https://orcid.org/0000-0002-1205-3367
ABSTRACT
Background
Health care workers (HCWs) are at high risk of Hepatitis B virus (HBV) transmission. Hepatitis B vaccination is effective in protecting against HBV infection. Different factors influence HCW vaccination status such as lack of knowledge & awareness, cost, availability, and hesitancy. This study aimed to determine Hepatitis B vaccination status and factors influencing vaccination status in HCWs of two secondary care hospitals at Sindh, Pakistan.
Methods
A cross-sectional study was conducted in two secondary care hospitals of Sindh, Pakistan. A total of 252 doctors, nurses, laboratory, and other HCWs were asked about the HBV vaccination coverage using a structured tool. Multivariable ordinal logistic regression was used to determine the association of participant’s characteristics, vaccination knowledge with HBV vaccination coverage considering p-value ≤0.05 significant. Odds ratios with 95% confidence interval (CI) were reported.
Results
Our study found that 64.9% doctors, 75.18% nurses, 58.3% allied HCWs, 40.0% laboratory staff, and 70.8% housekeeping staff were completely vaccinated. HCWs stated job entry requirement as the primary reason for complete vaccination (AOR 4.6, 95% CI 1.5–5.3) from the disease. HCWs working in Aga Khan hospital Karachi and who have received vaccination before working in that hospital had four-time higher odds for hepatitis B vaccination (AOR 4.3, 95% CI 1.7–4.9).
Conclusion
Two-third of the HCWs were completely vaccinated in secondary care hospitals in Sindh, Pakistan. Hepatitis B vaccination should be made a job entry requirement to achieve more complete vaccination numbers. Vaccination policies require to implement for all part-timers and full-timer health care workers.
Introduction
Hepatitis B infection is one of the major public health concerns, which causes serious health problems globally.Citation1 According to the most recent estimate, globally 2 billion people have serologic tested evidence of hepatitis B virus infection and about 360 million people have or are at risk of developing a chronic liver infection.Citation2,Citation3
Hepatitis B prevalence in developing countries including parts of Asia and Africa is around 20% of the general population.Citation4 In the African region specifically, 9% of the total population is infected with Hepatitis B.Citation5 South Asian countries mainly India, Bangladesh, and Nepal have an HBV prevalence rate of 8% in different age groups. It is endemic in Pakistan, 5% of the total population is infected with Hepatitis B, which constitutes 11 million individuals.Citation6
Health care workers are at greater risk of acquiring HBV infection and transmitting it to their colleagues and susceptible patients.Citation7 The risk of attaining HBV infection in HCWs relies upon the number of exposures with blood or body fluids sustained for the duration of medical procedures. Occupational Hepatitis B infections are estimated to account for about 37% of the HCWs worldwide, and in low middle-income countries (LMICs), 50% of HBV infection among HCWs is attributed to professional exposure that is due to contact with infected patients, infectious materials such as blood, body fluids, and contaminated medical supplies.Citation8
Vaccination for Hepatitis B is essential for the prevention and elimination of the infection. Vaccinating against Hepatitis B is mandatory for all HCWs; however, 24% of Health care workers remain unvaccinated against HBV worldwide.Citation9,Citation10 The health care setup in Pakistan has no specific guidelines for the Hepatitis B vaccination of HCWs. Private hospitals have brought Hepatitis B vaccination into consideration and made it compulsory as a job entry requirement. According to an estimate, 40% of HCWs from public sectors hospitals were completely vaccinated in Pakistan, i.e., three doses.Citation11 A multi-center survey reported 73% coverage of HBV vaccination in HCWs from both public and private hospitals.Citation12
Different factors influence vaccination uptake in HCWs within different health care setups globally, which includes lack of knowledge & awareness, misperceptions, distrust in vaccines, cost & availability of the vaccine, and vaccine hesitancy.Citation13,Citation14
This study aims to determine the Hepatitis B vaccination coverage in HCWs working in two Aga Khan secondary care Hospitals in Sindh, Pakistan, and uncover factors that influence vaccination coverage because the data for the vaccination status of HCWs in secondary hospitals were not available. This study has also included all HCWs, i.e., Doctors, Nurses, Allied HCWs, Laboratory staff, and housekeeping staff, both part-time and full-time workers, to know the actual vaccination difference among occupational categories, which was also not considered in any of the previous studies.
