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*Corresponding author: E-mail: salamakasang2@gmail.com; 
 
 
 

Asian Journal of Immunology 
 
3(1): 291-297, 2020; Article no.AJI.60171 
 

 
 

 

 

Immunological Response to Recombinant Hepatitis 
B Virus (HBV) Vaccine among Vaccinated Adults in 

Kaduna South, Nigeria 
 

Salama K. Ibrahim1*, Yetunde Faidero Isa2, Hosea S. Hamafyelto3, 
 Lohya Nimzing4 and Zakka Sheyin5 

  
1
Hope for the Village Child Foundation, Km 2 along Kachia Road, P.M.B. 500, Kaduna State, Nigeria.   

2
APIN/PEPFAR Laboratory, JUTH, P.M.B. 2076, Jos Plateau State, Jos, Nigeria. 

3
Department of Medical Microbiology, University of Jos, Plateau State, Nigeria. 

4
Department of Microbiology, University of Maiduguri, P.M.B. 1069, Maiduguri, Borno State, Nigeria. 

5
Department of Medical Laboratory Science, University of Jos, Plateau State, Jos, Nigeria. 

 
Authors’ contributions  

 
This work was carried out in collaboration among all authors. Author SKI designed the study, wrote 

the protocol and the first draft of the manuscript. Author HSH performed the statistical analysis. Author 
YFI managed the laboratory analyses of the study. Authors LN and ZS supervised and monitored the 

entire work. All authors read and approved the final manuscript. 
 

Article Information 
 

Editor(s): 
(1) Dr. Darko Nozic, University of Belgrade, Serbia. 

Reviewers: 
(1) Manoj Sharma, CSK Himachal Pradesh Agriculture University Palampur, India. 

(2) Ibrahim M. S. Shnawa, Qassim University, Iraq. 
Complete Peer review History: http://www.sdiarticle4.com/review-history/60171 

 
 
 
 

Received 10 June 2020  
Accepted 17 August 2020 
Published 27 August 2020 

 
 

ABSTRACT 
 

Aim: The aim of this study was to determine the rate of immunological response to recombinant 
Hepatitis B Virus (HBV) vaccine among vaccinated residents of Kaduna South Senatorial district. 
Materials and Methods: This was a cross-sectional study of 180 consented residents of Kaduna 
South Senatorial district, Kaduna State who have been vaccinated with HBV vaccines. Systematic 
sampling technique and written informed consent were used in recruiting subjects for this study. 
Five (5mls) of venous blood was collected from each subject after filling a structured questionnaire. 
Sera obtained from 180 subject were qualitatively assayed for HBV markers using SkyTech profile 
and quantitatively tested for Anti-HBs using ELISA KIT (Enzyme Linked Immunoassay for 
qualitative and quantitative determination of antibodies to Hepatitis B surface Antigen by DIA.PRO 

Original Research Article 



 
 
 
 

Ibrahim et al.; AJI, 3(1): 291-297, 2020; Article no.AJI.60171 
 

 

 
292 

 

in Italy). The results from the laboratory analysis of the specimens were computed using SPSS 
version 21. 
Results: The results represent 51.7% seropositive of HBsAb among subjects with male having 
18.9% and female had 32.8% which statistically showed no significant difference between the 
groups (χ

2
 =3.612,P = .43) see Table 1 .In respect to age, 26 – 30years age grouped had the 

highest sero-conversion rate of 10.0%. This however, was not statistically significant (Table 2) 
(χ

2
=5.604, P = .70). For the number of vaccine shots (Table 3) taken, 40.6% of those who 

completed their vaccination were sero-converted followed by those who took two shots with 4.4% 
while those who had one shot had 6.7% HBsAb (χ

2
 =30.665, P< .001).  Sero-conversion in relation 

to the quantity of HBV vaccine with titre values of ≥100IU/ml had 34.6%while ≤ 100IU/ml had 16.1% 
respectively. The result therefore showed statistically significant difference to the quantity of the 
vaccine administered at χ2 = 6.98, P = .08. In Table 4. 
Conclusion: The findings in the research show that none of the subjects tested positive for 
Hepatitis B envelope Antigen or Hepatitis B envelop antibody. This could due to prior resolved HBV 
infection before the onset of vaccination or a resolved HBV infection mid-way into the vaccination 
process. Low sero-conversion rate was observed which could be due to the inclusion of subjects 
who failed to complete their vaccination. 
 

 

Keywords: Hepatitis B virus; sero-conversion; sero-protection; vaccination; adults. 
 

