gynecology, 6Dept. of Pediatrics,
New York Downtown Hospital, New York 4Hepatitis
Medical Sciences, Gilead Sciences, Inc., Foster
city, CA 5Liver Disease Branch, National
Institutes of Health, NIDDK, Bethesda, MD
7Chinese Community Partnership for Health, New
York 8Division of Liver Disease and
Transplantation, Columbia University Medical
Center, New York
INTRODUCTION
RESULTS
Table 2. Prenatal Characteristics of 599
Chinese-American Mothers with CHB in the New York
Downtown Area
Perinatal transmission is the most frequent
source of HBV infection worldwide, with reported
rates of 3-39, despite newborns receiving
standard passive-active immunoprophylaxis and
vaccination. In the US, about 24,000 infants are
born to mothers with CHB annually, with an
estimated HBV transmission rate of 1. However,
complete and accurate data on the HBV
transmission rate is not available in the US.
Aims 1) Determine the HBV perinatal
transmission rate in Chinese-Americans whose CHB
prevalence is 10-15. 2) Evaluate risk factors
associated with the HBV transmission 3) Identify
impediments to proper follow-up of infants born
to mothers with CHB in this population.
The follow-up approachability of the 599 mothers
is shown in Table 1. More than sixty percent of
the mothers were unable to be contacted. About
37 of those contacted mothers (n175) had sent
their children back to China at age of 3-24
months to be taken care of by extended family
members. As of October 1, 2009, 76 mothers-81
infants pairs were evaluated. HBeAg, perinatal
HBV DNA levels and other maternal characteristics
are shown in Table 2. Seven out of 76 mother
(9.2) delivered 8 babies (9.8) whose HBsAg were
positive by the age of 24 months. Among the
seven mothers, 5 were HBeAg positive, 1 unknown,
and 1 negative. The one with HBeAg- had a
preterm prelabor rupture of membrane. Her baby
became HBsAg- at age of 3 years, and anti-HBs
developed after 6 doses of HBV vaccine.
Perinatal HBV DNA were only available in 3 of
these mothers (all HBeAg ) with 2 at 108 and 1
at 109 copies/ml (Table2). None of these 7
mothers had breastfed, nor had they received
anti-HBV treatment during or within 12 months of
pregnancy. Of those 8 babies who were infected
with HBV, 4 were born to mothers who had mild
peripartum complications (premature prelabor
rupture of membrane, late preterm birth,
oligohydramnios, and amniotic infection,
respectively). Of the remaining 73 babies, 61
(83.6) developed anti-HBs by the age of 36
months, 9 unknown, and 3 were negative for both
HBsAg and anti-HBs despite standard
immunoprophylaxis and vaccination. Among the
mothers with know HBeAg status (n58), HBeAg
showed a higher risk of HBV transmission with an
OR 11.25 (p0.02, 95CI 1.56 77.34).
Total of 599 76 mothers participated 7 whose infants HBsAg
Age (year-old)
mean/- SD (range) 28.4 /-4.6 (17.7 -44.0) 28.9 /-4.7 (20.6-40.9) 29.4 /-5.9 (24.1 -38.0)
20 30 434 (72.3) 58 (77.3) 4
31 40 153 (8.8) 23 (30.7) 3
gt 40 8 (1.3) 2 (2.7) 0
HBeAg Status
data available 336 (56.1) 58 (76.3) 6 (85.7)
Positive 115 (34.2) 21 (36.2) 5 (83.3)
Negative 217 (64.7) 37 (63.8) 1 (16.7)
HBV DNA (copies/ml)
data available 70 (11.7) 29 (38.2) 3
lt 160 17 (24.3) 8 (27.6) 0
160-108 37 (52.9) 13 (44.8) 0
gt 108 17 (24.3) 8 (27.6) 3 (100)
ALT (U/L)
date available 70 (11.7) 49 (64.5) 5 (71.4)
mean/- SD (range) 28.6 /-20.6 (8 -131) 26.8 /-12.9 (8 -73) 26.6 /-11.4 (15 - 45)
lt 45 62 (88.6) 43 (56.6) 4
gt/ 45 8 (11.4) 6 (12.2) 1

METHODS
In this retrospective study, newborns at risk for
HBV infection were identified by merging two
databases at New York Downtown Hospital (NYDH)
pregnant women with CHB, and newborns receiving
hepatitis B immune globulin (HBIG). 641 babies
were born to 601 mothers with CHB (mean age 28.9
years) at NYDH from September 1, 2005 to December
31, 2007. All 599 mothers of Chinese descent
were invited by letter, followed by phone calls
to participate. Maternal HBeAg, anti-HBe, HBV
DNA, ALT levels, history of anti-HBV treatment
prior to delivery, perinatal complications,
breastfeeding and presence of any infected family
member(s) were recorded. Infants HBsAg and
anti-HBs results at 6-36 months were obtained
from pediatricians records. The study was
approved by the NYDH IRB and all mothers provided
written informed consent.
CONCLUSION AND DISCUSSION
The overall HBV transmission rate of 9.2 in this
Chinese-American population despite standard HBV
immunoprophylaxis at birth and adequate
vaccination, is much higher than previously
reported in the US. Mothers with positive HBeAg
are at higher risk of HBV transmission to the
newborns (OR11.25). Therefore, it should be
highly recommended that HBeAg status be tested in
all pregnant women with CHB, and if possible, the
HBV DNA level. Due to incomplete follow-up,
possible bias may affect the actual rate.
Multiple socioeconomic factors represent major
barriers to adequate follow-up in this population.
Table 1. Follow-up Approachability of 599
Chinese-American Mothers with CHB in the New York
Downtown Area
Number
Total in Database 599 100
Letters undeliverable 47 7.8
Phone changed/non-working 350 58.4
Total Contacted 175 29.2
came for study 76 43.4
will come for study 39 22.3
unable to make the visit 50 28.6
declined to participate 10 5.7
children sent back to China 65 37.1
Acknowledgement This study is partially
sponsored by Gilead Science, Inc. We are
thankful to Ms. Wan Leung for her assistance in
contacting to the subjects. We also appreciate
the File Room staff and nursing staff in
Neonatology unit for access to the medical
records.