Methods
An analytical cross-sectional study design was used to determine the vaccination coverage, this study was conducted in two Secondary care hospitals in Sindh, Pakistan, operating under the Aga Khan Network. HCW was considered in this study “a person who is associated with a health care system and whose primary intent is to enhance health of sick either directly or indirectly (WHO).” We included HCWs, both male and female, who worked in these two Aga Khan secondary care hospitals as full-time or part-time employees from these distinct categories only; Doctors, Nurses, Allied HCWs, Laboratory staff, and Housekeeping with anti-HBS titers less than 12 mIU and gave consent to participate in the study. HCW who were previously diagnosed with Hepatitis B and C were excluded. The sample size was calculated using the formula n = Za/2 P(1-P)/d2 considering 95% confidence interval and 80% power of the study. Where Za/2 = 1.96, P = .62 (prevalence/coverage in Pakistan 62%) and 1-P = .38 and d2 = 0.002 (precision). The sample size calculated was 230 accounting for non-respondent rate 10% of the calculated sample size was include in final sample size. The final sample size was 252.Citation11,Citation12 Systematic sampling technique was used to enroll participants in the study. A list of HCWs working in these secondary care hospitals was obtained from hospital management. First participant was chosen randomly and next every second HCW in the list was selected (K = 2). The study’s outcome variable was Hepatitis B vaccination coverage determined as not vaccinated, partially vaccinated, and completely vaccinated. Complete vaccination status means HCWs had received three or more doses (booster doses) of the Hepatitis B vaccine. Partially vaccinated means at least one or two doses of the Hepatitis B vaccine. Not vaccinated means those who have not received any dose of the Hepatitis B vaccine.Citation15,Citation16 Independent variables were socio-demographic characteristics of participants, knowledge about Hepatitis B & Vaccination, factors influencing vaccination status, and other recommended vaccination for HCWs. To assess the knowledge, we asked questions related to Hepatitis B and vaccination. This variable was continuous using scores. Cumulative scores were calculated from these responses through a scoring grid. For every correct answer, the score given was 1 and 0 for the wrong answer.
A web-based, structured questionnaire for data collection related to Hepatitis B vaccination status and factors influencing Hepatitis B vaccination. The tool was taken from two research studies conducted in China and Nigeria to determine the Hepatitis B vaccination status and knowledge of Hepatitis B among Health Care Workers.Citation15,Citation17 The questionnaire was modified on two questions, added question “vaccination status of other recommended vaccines”, and removed the question of “religion of the participant.” The modified tool has a Cronbach alpha of 0.8. The original tool/questionnaire was in English and was translated into local languages by language experts for data collection, content validity index (CVI) of the translated tool was 0.9. Pre-testing of the questionnaire was done on 30 Health Care Workers. Written permission from the Chief Operating Officer (COO), Aga Khan Secondary Hospital, Pakistan, was taken to conduct the study in these hospitals. Informed written consent was taken from health care workers before the data collection. To address certain biases proper measures were taken at design and analysis phase of the study in order to maintain quality of the research. To avoid the selection bias, participants were randomly selected using systematic sampling technique. Vaccination coverage and exposure to any sharp injury was also checked in medical records of HCWs to avoid recall bias. Questionnaire was designed in a way that no one can hide information to avoid wish bias. We calculated mean ±SD for all continuous quantitative variables and computed frequencies and percentages for all categorical variables. One-way analysis of variance (ANOVA) test was conducted at p-value 0.05 to check the difference in mean knowledge scores of HCWs regarding Hepatitis B and vaccination. Multicollinearity was checked for all significant covariates at univariate analysis before multivariable analysis. The multicollinearity cutoff was ≤0.8, and there was no multicollinearity present between the explanatory variables. The outcome or dependent variable of the study is ordinal therefore multivariable ordinal logistic regression was performed, which better signifies the association of vaccination status with other covariates. Stepwise model building technique was used, and Akaike’s Information Criterion (AIC) and Bayesian Information Criterion (BIC) statistics were used to assess the goodness of fit of the model by calculating the difference in nested and fit model. We assessed all possible interactions between variables in the primary model. A p-value ≤0.05 was considered significant. Analysis was performed on STATA version 16.