1. INTRODUCTION 
 
Hepatitis is a general term meaning inflammation 
of the liver. This can be caused by Viruses, 
drugs, and poisons e.tc. Among the many known 
causes of hepatitis, viruses are the most 
important, with Hepatitis B virus being the most 
critical in terms of complications, morbidity and 
mortality. It is 50 to 100 times more infectious 
than HIV and can survive outside the body for at 
least 7 days [1]. 
 
Hepatitis B virus is a member of 
the Hepadnavirus family [2]. The virus particle 
called Dane particle / Virion [3] consist of an 
outer lipid envelope and an icosahedral 
nucleocapsid core composed of protein.                 
The nucleocapsid encloses the viral DNA                   
(a DNA polymerase that has reverse 
transcriptase activity similar to retroviruses). The 
outer envelope contains embedded proteins 
which are involved in viral binding of, and entry 
into susceptible cells [4]. The Hepatitis B virus is 
known as a blood-borne virus because it is 
transmitted from one person to another via blood 
or fluids contaminated with blood. Another 
important route of transmission is from an 
infected mother to a newborn child, which occurs 
during or shortly after birth [5]. 
 
Currently, an estimated 2 billion people 
worldwide have had contact with the virus. 360 
million of such infected persons progress to 
chronicity with about25% of chronic cases 
developing cirrhosis and hepatocellular 
carcinoma [6]. HBV infection is of great concern 

in most developing countries. Sub-Saharan 
countries are reported to be hyper endemic 
(i.e.>8% of the population are infected) [7]. 
Among these Sub-Saharan countries, Nigeria 
has a pooled prevalence rate of 13.6% [8]. 
Though drugs are now available for treatment of 
HBV infection, present treatments are very costly 
and not readily available. However, vaccination is 
now the most effective and economical means 
for the prevention of this disease [9]. WHO in 
1991 recommended the inclusion of Hepatitis B 
vaccines in the national vaccination program in 
all countries with the aim of reducing the global 
impact of HBV infections. 
 
Hepatitis B vaccine is a genetically engineered 
(man-made in the laboratory) piece of the virus. It 
does not contain live virus, thus cannot 
cause hepatitis due to reversion as in some live 
attenuated vaccines. This vaccine works by 
helping the body produce immunity (through 
antibody production) that prevents infection from 
Hepatitis B virus. It is pertinent to note Hepatitis 
B vaccine does not protect from other viral 
infections

1
. There are two types of products 

available for immunization against Hepatitis B: a 
vaccine that confers active immunity and a 
specific immunoglobulin that provides passive 
and temporary immunity while awaiting response 
to vaccine. Hepatitis B vaccines are routinely 
given intramuscularly in the upper arm or 
anterolateral thigh. The buttock must not be used 
because vaccine efficacy may be reduced [10]. 
 
Protection by HBV vaccine is based on the 
production of immunity or antibodies to the 



 
 
 
 

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293 

 

surface protein or outer coat of the virus. This 
outer coat is called Hepatitis B surface antigen or 
HBsAg [11]. Successfully vaccinated individuals 
will be positive for only anti- HBs while persons 
who got immunity as a result of HBV infection will 
be positive for both anti- HBc and anti- HBs [12]. 

 

However, around 10% to 15% of adults fail to 
respond to three shots of vaccine or respond 
poorly. Poor responses are mostly associated 
with age (over 40 years), obesity and smoking 
[13]. Lower sero-conversion rates have also 
been reported in alcoholics, particularly those 
with advanced liver disease [14]. Thus the need 
for post - vaccination testing for HBsAg and anti-
HBs following HBV vaccination. 

 

Though this vaccine is commonly used in 
Nigeria, there is no sufficient data on Nigerian 
subjects regarding immunologic response or lack 
thereof in terms of its immunogenicity [15]. And 
many among those who start to receive the 
vaccine fail to complete the 3 recommended 
doses of the vaccine.Thus the need to study the 
immunological response to HBV vaccine, among 
vaccinated persons, in Kaduna south Senatorial 
District. 
 

2. MATERIALS AND METHODS 
 

2.1 Study Area 
 
Blood random samples were collected from 
residents of Kaduna South senatorial district in 
Kaduna State. Kaduna State is located at 
10°31”N7°

 
26’25”E in north-western Nigeria. The 

population of Kaduna as at the 2006 Nigerian 
census was 760,084 but this is believed to have 
grown to over 1.8 million as of 2013.  Collected 
samples will be appropriately. 
 
