Hepatitis B and C Viral Infection: Prevalence, Knowledge, Attitude, Practice, and Occupational Exposure among Healthcare Workers of Jimma University Medical Center, Southwest Ethiopia
Background. Blood-borne infections have been recognized as an occupational hazard for nearly 50 years. Current treatment for hepatitis B virus (HBV) is very expensive for individuals in developing countries and cannot clear infection after it progresses to the chronic stage. Thus, early screenings of people who are at higher risk like healthcare workers and vaccination and awareness creation on standard precautions (SP) to prevent transmission are mandatory. This study determined seroprevalence of HBV and hepatitis C virus (HCV) among healthcare workers of Jimma University Medical Center (JUMC). Methods. An institution based cross-sectional study was conducted from Nov 2015 to Jan 2016. The lottery method was used to select 240 healthcare workers. Data were collected by a self-administered questionnaire. Five to ten milliliters of whole venous blood was collected from each participant. The blood samples were analyzed (tested) for hepatitis B surface antigen (HBsAg) and anti-HCV antibody using automated Enzyme-Linked Immunosorbent Assay (ELISA). Data were entered into EpiData 3.1 and analyzed by SPSS 23. Results. The positivity of HBsAg was 2.5% (6/240; 95% CI: 0.52-4.48%) and that of anti-HCV antibody was 0.42% (1/240; 95% CI: 0.0-1.23%). Most participants had good knowledge of HBV (73.9%), HCV (60.9%), and SP (82.2%) and positive attitude towards SP (88.7%), but only 42.6% had a good practice of SP. More than half (60%) and nearly half (43%) had a history of ever exposure and exposure in the last one year before the survey, respectively. Females were at lower risk of both having ever exposure (95% CI: (0.241, 0.777)) and exposure in the last one year before the survey (95% CI: (0.297, 0.933)) compared to males. Conclusion. The prevalence of HBV was intermediate according to the endemicity classification by WHO. The practice of SP was poor in most participants and, thus, occupational exposure was high. Therefore, regular screening and vaccination of healthcare workers, regular provision of basic or refresher training and availing logistics, and regular motivation of healthcare workers on the practice of standard precautions are recommended.
In their occupational environment, healthcare workers (HCWs) are exposed to hazardous blood-borne pathogens such as hepatitis B virus (HBV) and hepatitis C virus (HCV). HBV and HCV are common causes of occupational diseases transmitted from patients to HCWs and vice versa and also to HCWs’ families. HBV and HCV infections are serious public health problems that can have consequences in terms of psychological and occupational diseases . HBV is contagious and can easily be transmitted from one infected individual to another by blood contact, from mother to child, by unprotected sexual intercourse, or by sharing of eating utensils and other barber shop and beauty salon equipment. The main transmission routes include prenatal infection, skin and mucous membrane infections caused by contaminated blood or body fluid, sexual contact, and injection drug abuse. In addition, tattooing, ear piercing, acupuncture, dialysis, and even use of a syringe can be the source of infection .
Hepatitis B is a very important public health problem affecting almost 10% of the world population. According to the 2009 WHO report, about 2 billion people are affected with HBV worldwide, more than 350 million suffered from chronic, lifelong infection, and more than one million individuals died because of cirrhosis and liver cancer every year [2–4]. It is also estimated that 170 million are chronically infected with HCV . The burden of HBV infection is highest in the developing world, particularly in Asia and sub-Saharan Africa. WHO estimated that the prevalence of HBV infection in Africa is on average more than 10%. However, a study conducted in Addis Ababa, Ethiopia, showed that the mean prevalence of HBsAg was 6.1% .