Results
We surveyed a total of 252 Health Care Workers (HCWs) consisting of Doctors, Nurses, Allied HCWs, Laboratory, and Housekeeping Staff. Among the 175 (69.4%) HCWs had complete vaccination status, 67 (26.6%) had partial vaccination status, and 10 (4.0%) were not vaccinated.
Sociodemographic characteristics of participants
The mean (±S.D.) age of the Health Care Workers was 36.2 ± 9.3 years. Of 252 HCWs, 51 (20.2%) were males, while 201 (79.8%) were females. Among those 252 health care workers, 119 (47.2%) were from Aga Khan Maternal and Child Care Center, Hyderabad, and 133 (52.8%) were from Aga Khan Hospital for Women Karimabad, Karachi. HCWs were in five categories, 57 (22.6%) were Doctors, 137 (54.4%) Nurses, 24 (9.5%) Allied HCWs, 10 (4%) Laboratory staff, and 24 (9.5%) Housekeeping staff. The mean (±S.D.) work experience of these health care workers was 6.56 ± 5.69 years. The number of full-time employers was 216 (85.7%), and part-time employers were 36 (14.3%) in those hospitals ().
Table 1. Sociodemographic characteristics of participants (n = 252)
Description of hepatitis B vaccination status and other recommended vaccine
Of 252 total participants, 118 (46.8%) received their first-ever Hepatitis B vaccination dose before working in the hospital. 107 (42.5%) received Hepatitis B first-ever dose after working to hospital. The majority of HCWs received their first-ever vaccine less than 5 years. 56 (22.2%) received within last 3 years and 53 (21.0%) received their first dose 3–5 years ago. The reason for getting vaccinated was due to occupational exposure for 31 (12.3%) HCWs. While 91 (36.1%) vaccinated due to the belief of protecting themselves, their families, and patients. 103 (40.87%) got vaccinated because of job entry requirement. The mean (±S.D.) knowledge score regarding Hepatitis B and Hepatitis B vaccination was 13.6 ± 2.2. Regarding the vaccination status of other recommended vaccination, majority 87 (34.5%) were vaccinated against influenza (annual dose) followed with MMR (Measles, Mumps, Rubella) 27 (10.7%) ().
Table 2. Detail of hepatitis B vaccination status, knowledge score, and other recommended vaccination (n = 252)
Hepatitis B vaccination coverage in health care workers
The coverage of complete Hepatitis B vaccination in Doctors was 64.9%, 75.2% in Nurses, 58.3% in Allied HCWs, 40.0% in Laboratory staff, and 70.8% in housekeeping staff ().
Table 3. Coverage of complete hepatitis B vaccination status among five categories of HCWs
Determinants of hepatitis B vaccination status
The ANOVA test showed no statistical difference in the mean knowledge scores between the HCW categories. The p-value was greater (p-value 0.78) than the significance level.
Multivariable model with significant variable at p-value ≤0.05 is displayed in . Female HCWs have 1.2 times higher odds of complete Hepatitis B vaccination (AOR =1.2, 95% CI: 1.0–3.3) compared to the male HCWs. The primary reason for getting vaccinated was the job entry requirement and the odds of complete vaccination status in HCWs vaccinated due to job entry requirement had four times greater odds (AOR = 4.6, 95% CI 1.5–5.3) compared to other reasons for getting vaccinated. The odds of the complete vaccination status in HCWs working in the general clinics were about three times higher (AOR = 2.7, 95% CI: 1.1–6.8) compared to the HCWs working in other working areas of the hospital.