2.1.1 Study population 
 

Persons with any history of Hepatitis B 
vaccination who had no knowledge of being 
HBsAg positive and consented to be part of the 
study were included and also excluded subjects 
who had knowledge of being HBsAg-positive, 
above the age of 60, non HBV vaccinated, 
between July and November 20 [16] from 
Kaduna South Senatorial district. 
 
2.1.2 Study design 
 
The study was a hospital based descriptive, 
cross-sectional study that recruited 180 
consenting adults in Kaduna South Senatorial 
district, Kaduna State. 

2.2 Sample Collection 
 

Five (5) ml of venous blood was collected from 
the forearm of one hundred and eighty residents 
of Kaduna South Senatorial district, Kaduna 
State after the signing of a consent form and the 
administration of questionnaire. Collected 
samples were placed in sterile plain tubes and 
labeled appropriately.  The blood samples were 
centrifuged at 2000 rpm for five minutes. Sera 
were separated using automated pipette and 
stored in the freezer at -20°C prior to usage. 

 

All samples were qualitatively tested for five 
Hepatitis B Markers HBsAg, HBsAb, HBeAg, 
HBeAb and HBcAb using HBV 5-Panel test kit 
(SkyTech, USA). Quantity of HBsAb was also 
tested using ELISA KIT (Enzyme Linked 
Immunoassay for qualitative and quantitative 
determination of antibodies to Hepatitis B surface 
Antigen in human serum and plasma by 
DIA.PRO in Italy). 
 

2.3 Qualitative Analysis Using HBV 
Profile Test Kit 

 
2.3.1 Principle of HBV detection with HBV 

profile test kit 
 

The product uses the colloidal gold and 
membrane chromatography technology, 
measures HBsAg, HBeAg in whole blood, serum 
and plasma with dual-antibody sandwich method,  
measures HBsAb with dual – Antigen sandwich 
method and measures HBeAb and HBcAb with 
neutralization competitive inhibition method. 
 

2.3.2 Assay procedure of HBV profile test 
 

The right side of the HBV profile test card were 
placed horizontally from the original package, 
from left to right, respectively corresponding to 
HBsAg, HBsAb, HBeAg, HBeAb, HBcAb. Serum 
was dropped into each of the five sample wells of 
the test board using micropipettes. A drop of 
buffer was added to each of the five wells on the 
test card. The results were observed and 
recorded within fifteen minutes. 
 

2.3.3 Results determination 
 

Negative results for HBsAg, HBsAb, HBeAg 
(sandwich method), were represented with only 
one purple bar at the control line in the control 
(C) zone. While positive results were by 
detecting two purple bars, one in the test (T) 
zone and the other in the control (C) zone.  
Negative  results for HBeAb and HBcAb 
(competition method) was done by detecting  two 



 
 
 
 

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294 

 

purple bars in T and C zone and Positive results 
were by detecting  only one purple bar (control 
line) in the control zone. 

 
2.4 Data Analysis 

 
The data obtained from the study were analysed 
using Statistical Package for Social Sciences 
(SPSS) version 21 (IBM SPSS Inc, 
USA).Proportions were compared using Chi-
square with confidence limit (p-value) of < 
0.05considered significant. 

 
3. RESULTS 

 
Of the 180 respondents, 61 were male while 119 
were female. The overall sero-conversion rate of 
HBsAb 51.7% out of which male had 18.9% 
representing 34 positive rate while female with 
32.8% had 59 tested positive. The results there 
showed no statistically significant difference 
between male and female (χ

2
 =3.612, P = .43) 

see Table 1. The study revealed the highest 

HBsAb sero-conversion rate of 10.0% among the 
age group 26 – 30 years with the lowest              
rate of 3.3% among 16 – 20 years age group. 
This however, was not statistically significant 
(Table 2) (χ

2
=5.604, P = .70). 

 

For the number of vaccine shots, 40.6% of those 
who completed their vaccination were sero-
converted followed by those who took two shots 
with 4.4% while those who had one shot had 
6.7% HBsAb at χ

2
 =30.665, P< .001. This 

showed a significant difference between the 
vaccine shots (Table 3). Protective sero-
protection in relation to the quantity of HBV 
vaccine with titre values of ≥100IU/ml had 34.6% 
while ≤ 100IU/ml had 16.1% respectively. The 
result therefore showed statistically significant 
difference to the quantity of the vaccine 
administered at χ2 = 6.98, P = .08. In Table 4. 
This study did not recruit equal number of 
respondents in the one shot, two shots and three 
shots category and did not take into 
consideration other the cellular and genetic 
factors that influence sero-conversion. 