The Centers for Disease Control (CDC) reported that 3.9 million individuals (1.8%) are infected with HCV, and 2.7 million of these infections will become chronic . The prevalence of anti-HB virus antibody among volunteer blood donors ranged from 5 to 10%. But the prevalence is higher in persons from lower socioeconomic statuses, people of older age groups, and those persons exposed to blood products . It has been estimated that 14.4% and 1.4% of hospital workers are infected with HBV and HCV, respectively . Healthcare personnel, including support staff, who work in healthcare settings, represent a high-risk population for serious, potentially life-threatening infections such as HIV and HBV. Direct contact with blood and other body fluids is the most common or frequent risk healthcare workers encounter while caring for patients . Studies in the United States have shown that the risk of acquiring HBV after being stuck with a needle from an HBV+ client ranged from 27 to 37%. In addition, the risk of acquiring HCV after being stuck with a needle from an infected person ranged from 3 to 10%. The efficiency for transmission of hepatitis B is high. For example, an accidental splash in the eye of as little as 10−8 ml of infected blood can transmit HBV to a susceptible host .
A safe and effective vaccine against HBV has been available for 20 years and is effective in preventing infection and the serious consequences of hepatitis, including liver cancer and cirrhosis, when given before or after exposure  but there is currently no vaccine for HCV . Hepatitis B vaccine is recommended for pre- and/or postexposure prophylaxis of all persons at risk of contact with blood, blood products, or bodily secretions. Ideally, immunization against hepatitis B should be completed prior to health professional training because the risk of infection is thought to be higher at this time. Immunizing HCWs against hepatitis B prevents nosocomial transmission of the virus from HCWs to patients and from patients to HCWs as it gives long-term protection from hepatitis B infection, possibly lifelong [2, 7]. Since 1990 new hepatitis B infections among children and adolescents have dropped by more than 95% and by 75% in other age groups. However, in Ethiopia, the hepatitis B vaccine for children was introduced into the expanded program for immunization (EPI) program in 2007 . There is not yet routine vaccination of HBV for all adults except for what is being done by some hospitals for their health professionals. There is not also yet postexposure prophylaxis (PEP) for HBV in Ethiopia. The current treatment for hepatitis B virus infection is very expensive for individuals in developing countries like Ethiopia and cannot clear infection after it progresses to a chronic stage . Thus, early screenings of people who are at risk, such as healthcare workers, and the implementation of effective interventions such as vaccination and awareness creation for standard precautions to prevent transmission are mandatory.
Up to date, very few studies have been conducted to determine the seroprevalence of HBV and HCV in different population groups such as blood donors, medical waste handlers, VCT clients, commercial sex workers, and antenatal attendees in Ethiopia. Thus, the aim of this study was to determine the seroprevalence of HBV and HCV among healthcare workers in a specific study area. The study also aimed to assess the knowledge, attitude, practice, and occupational exposure of healthcare workers to guide interventions rendered at prevention and control of HBV and HCV infections in the health facilities.
2. Methods and Materials
2.1. Study Area, Period, and Design
An institution based cross-sectional study was conducted from 11 Nov 2015 to 09 Jan 2016 at Jimma University Medical Center, 350 Kms southwest of Addis Ababa. There were a total of 810 healthcare workers (HCWs) (physicians, dentists, health officers, anesthetists, nurses, midwives, and laboratory personnel/technicians).
2.2.1. Source Population
The source population included all health workers (physicians, dentists, health officers, anesthetists, nurses, midwives, and laboratory technicians) at Jimma University Medical Center who had direct patient care or specimen contact during the study period.
2.2.2. Study Population
The study population included all health workers as described under the source population and those who had direct patient care or specimen contact at least for the last 1 year.
2.3. Sample Size and Sampling Technique
2.3.1. Sample Size
The sample size was calculated using a single population proportion formula assuming 8.7% prevalence (P) of HBV among healthcare workers , 5% level of significance (α), 3% margin of error (d), and 15% nonresponse rate. When corrected using the finite population correction factor (because the size of the source population (N=606) was less than 10,000), the final sample size became 251.
2.3.2. Sampling Technique
The sample size was proportionally allocated to each unit (wards, outpatient departments, and operation rooms). Then, the required number of study participants was selected by the lottery technique from each unit.