Table 4. Multivariable ordinal regression reporting adjusted odds ratio with 95% CI for covariates associated with Hepatitis B Vaccination status in HCWs
The final model indicated a significant interaction between secondary hospital type and first-ever Hepatitis B vaccination. Which suggested that the odds of complete vaccination status among HCWs working in Aga Khan hospital Hyderabad and received first-ever Hepatitis B vaccination dose before working in a hospital was 1.3 times (AOR = 1.3, 95% CI 0.5–3.2) as compared to those working in AKMCCC and received their first-ever Hepatitis B vaccination dose after working at the hospital. Similarly, the odds of having complete vaccination status to partially or not vaccinated among HCWs working in AKHWK and received first-ever Hepatitis B vaccination dose after working at the hospital was 0.7 times (AOR = 0.7, 95% CI 0.3–1.6) as compared to those working in AKMCCC and received their first-ever Hepatitis B vaccination dose after working at the hospital. The odds of having complete vaccination status to partially or not vaccinated among HCWs working in AKHWK and received first-ever Hepatitis B vaccination dose before working in a hospital was 4.3 times (AOR = 4.3, 95% CI 1.7–4.9) as compared to those working in AKMCCC and received their first-ever Hepatitis B vaccination dose after working at the hospital.
Discussion
The study revealed that about seventy percent of Health Care Workers were completely vaccinated against Hepatitis B in two Aga Khan secondary care hospitals, which are a good number. The vaccination status of HCWs in this study is better than other studies conducted in Pakistan. The rates of Hepatitis B vaccination in this study are similar to the rates in Europe and North America, including the USA and Canada, which report more than 70% of HCWs complete vaccinated and 90% vaccinated with at least one dose of vaccination.Citation18–20 According to the results, this study’s complete vaccination status rates were higher than in the African region.Citation21 This study suggested that different predictors were associated with complete vaccination status, supported by the literature.
The sex of the participant is associated with HBV vaccination status. Female HCWs were more vaccinated as compared to males. The literature has also mentioned that females were twice greater vaccinated compared to males.Citation22,Citation23 The results of this study suggested that the occupation category is associated with HBV vaccination status. Several studies have supported this finding that Nursing staff is more vaccinated, followed by Doctors compared to other types of HCWs.Citation24
It was evident from this study that the working site of the health care workers has an association with the complete vaccination status. Health care workers who are dealing with patients admitted in the wards or working in the newborn nursery have received three or more doses of HBV vaccination than HCWs working in other working sites of a hospital. Studies have reported that there is a significant association between the working area of a health care worker. Those who are dealing with admitted patients or inpatient settings are more likely to get vaccinated to be at minimum risk of acquiring the disease and transmitting it to the patients.Citation25
In this study, we found that several other factors were associated with Hepatitis B vaccination status. One of the findings of this study indicated that the duration of the first-ever vaccine dose received is highly correlated with HBV vaccination status. We found that those HCWs who have received their first-ever dose within 10 years have complete vaccination status. The finding was consistent with previously reported literature, which demonstrated that protection from occupational exposure and job entry requirement were the reasons for getting Hepatitis B vaccination.Citation17,Citation26 Moreover, there was an association between vaccination acceptance and vaccination against other recommended vaccines with Hepatitis B vaccination. Health care workers who are not reluctant to any vaccine might be a potential reason for association with Hepatitis B vaccination coverage.
