Hepatitis B vaccination status and associated factors among undergraduate students of Makerere University College of Health Sciences
Hepatitis B vaccination status and associated factors among undergraduate students of Makerere University College of Health Sciences
Yvette WibabaraID 0 1
Cecily Banura 1
Joan Kalyango 0 1
Charles Karamagi 0 1
Alex Kityamuwesi 0 1
Winfred Christine Amia 0 1
Ponsiano Ocama 1
0 Clinical Epidemiology Unit, Makerere University , Kampala , Uganda , 2 Department of Paediatrics, Makerere University , Kampala , Uganda , 3 Department of Medicine, Makerere University , Kampala , Uganda
1 Editor: Isabelle Chemin, Centre de Recherche en Cancerologie de Lyon , FRANCE
Hepatitis B is a global health problem. Trainees in the health-related fields are exposed to occupational risk of Hepatitis B Virus. In Uganda, there is scarcity of information on vaccination among students in health-care. The objective of this study was to assess hepatitis B vaccination status of the students and factors associated.
Methods and findings
This was a cross sectional study, conducted at Makerere University College of Health
Sciences among undergraduate students who were eligible. A self-report on Hepatitis B
vaccination status and various characteristics were collected on each participant, using a
standardized structured self-administered questionnaire. Descriptive statistics were
computed, bivariate and multivariate analysis were done using Stata 14.
Out of 760 participants, 44.3% (95% CI 35.2?52.8) reported full vaccination. Vaccination
was associated with gender, course, year of study and student?s sponsorship. Males were
less likely to be vaccinated, Prevalence Ratio (PR) 0.79; P-value <0.001, while
self-sponsored students were also most likely to be vaccinated, PR 2.08; P-value <0.001. About 37%
reported an accidental needle injury during their training.
Full vaccination was low and given the high prevalence of needle injuries, it raises a safety
concern. Vaccination should be mandatory for all students prior to clinical exposure. There
is need for targeted interventions to increase uptake.
Funding: The authors received no specific funding
for this work.
Competing interests: The authors have declared
that no competing interests exist.
Abbreviations: Anti-HBs, Antibody to hepatitis B
surface antigen; BDS, Bachelor of Dental Surgery;
BEH, Bachelor of Environmental Health Science;
BMR, Bachelor of Science in Medical Radiography;
BPH, Bachelor of Pharmacy; BSB, Bachelor of
Science in Biomedical Sciences; HBsAG, Hepatitis
B surface antigen; HBV, Hepatitis B Virus;
MakCHS, Makerere University College of Health
Sciences; MBChB, Bachelor of Medicine and
Bachelor of Surgery; NUR, Bachelor of Science in
Nursing; PEP, Post Exposure Prophylaxis; PPE,
Personal Protective Equipment; PR, Prevalence
ratio; SOMREC, School of Medicine Research
Ethics Committee; WHO, World Health
Hepatitis B is a viral infection that attacks the liver. It is a major global health problem, and the
most serious type of viral hepatitis. It is estimated that about 780,000 people die each year due
to consequences of hepatitis B . In Uganda, Hepatitis B infection is highly endemic with a
national prevalence of 10%, with geographical variation across the country ranging from 4% in
the southwest 5% in Kampala and surrounding districts and 25% in Northeast [
Like other health workers, trainees in the health care professions are also exposed to an
equal magnitude of occupational risk of Hepatitis B Virus (HBV), as they work in the same
health care delivery system. In fact, the risk for accidental exposure among the trainees could
be higher due to their lack of experience and insufficient training on how to use Personal
Protective Equipment PPE [
]. A study done among medical students in School of Medicine
Makerere University Uganda found that overall 11% of medical students had hepatitis B
infection defined as Hepatitis B surface antigen (HBsAg) positive[
Uganda?s endemicity for Hepatitis B infection poses a great risk of occupational exposure
to HBV for persons in health-related fields. World Health Organization (WHO) guidelines for
the prevention, care and treatment of hepatitis B infection recommend special consideration
of health-care workers and students for HBV screening and vaccination. However, these
guidelines are not widely implemented in Low and Middle-Income Countries . The Uganda
Ministry of Health?s statutory instrument on hepatitis B requires all health workers and
students to be vaccinated against HBV within six months from the commencement of clinical
There is paucity of information about what the current Hepatitis B vaccination coverage
among students in the health-related fields. Therefore, this study sought to assess the
vaccination status of students in the College of Health Sciences and the factors associated. The study
findings will generate information necessary for formation of policies on vaccination against
Hepatitis B among students in health related fields.