(i)Dependent variables(a)Seroprevalence of HBV(b)Seroprevalence of HCV(ii)Independent variables(a)Sociodemographic characteristics(1)Age, sex, religion, ethnicity, marital status, profession, and work experience(b)History of occupational exposure(c)Knowledge of HBV and HCV transmission and prevention(d)Knowledge of standard precautions(e)Attitude towards standard precautions(f)Level of the practice of standard precautions
Knowledge of hepatitis B and C virus was assessed by questions focusing on risk groups and procedures, transmission, treatment, and prevention of hepatitis B and C infection. There were 7 knowledge items for each virus and the total scores ranged from 0 (smallest) to 21 (largest). Knowledge, attitude, and practice of standard precautions were assessed by a set of questions and statements focusing on standard precautions. There were 8 knowledge items and the total scores ranged from 0 (smallest) to 27 (largest). There were 11 attitude statements whose responses were scored on the basis of a Likert scale. The scores ranged from 23 (strongly disagree) to 115 (strongly agree). There were 4 Likert scale questions to assess the frequency of compliance (practice) to standard precautions and the scores ranged from 0 (smallest) to 16 (largest).
Five to ten milliliters of whole venous blood was collected from each participant using a syringe, needle, and organ function test tube. The sample was transported to the JUMC Laboratory by a laboratory professional daily using a cold chain. Serum was separated from cells within an hour of arrival and serum samples were stored at -20 degrees Celsius. The HBsAg and anti-HCV-IgG antibody Enzyme-Linked Immunosorbent Assay (ELISA) was performed according to the manufacturer’s instructions. Samples found positive at initial screening were analyzed again for the second time. Fortunately, all the samples found positive initially were found positive on repeated analysis.
2.6. Data Collection Plan
A self-administered structured English version questionnaire was used to collect data on sociodemographic characteristics, history of occupational exposure, knowledge of hepatitis B or C virus infections, and knowledge, attitude, and practice (KAP) of standard precautions. Data collection from HCWs was facilitated by two staff members (one healthcare worker who was not included in the study and a laboratory professional for blood collection) at each unit.
2.7. Data Analysis
Data were edited, entered into EpiData 3.1, exported to SPSS 20, and cleaned to check for completeness and extreme and missing values. Univariate analyses were performed and presented in tables, charts, and graphs. We could not conduct logistic regression because cases were limited (6 for HBV and 1 for HCV infection) for this purpose.
2.8. Data Quality Assurance
Before starting data collection, the research team thoroughly reviewed the questionnaire. One day orientation was given for facilitators and blood sample collectors to ensure a common understanding of the tool and methods of data collection. The questionnaire was pretested on 10% of the study participants who were not included in the actual study. The validity of the questionnaire was tested by an expert and peer review and the reliability (internal consistency) was checked by Cronbach’s alpha coefficient. During the actual study, collected data were sorted and checked for errors and completeness on site daily. Overall data collection activities were supervised by the principal investigator. The participants anonymously responded to the items on the questionnaire. For laboratory data, specimen quality was checked for hemolysis, transportation conditions (temperature, tubes), and amount. HBsAg and anti-HCV-IgG antibody positive and negative controls were used for ELISA tests.
2.9. Ethical Considerations
The ethical clearance was secured from the College of Health Sciences Institutional Review Board (IRB), Jimma University. A letter of permission was submitted to the Jimma University Medical Center administration body and the administration bodies of each hospital’s unit. The objective of the study was explained to each study participant. The participants were informed that there are interviews and blood sample collection for HBV and HCV screening. Written informed consent for participation was obtained from each study participant. The participation in the study was on a voluntary basis and the participants could withdraw from the study during the interview.
Participants were ensured that all collected data will be used only for the research purpose. Test results were kept confidential by using unique codes given to each study participant. Laboratory personnel had access only to the unique codes written on a sample containing test tubes. The research team members had access to both the unique codes and participants’ identifiers (name and phone number) written in a separate format. All participants were informed of the result and those with a positive result were counseled and linked to care.
2.10. Plan for Data Dissemination
The finding of the study was reported to the Research Coordinating Office of Jimma University. A summary report was also submitted to Jimma University Medical Center.