 

Table 1. Sero-conversion of adult subjects to HBV vaccine in relation to gender 
 

Gender No. tested for HBsAb No positive for HBsAb % positive 

Male 61 34 18.9 
Female 119 59 32.8 

Total 180 93 51.7 
(χ

2
=3.612, P= .43) 

 

Table 2. Sero-conversion of adult subjects to HBV vaccine in relation to age 
 

Age group No. tested 
for HBsAb 

No positive for HBsAb % positive 

16-20 14 6 3.3 
21-25 20 11 6.1 
26-30 34 18 10 
31-35 11 8 4.4 
36-40 20 12 6.7 
41-45 30 16 8.9 
46-50 22 8 4.4 
50-55 14 6 3.3 
≥55 15 8 4.4 

Total 180 103 57.2 
Chi-Square (χ

2
) =5.604, P=.70 

 

Table 3. Sero-conversion of adult subjects to HBV vaccine in association with the number 
vaccine shots received 

 

No of shots received No. tested   for 
HBsAb 

No positive for 
HBsAb 

% positive 

One 47 12 6.7 
Two 27 8 4.4 
Three 106 73 40.6 

Total 180 93 51.7 



 
 
 
 

Ibrahim et al.; AJI, 3(1): 291-297, 2020; Article no.AJI.60171 
 

 

 
295 

 

(χ
2
=30.665, df = 2, P< .001) 

Table 4. Protective sero-conversion in association with quantity of HBsAb produced after 
vaccination 

 

Quantity of 

HBsAb 

No. tested   for 
HBsAb 

No positive for 
HBsAb 

% positive 

<100 94 29 16.1 

>100 86 64 34.6 

Total 180 93 51.7 
χ

2
 =13.98, P = .08 

 

4. DISCUSSION 
 
The rate of sero-conversion for all subjects 
observed by this study was 51.7% (93/180) 
regardless of the number of vaccine shots 
received.  None of the subjects tested was 
positive for Hepatitis B envelope Antigen 
(HBeAg) or Hepatitis B envelop antibody. This 
showed that none of the subjects was at the 
infectivity phase or has recovered from the 
phase. This could be as a result of prior resolved 
HBV infection before the onset of vaccination or 
a resolved HBV infection mid-way into the 
vaccination process. 

 
In this study, the 18.9% rate of sero – conversion 
among male subjects lower than 32.8% sero – 
conversion rates recorded in female subjects. 
This was in agreement with findings of [16]                    
who suggested that the high level of testosterone 
in men represses transcription factors                    
implicated in immune activation and with      
findings by [17] that found higher rates of sero-
conversion in women than men. However, this 
study agrees with that by 

15
who found that men 

were more likely to sero-convert to HBsAb than 
women. 

 
The highest rate of sero –conversion of 10.0% in 
age group 26 – 30 years had no relationship with 
sero – conversion after HBV vaccination as was 
found by [18,19]. This finding may be as a result 
of active immunity as a result of physical 
exercise possessed by the older subjects in this 
study. 

 
The number of HBV vaccine shots received                
by subjects was analyzed in this study. Result               
of the analysis showed that there is a               
relationship between the rate of sero-             
conversion and the number of vaccine shots 
received [7]. This buttresses the importance of 
completing the course of vaccination as 40.6%of 
the subjects who completed their vaccination 
sero-converted and just 6.5% of those who 

received just one shot of the vaccine sero-
converted. 

 
In this study, sero-conversion of 34.6%                 
(64/180) with titre values of ≥100IU/ml of                 
HBsAb (level deemed protective by the 
European Health Sector) was lower than the               
85-90% of full response of vaccinated              
individuals as reported [20] and the 82.9% [21]. 
This low sero-conversion rate reported by this 
study may be as a result of the inclusion of 
subjects who received one or two shots of the 
vaccine.  
  

5. CONCLUSION 
 
It was concluded based on the findings                      
that none of the subjects tested were positive             
for Hepatitis B envelope Antigen (HBeAg) or 
Hepatitis B envelop antibody. This could be                  
as a result of prior resolved HBV infection               
before the onset of vaccination or a resolved 
HBV infection mid-way into the vaccination 
process. Low sero-conversion rate was observed 
which could be as a result of the inclusion of 
subjects who received one or two shots of the 
vaccine. 

 
CONSENT 
 
All the authors reviewed and gave their consent 
for this article to be submitted for publication. 

 
ETHICAL APPROVAL 
 
Before the commencement of the project, 
relevant ethical approval was sought for and 
obtained from the Kaduna State Ministry of 
Health. 

 
COMPETING INTERESTS 
 
Authors have declared that no competing 
interests exist. 



 
 
 
 

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provided the original work is properly cited. 
 
 

 

 
 

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