Materials and methods
This was a cross sectional study conducted at Makerere University College of Health Sciences
(MakCHS) from March- April 2018. Makerere is the biggest University in Uganda located in
Kampala district in Central region. Makerere has 9 colleges, one of them being College of
Health Sciences (CHS). The college admits students for various courses including: Medicine
(MBChB), Nursing (NUR), Pharmacy (BPH), Radiography (BMR), Biomedical sciences (BSB)
Environmental Health (BEH) and Dental surgery (BDS). The students are attached to Mulago
hospital which is a National Referral Hospitals also acting as the teaching hospital for the
undergraduate and graduate students for their clinical rotations. Students in BSB undergo
training for 3 years, NUR, BPH and BMR train for 4 years, while MBChB and BDS train for 5
The study involved all undergraduate students in the MakCHS that were in the study area
during the study period who fulfilled the eligibility criteria. We included all consenting students
enrolled in MBChB, BDS, BPH, BMR, BSB and NUR who were found in lecture rooms during
the study period and excluded anyone with a known diagnosis of hepatitis B infection based
on a self-report.
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Ethics approval and consent to participate
Permission to conduct the study was sought from the Clinical Epidemiology Unit, MakCHS.
Institutional ethical approval was sought from Makerere University School of Medicine
Research and Ethics Committee (SOMREC). Approval was granted ref. no. REC REF 2018?
047 Administrative permission to conduct the study was granted by the college principal. All
participants were requested to consent before participating in the study. Confidentiality of
participant information was ensured by not using participants ?names on the questionnaires.
Objective 1 Using Kish Leslie 1965 formula for a descriptive objective, the proportion of
vaccinated students, from literature being 0.39 [
] the required sample size was 365. But since by
nature of the study there was likely to be design effect we adjusted the sample size, using a
design effect of 2, the adjusted sample size to 730 participants and anticipating some none
response, we added 10% making it 803.
We planned to use proportionate stratified random sampling. The study population was to be
stratified on course offered and a proportionate random sample selected from each stratum.
However, during data collection, the turn up of students for lectures was low, so we enrolled
everyone who fulfilled the eligibility criteria.
Dependent variable: Vaccinated, coded as 1 ?Yes? 0 ?No?. All those who had received three or
more doses were coded as ?Yes? while those who had received less than three doses, or never
been vaccinated or not sure of their vaccination status were coded ?No?
Independent variables: Age category, sex, year of study, course, sponsorship, source of
upkeep, religion, marital status, nationality, knowledge category, risk perception, history of
needle prick injury. Knowledge was categorized into ?knowledgeable? if the respondents were
able to answer 70% or more of knowledge questions correctly. ?less knowledgeable? if the
respondents answered less than 70% of knowledge items. The tool for assessment on
knowledge had questions on transmission of hepatitis B, complications and prevention.
Data collection and management
Data collection was done at opportune moments when students had come together for
lectures. The pretested self-administered questionnaires were distributed to all students and
collected immediately to minimize none response. Students who did not consent and those who
had been diagnosed with Hepatitis B returned both the unfilled questionnaire and consent
form. Data was entered into Epidata version 4.2. The raw data was first exported to excel,
cleaned and later imported into STATA version 14.0. for analysis.
The demographic characteristics were described using proportions for categorical data,
median and inter-quartile range for continuous variables. The proportion describing the
vaccination status of participants was computed. Note that because the outcome was not rare
(>20%) a logistic model was not appropriate for analysis. So, we used a modified Poisson
model reporting clustered robust standard errors, significant variables were checked for
interaction, dropped variables were tested for confounding.
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Results and discussion
Out of 820 students that received the questionnaires, 760 (93%) responded, 9 (1%) fulfilled the
exclusion criteria of having Hepatitis B infection, while 51 (6%) did not respond. The median
age of the 760 participants was 23, range (18?42) years. As shown in Table 1, majority were
(65.1%) were males, while about 50.8% (386/760) were MBChB students.
Number (n = 760)
Of the 760 participants, 44.3% (337/760) reported having received all the three doses required
for protection against HBV, 22.5% (171/760) reported partial vaccination, while 33.2% (252/
760) had not received any vaccination against HBV. Of those who were not vaccinated (239/
760), 63.2% stated high cost of vaccine as the most common reason hindering their
vaccination, 9.5% believed they were not at risk while 27% did not know where to find the vaccine.
74.6% of the participants were knowledgeable about hepatitis B infection. Most of the
participants (67.8%) perceived themselves to be at high risk of occupational exposure to hepatitis B,
in addition, 36.7% (279/760) reported having had a needle stick injury while attending to
patients and of these 19.0% (53/279) had taken PEP for HIV. Of those who reported needle
stick injuries, 50% (50/279) were in their last year of training.
As shown in Table 2 as well as Table 3, vaccination was significantly associated with sex,
course, year of study and student?s sponsorship.
The proportion of students who were fully vaccinated was found to be 44.3% (95% CI; 35.2?
53.4). Contrary to the Uganda Ministry of Health?s recommendation of 100% vaccination of
students in the health-related field. This was consistent with findings by Atiba et al. (2014) in
Nigeria where only 39.2% were fully vaccinated. This low coverage implies a low level of
protection against Hepatitis B infection despite the potential risk to occupational exposure, which
calls for intervention by policy makers.
The potential risk of occupational exposure to hepatitis B among these students was also
high with about one third (36.7%) of the participants reporting an accidental needle stick
injury since the beginning of their training. This is slightly lower than the findings in the
Noubiap study (2013) among Cameroonian Medical students which demonstrated needle stick
injury rate of 55.9%. Given the low vaccination completion and the needle stick injuries
among the students in MakCHS, this could lead to continued transmission with eventual
morbidity and mortality from Hepatitis B infection among students.