2.11. Terms and Operational Definitions
(i)Good knowledge or good practice was scored as greater than or equal to 70%(ii)Positive attitude was scored as greater than 69 and negative attitude was scored as less than 69. A score equal to 69 was considered neutral(iii)Good practice was scored as greater than or equal to 60%
3.1. Sociodemographic/Economic Characteristics
A total of 240 participants gave a sample and tested for both HBV and HCV, though 10 participants did not return the questionnaire. However, 11 (4.4%) healthcare workers refused to participate in the study. Most of the refusals (8) were from operation room healthcare workers and the remaining were from the ophthalmology, pediatrics, and psychiatry wards. The majority of participants (120 (52.2%)) were in the age group 25-29 years. The median age of participants was 25 (IQR=24-27) years. The proportion of males and females who participated in the study was almost the same. The leading proportion (102 (44.3%)) of participants was Orthodox Christian and most (137 (59.6%)) were Oromo. The majority of participants (134 (58.3%)) were single and the leading proportion (99 (43%)) was clinical nurses. The majority of participants (121 (52.6%)) had diploma level academic qualification and 148 (64.3%) had work experience of 1-3 years. The median work experience of participants was 3 years (IQR=2-5). A higher percentage (78 (33.9%)) had a monthly salary of 1601-3142 ETB and the mean (SD) of monthly salary was 2598.4 (1119.9) ETB (Table 1).
3.2. Risky Behavior and Medical Procedures
Most participants did not have risky behaviors and medical procedures, except for the injection of drugs where a considerable percentage (89 (38.7%)) of participants had it (Table 2).
3.3. Knowledge of Hepatitis B and C Viruses
3.3.1. Knowledge of Hepatitis B Virus
The reliability (internal consistency) of knowledge items was good (Cronbach’s alpha = 0.712). Most respondents (170 (73.9%)) had good overall knowledge about hepatitis B virus. However, only near to one-third (74 (32.2%)) of the respondents knew that it is not transmitted by contaminated water/food prepared by a person suffering from this infection. Similarly, only less than half (112 (48.7%)) of the respondents knew that HBV infection is treatable and only less than two-thirds (139 (60.5%)) knew that it has postexposure prophylaxis. The details of the responses to each question are indicated (Table 3).
3.3.2. Knowledge of Hepatitis C Virus
The reliability (internal consistency) of knowledge items was good (Cronbach’s alpha = 0.786). A majority of the respondents (140 (60.9%)) had good overall knowledge about hepatitis C virus. However, only a bit greater than one-fifth (52 (22.6%)) and less than one-fifth (34 (14.8%)) of the respondents knew that it is not transmitted by contaminated water/food prepared by a person suffering from this infection and breastfeeding, respectively. Similarly, only a bit greater than one-third (82 (35.7%)) knew that HBV infection is curable and only a bit greater than one-fourth (60 (26.1%)) knew that it has no postexposure prophylaxis. The details of the responses to each question are indicated (Table 4).
3.4. Knowledge, Attitude, and Practice of Standard Precautions
3.4.1. Knowledge of Standard Precautions
The reliability (internal consistency) of knowledge items was good (Cronbach’s alpha = 0.728). Most respondents (189 (82.2%)) had good overall knowledge about standard precautions. However, the level of knowledge in some components of standard precautions was not sufficient. For instance, only near to two-thirds (152 (66.1%)) of the respondents knew that standard precautions apply to blood, all body fluids, secretions, and excretions (except sweat), nonintact skin, or mucous membranes. Similarly, only less than half (103 (44.8%)) knew that standard precautions are intended not only for patients who have signs and symptoms of disease (s). Again, only a bit more than half (134 (58.3%)) of the respondents knew that needles should not be disposed mixed with other wastes/rubbish. The details of the responses to each question are indicated (Table 5).
3.4.2. Attitude towards Standard Precautions
Attitude towards standard precautions was assessed by 23 items. The reliability (internal consistency) of items was good (Cronbach’s alpha = 0.777). Respondents with a score greater than 69 (233) were considered as having a positive attitude and those less than 69 were considered as having a negative attitude. Most of the respondents (88.7%) had a positive attitude towards standard precautions and only 8 (3.5%) were neutral. Positive attitude towards some components of standard precautions was not adequate. To mention just an example, only a bit greater than one-third (82, 35.7%) of the respondents disagree or strongly disagree that contaminated needles should be recapped immediately after use. The details of the responses to each statement are indicated (Table 6).
