In Lao People's Democratic Republic, hepatitis B virus is highly endemic. However, blood donations are only screened for HBsAg, leaving a risk of transmission by HBsAg-negative occult infected donors. Here, we characterized first-time blood donors to assess prevalence of hepatitis B virus infections and occult infected donors.
2. Journal Scan
Occult hepatitis B infections among blood donors in
Lao PDR
R.N. Makroo a,
*, Vikas Hegde b
, Aakanksha Bhatia c
a
Director, Senior Consultant, Department of Transfusion Medicine, Indraprastha Apollo Hospitals, Sarita Vihar,
New Delhi, India
b
DNB Resident, Department of Transfusion Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, New Delhi,
India
c
Sr. Registrar, Department of Transfusion Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, New Delhi,
India
a r t i c l e i n f o
Article history:
Received 16 April 2014
Accepted 21 April 2014
Available online 3 June 2014
Occult hepatitis B infections among blood donors in Lao PDR. Jutavijittum P, Andernach IE, Yousukh A, Samountry B,
Samountry K, Thammavong T, Keokhamphue J, Toriyama K, Muller CP. Vox Sang. 2014 Jan;106(1):31e37. http://dx.doi.org/10.
1111/vox.12073. Epub 2013 Aug 12.
Abstract
Background and objectives: In Lao People’s Democratic Republic, hepatitis B virus is highly endemic. However, blood do-
nations are only screened for HBsAg, leaving a risk of transmission by HBsAg-negative occult infected donors. Here, we
characterized first-time blood donors to assess prevalence of hepatitis B virus infections and occult infected donors.
Materials and methods: Sera were screened for HBsAg, HBeAg and anti-HBs, anti-HBc and anti-HBe antibodies. Occult HBV
infections (OBIs) were assessed in HBsAg-negative sera by PCR, and sera of HBsAg positive and occult infected donors were
phylogenetically characterized.
Results: 9.6% of the donors were HBsAg positive, and 45.5% were positive for at least one of the hepatitis B virus serum
markers. More than 40% HBsAg carriers were HBeAg positive, with HBeAg seroconversion occurring around 30 years of age.
Furthermore, 10$9% of HBsAg-negative, anti-HBc and/or anti-HBs-positive donors were occult infected with hepatitis B
virus. Thus, at least 3.9% of blood donations would potentially be unsafe, but hepatitis B virus DNA copy numbers greatly
varied between donors.
Conclusion: In Lao People’s Democratic Republic, a sizable proportion of HBsAg-negative and anti-HBc antibody-positive
blood donations are potentially DNA positive and infective for hepatitis B.
* Corresponding author.
E-mail address: makroo@apollohospitals.com (R.N. Makroo).
Available online at www.sciencedirect.com
ScienceDirect
journal homepage: www.elsevier.com/locate/apme
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http://dx.doi.org/10.1016/j.apme.2014.04.001
0976-0016
3. Comments
Occult hepatitis B infection (OBI) is defined as, the presence of
HBV DNA in the individual with HBsAg being below the
detectable limits. Such individuals can be seropositive or
seronegative depending on whether anti-HBsAg antibody is
present or absent in the individual respectively. They may
have anti-HBc antibody present or absent in them. The rele-
vance of screening for anti-HBc antibody has been debated
contrastingly by different authors. In the western part of the
world where HBV is in low prevalence(<2%) the presence of
anti-HBc antibody prompts the discarding of the particular
unit of blood. In highly HBV endemic countries the prevalence
of anti-HBc antibody can be found in up to 40% of the in-
dividuals. The discarding of such a high proportion of units
can’t be afforded by these countries.
The authors in this study have noted that 10.9% of HBsAg-
negative, anti-HBc and/or anti-HBs-positive donors were
occult infected with hepatitis B virus which can be potentially
dangerous if transfused to the patients. They opine that NAT
testing can be a good strategy to exclude this infective blood
from being transfused. However, the question of doing away
with anti-HBc antibody screening remains unanswered.
Our experience is different from the above article. In our
study, 10.22% (9638/94,247) were positive for anti-HBc, of
which, 9.19% (8660/94,247) of donors were positive for anti-
HBc and negative for HBsAg and only 0.15% of anti-HBc posi-
tive and HBsAg-negative donors showed the presence of HBV
DNA in their sera. Majority i.e. 99.85% of these donors were
anti-HBc positive and negative for HBsAg and HBV DNA.
In countries where there is high prevalence of HBV infec-
tion screening for anti-HBc antibody can cause discarding of a
large proportion of units. Though it is said to cover the second
window period (i.e. around 150e180 days after infection when
both HBsAg and HBV DNA falls to minimum levels) its use-
fulness in detecting OBI is questionable. NAT is very useful in
detecting the OBI. Risk-benefit ratio of doing away with anti-
HBc ab screening and implementation of NAT should be
individualized by countries according to their prevalence of
infection and their resources.
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