Among those who reported not being vaccinated, reasons for not receiving vaccination
included high cost of vaccine (63%). Our finding differs from previous studies [
availability was the most cited reason. This is probably because Hepatitis B vaccination service
among the students at MakCHS is not free and there is no organized system for the students to
attain this service. Consequently, more than half the participants were not vaccinated despite
the potential risk of occupational exposure.
Most (67.8%) of the respondents perceived themselves at high risk of occupational exposure
to HBV. The perception is consistent with the fact that the proportion of needle stick injuries
was also high in our study. The variability in the risk perception could be arising from the
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differences in courses of the participants which in turn could explain the variability in their
vaccination status as well.
Male students were about 20% less likely to be vaccinated, with a Prevalence Ratio of 0.79
(p-value 0.001). This was consistent with findings from the study by Atiba et al. (2014) where
females had higher odds of being vaccinated. Probably because generally females are better
health seekers than males [
]. This means that any interventions designed to enhance uptake
of intervention programs like vaccination against HBV among students should be gender
sensitive, in terms of involvement especially to male students.
BDS students had the highest likelihood of being vaccinated with a prevalence ratio of 2.56
(p-value <0.001) followed by BPH, MBChB and BSB compared to BMR. NUR was not
significantly associated with vaccination. This is possibly due to group influence and the difference
in risk perception and knowledge. The findings highlight the need for targeted interventions
for the different subgroups of students.
Year of study was also significantly associated with vaccination. Students in Year III which
is also a clinical year for most courses, were most likely to be vaccinated when compared to
those in Year I, with a prevalence ratio of 3.28 (p-value <0.001) This is probably due to group
influence and the wave of media influence that followed the launch of the statutory instrument
by Ministry of Health declaring mandatory vaccination of health workers in 2014. There was
significant interaction between year of study and course.
Student?s sponsorship was also a significantly associated with vaccination. Privately
sponsored students as well those who sponsored themselves were most likely to report being
vaccinated compared to government sponsored students. Probably these students are provided
sufficient pocket money, or they are self-reliant financially to meet the students? needs
including healthcare needs like vaccination.
Most participants (74.6%) were knowledgeable about Hepatitis B infection. However, there
was no association between knowledge category on hepatitis B and hepatitis B vaccination
status. Our finding differs from previous studies [
] which reported high odds of
vaccination among knowledgeable students. It therefore suffices that increasing knowledge among the
students in MakCHS is not what should be prioritized to improve the vaccination coverage
but rather ensuring that Hepatitis B vaccines are available and affordable.
Strength of the study
The large sample size used for assessment of the vaccination status was adequate, which
minimized the possibility of random error. Also, the data collection tool used was pre-tested and
standardized before being administered which supports the validity of the study findings.
The low coverage coupled with a high prevalence of needle prick injuries raises a safety
concern that needs attention by the policy makers. The main reason for low coverage were high
cost of the vaccine, which calls for free vaccination service.
Vaccination status was assessed based on self-report rather than Antibody to hepatitis B
surface antigen (anti-HBs) status, which could have biased the outcome as some people may
have failed to recall their vaccination history or some may have given false information on the
doses they received. The proportion of those deemed to be fully protected could be different if
assessed based on anti-HBs levels. The other limitation was a low turn up of students which
forced us to enroll everyone who fulfilled the eligibility criteria. It is possible that students that
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were interviewed may have been different from those that we missed, hence a possible bias in
S1 File. This is the questionaire.
We would like to acknowledge the support by the student?s leaders and the participants for
taking part in this study. We are indebted to Makerere University College of Health Sciences
administration for allowing us to conduct this study. We extend our thanks to colleagues at
the Makerere University Clinical Epidemiology Unit who constructively contributed to the
shaping of the project.
Conceptualization: Yvette Wibabara.
Investigation: Yvette Wibabara.
Data curation: Yvette Wibabara, Winfred Christine Amia.
Formal analysis: Yvette Wibabara, Joan Kalyango, Alex Kityamuwesi, Winfred Christine
Methodology: Yvette Wibabara, Cecily Banura, Joan Kalyango, Charles Karamagi, Winfred
Christine Amia, Ponsiano Ocama.
Project administration: Yvette Wibabara, Ponsiano Ocama.
Resources: Yvette Wibabara, Alex Kityamuwesi.
Software: Yvette Wibabara, Alex Kityamuwesi.
Supervision: Cecily Banura, Joan Kalyango, Charles Karamagi, Ponsiano Ocama.
Validation: Cecily Banura, Ponsiano Ocama.
Visualization: Yvette Wibabara, Charles Karamagi.
Writing ? original draft: Yvette Wibabara.
magi, Winfred Christine Amia, Ponsiano Ocama.
Writing ? review & editing: Yvette Wibabara, Cecily Banura, Joan Kalyango, Charles
Kara8 / 9
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