3.4.3. Practice of Standard Precautions
Only less than half (98 (42.6%)) of the respondents had a good overall practice of standard precautions. Only less than half (94 (40.9%)) of the respondents usually or always practiced standard blood or body fluid precautions in their workplace. Similarly, only less than half (95 (41.3%)) of the respondents usually or always wore personal protective equipment (PPE) when needed. Details of the responses to each item are indicated (Table 7).
3.5. Occupational Exposure
More than half (60%) of the participants reported having ever exposure and 43% reported exposure in the last one year before the survey to blood or body fluid through splashing into the eyes and/or mouth or sharps or needlestick injury. A significant proportion (43%) of the respondents had a history of needlestick injury and the majority (56.6%) of this occurred within one year before the survey. More than one-third (38.3%) of the respondents had a history of sharp injury other than needlestick and the majority (57.95%) of this happened within one year before the survey. Nearly one-third (32.2%) of the respondents had a history of blood or body fluid splash into the eyes and/or mouth and nearly three-fourths (74.3%) of this occurred within one year before the survey (Table 8).
Among sociodemographic characteristics, only sex was associated with occupational exposure of the participants to blood or body fluid through splashing into the eyes and/or mouth or sharps or needlestick injury. Females were more than almost 57% lower at the risk of having ever exposure (AOR = 0.432; 95% CI: (0.241, 0.777)) and more than 42% lower at the risk of being exposed in the last one year before the survey (AOR = 0.527; 95% CI: (0.297, 0.933)) compared to males.
3.6. Prevalence of HBV and HCV Infection
Out of a total of 240 participants, 6 (2.5%; 95% CI: 0.52 to 4.48%) were positive for HBsAg whereas only 1 (0.42%; 95% CI: 0.0 to 1.23%) participant was positive for anti-HCV antibody. There was not any coinfection of HBV and HCV found among the participants. Five of those who were positive for HBsAg were in the age group 20-24 years and one was 48 years old. Five were males; 4 were single and 2 were currently married. Five of them were professional nurses and one was a psychiatry nurse. Five of them were BSc nurses and one was a diploma nurse. Five of them had work experience of 0-2 years and one had work experience of 32 years. All had an adequate overall knowledge of HBV and standard precautions whereas five had adequate knowledge of HCV. Five had a positive attitude towards standard precautions and one was neutral. Four of them had a good practice of standard precautions. Four had a history of ever needlestick injury; two had a history of sharp injury other than needlestick. Two had also a history of blood or body fluid splash into the eyes and/or mouth.
The only positive participant for HCV was a 25-year-old female. She had adequate knowledge of HBV, HCV, and standard precautions. She also had a positive attitude and good practice of standard precautions. She had no history of ever needlestick injury and did not remember the history of blood or body fluid splash into the eyes and/or mouth.
Studies conducted at different areas and on different populations regarding seroprevalence of hepatitis B and C viruses and their associated risk factors have reported different findings. Physicians, dentists, nurses, laboratory staff, and dialysis center personnel are at high risk of acquiring the infection. This study determined the prevalence of HBV and HCV infections among healthcare workers of a tertiary level public hospital.
The prevalence of HBV infection among healthcare workers was 2.5% indicating intermediate endemicity (2-7%) of the problem according to the WHO classification of the prevalence of HBV infection [9, 10] despite high (60%) prevalence of having ever been exposed to blood or body fluid through splashing into the eyes and/or mouth or sharps or needlestick injury. This could be because of lower prevalence of HBV infection in the general community and/or because most healthcare workers had a good overall knowledge of HBV and HCV and standard precautions and positive attitude towards standard precautions contrary to the report of FMOH, Ethiopia .