In our study, the most significant interaction was between Secondary hospital and when first-ever Hep-B vaccination dose received, indicating that among HCWs working in AKHWK and vaccinated before working in a hospital, the odds of complete to partially or not vaccinated are greatly increased compared to getting vaccinated after working at the secondary hospital. Certain studies have shown agreement that HCWs who are aware of the risk of acquiring the HBV infection or know about Hepatitis B, vaccinated them before joining the hospital to protect themselves, their families, and patients. This indicated that knowledge and awareness about the disease must occur, impacting the coverage of Hepatitis B vaccination among HCWs.Citation27–29 The health care setup in Pakistan has no specific guidelines for the vaccination of HCWs; hospitals in private setup have brought Hepatitis B vaccination into consideration. The complete vaccination status results significant in these hospitals are due to the vaccination policy; all HCWs must follow strict guidelines. Hepatitis B vaccination is necessary and considered a job entry requirement for the Health Care Workers in these hospitals.
Strengths and limitations
One of the study’s significant strengths is that we achieved the required power of the study by achieving the required sample size. Second, there was a representation of all HCWs. We used a robust analysis method with ordered vaccination categories as per the new vaccination guidelines and looked at the complete, partial, and no vaccination status. We also confirmed Hepatitis B vaccination status through the medical records. This study is the first-ever in Pakistan, which has investigated the Hepatitis B vaccination status among HCWs of secondary care hospitals within two different cities of Sindh. Moreover, we tried to identify factors that influence Hepatitis B vaccination coverage, such as cost, knowledge about Hepatitis B disease, and vaccination. We have also adopted a modified questionnaire that was used by previous studies. There are certain limitations to the study. First, the study is cross-sectional; it can only provide associations. Second, the study took place at only two secondary care hospitals, so the generalizability of the study findings is limited to only HCWs of secondary hospitals. Since the knowledge score covariate was insignificant, we do not have enough data on vaccination status factors. We could not report the actual cause of no vaccination. One of the study’s significant limitations is that most healthcare workers working in these secondary hospitals are Nurses and Midwives, causing unequal selection and increased nurses’ number in the study.
Conclusion
In conclusion, about two-thirds of the HCWs were vaccinated in this study. The complete Hepatitis B vaccination status among health care workers working in two secondary care hospitals of Sindh was good. The percentages of complete Hepatitis B vaccination in Doctors, Laboratory staff, and Allied Health Workers were low even though the employer provided the medical coverage for the Hepatitis B vaccination. The mean knowledge scores among HCWs were low, so the educational interventions should be planned and implemented for increasing the knowledge and awareness related to Hepatitis B and Hepatitis B vaccination among the health care workers. A well-defined vaccination policy for part-time employees should be prioritized to improve the Hepatitis B vaccination coverage. Moreover, factors influencing vaccination status should be identified. Building confidence in the Hepatitis B vaccine’s safety among HCWs and increasing access to the vaccination could improve the rates.
Abbreviations
Authors’ contributions
SS contributed to the design, data collection, analysis, and interpretation of data and drafting the manuscript. RS contributed to the design and interpretation of data, drafting the manuscript, and revised critically the article. IA contributed to data analysis and interpretation of data. MS contributed to the concept, design, and data collection. All authors read and approved the final manuscript.
Ethics approval and consent to participate
Ethical Approval for conducting the study was taken from Ethical Review Committee, Aga Khan University (ERC Reference # 3266). We took consent from participants before they access the questionnaire. Included those participants in the study who voluntarily participated by giving informed consent. We maintained participants’ privacy, autonomy, anonymity, confidentiality, and equity during and after the study.
Acknowledgments
I want to acknowledge the health care workers who took part in this study. I want to thank the Management of Aga Khan Secondary Care Hospitals and Clinical Laboratories Aga Khan University Hospital, Pakistan for providing list of HCWs and support during data collection process. My sincere thanks to Ms. Fatima Khanum, Nurse Manager Aga Khan Secondary Care Hospitals, Pakistan for her extended support from the planning of the study till the completion of the research.
Availability of data and materials
The datasets for this study are available from the corresponding author on reasonable request.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Additional information
Funding
References
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