The prevalence of HBV infection determined in this study was comparable to the prevalence of 4.4% reported among healthcare workers in Khartoum, Sudan , and the prevalence of 2.9% reported among healthcare workers of a tertiary hospital in Rwanda  and the 4.2% prevalence reported among medicine and health science students of Wollo University, Northeast Ethiopia . However, it was lower than the prevalence of 7.3% reported among healthcare workers of Bule Hora Woreda, Southern Ethiopia , the prevalence of 8.7% reported among healthcare workers of the Najran region, Southwestern Saudi Arabia , the prevalence of 8.1% reported among healthcare workers of a tertiary hospital in Uganda , and the prevalence of 7.0% reported among healthcare workers of a tertiary hospital in Tanzania . On the other hand, it was higher than the 1.0% and 0.4% prevalence reported among healthcare workers of a tertiary care hospital in India [17, 18]. This could be because of differences in the level of knowledge of HBV and standard precautions and attitude and practice of standard precautions and occupational exposure.
The prevalence of HCV infection in this study (0.42%) was similar to the 0% prevalence report among healthcare workers of the Najran region, Southwestern Saudi Arabia , the prevalence of 1.3% among healthcare workers of a tertiary hospital in Rwanda , and the prevalence of 0.7% among medicine and health science students of Wollo University, Northeast Ethiopia . This could be because students and healthcare workers might have a similar level of knowledge and practice of standard precautions and, thus, might have similar exposure and infection.
Limitations. This study might underestimate the true prevalence of both HBV and HCV infections as eight healthcare workers working in the operation room refused to participate in the study suspecting that they were already infected and did not want to know their status. The study might also have been underpowered for detecting cases of HCV as the sample size calculated for HBV was used because of resource scarcity. HBsAg positivity indicates either acute (active) or chronic infections. HBsAg negativity also indicates either the true absence of infection (susceptibility) or immunity due to vaccination or immunity due to resolved infection. These statuses can be differentiated by performing HBsAb, HBcAb, and HBcAb IgM tests. However, we did not perform these tests because of resource limitation. We might have also overestimated the practice of standard precautions as it was self-reported (social desirability bias) by the respondents and no attempt was made to directly observe actual practice. The same was true for the history of occupational exposure which was also self-reported (recall bias) by the respondents and no attempt was made to revise their health records.
This study has determined the prevalence of HBV and HCV infections among healthcare workers and found intermediate endemicity of HBV infection and nonnegligible prevalence of HCV. The practice of standard precautions was also poor in most participants and, thus, occupational exposure was high. Thus, we recommended that JUMC regularly screen healthcare workers and avail vaccine which was started soon after completion of this study and interrupted later. We also recommend that JUMC and other interested stakeholders regularly provide basic or refresher training for healthcare workers on blood-borne infections and their effective prevention methods (standard precautions). JUMC should also avail logistics and regularly motivate healthcare workers on the practice of standard precautions.
|AOR:||Adjusted odds ratio|
|ELISA:||Enzyme-Linked Immunosorbent Assay|
|FMOH:||Federal Ministry of Health|
|HBsAg:||Hepatitis B surface antigen|
|HBV:||Hepatitis B virus|
|HCV:||Hepatitis B virus|
|HIV:||Human Immunodeficiency Virus|
|JUMC:||Jimma University Medical Center|
|KAP:||Knowledge, attitude, and practice|
|VCT:||Voluntary counseling and testing.|
All relevant data are within the manuscript.
Conflicts of Interest
The authors declare that there are no conflicts of interest.
Habtemu J. Hebo, Desta H. Gemeda, and Kedir A. Abdusemed conceptualized the study. Habtemu J. Hebo, Desta H. Gemeda, and Kedir A. Abdusemed designed the methods. Habtemu J. Hebo, Desta H. Gemeda, and Kedir A. Abdusemed acquired the funding. Habtemu J. Hebo and Kedir A. Abdusemed curated the data. Habtemu J. Hebo conducted formal analysis. Habtemu J. Hebo and Desta H. Gemeda wrote the report. Habtemu J. Hebo prepared the draft manuscript.
This research was funded by the Institute of Health, Jimma University, as part of the academic staff mega project research. We would like to extend our gratitude to Jimma University for funding this study. We are also grateful to the participants of this study and the data collectors including laboratory personnel.
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