|
 
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| ORIGINAL ARTICLE |
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| Year : 2022 | Volume
: 29
| Issue : 2 | Page : 75-81 |
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Hepatitis B and C seroprevalence among residents in Lagos State, Nigeria: A population-based survey
Oluwakemi O Odukoya1, Kofoworola A Odeyemi1, Oladoyin M Odubanjo2, Brenda C Isikekpei3, Ugonnaya U Igwilo3, Yahaya M Disu4, Alero Ann Roberts1, Tolulope F Olufunlayo1, Yetunde Kuyinu5, Nasir Ariyibi3, Ugochukwu T Eze3, Tayo Awoyale3, Olanrewaju Ikpeekha3, Olumuyiwa O Odusanya5, Adebayo Temitayo Onajole1
1 Department of Community Health and Primary Care, College of Medicine, University of Lagos; Department of Community Health, Lagos University Teaching Hospital, Lagos, Nigeria
2 The Nigerian Academy of Science, Lagos, Nigeria
3 Department of Community Health, Lagos University Teaching Hospital, Lagos, Nigeria
4 Nigeria Centre for Disease Control, Abuja, Nigeria
5 Department of Community Health, College of Medicine, Lagos State University, Teaching Hospital, Lagos, Nigeria
| Date of Submission | 15-Dec-2021 |
| Date of Decision | 16-Jan-2022 |
| Date of Acceptance | 27-Jan-2022 |
| Date of Web Publication | 23-Apr-2022 |
Correspondence Address:
Oluwakemi O Odukoya
Department of Community Health and Primary Care, College of Medicine, University of Lagos, PMB 12003, Surulere, Lagos
Nigeria
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/npmj.npmj_776_21
Background: Hepatitis is one of the leading causes of morbidity and mortality, particularly in developing countries. It is often caused by hepatitis B and C, which are both preventable and treatable. Available information on Hepatitis B and C in Nigeria is based primarily on estimates obtained from specific population sub-groups or hospital-based surveys leaving gaps in population-level knowledge, attitudes, and prevalence. This study aimed to assess the knowledge, attitude and associated factors of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections amongst residents of Lagos State. Methodology: This was a community-based descriptive cross-sectional study carried out in all the 20 local government areas of Lagos state using a multistage sampling technique. Data were collected using pre-tested interviewer-administered questionnaires. Blood samples were taken (pinprick) from respondents (n = 4862) and tested using hepatitis B and C surface antigen tests after obtaining informed consent. Results: The overall prevalence of HBV infection in Lagos State was 2.1% while the prevalence of HCV infection was 0.1%. Only about half of all the respondents (50.9%) had heard about hepatitis B before the survey. Knowledge of the specific symptoms of HBV was also very low. For instance, only 28.1% of the respondents knew that yellowness of the eyes is associated with hepatitis while < 1% (0.1%) knew that HBV infection is associated with the passage of yellow urine. The most common source of information about hepatitis was the radio (13.0%). Only 36.2% of the respondents knew that HBV infection could be prevented. Overall, 28.8% of the respondents were aware of the hepatitis B vaccine. Less than half (40.9%) felt it was necessary to get vaccinated against HBV, however, a similar proportion (41.9%) would want to be vaccinated against HBV. Only 2.5% of all the respondents had ever received HBV vaccines while 3.5% had ever been tested for hepatitis B before this survey. There was a statistically significant association between HBV infection and respondents' use of shared clippers and work exposure involving contact with body parts and body fluids (P < 0.05). Conclusion: The knowledge, awareness and risk perception of HBV infection were low, however, almost half of the residents were willing to receive hepatitis B vaccinations if offered. It is recommended that the population-based prevention programmes and regular community-based surveillance be conducted by the public health department of Lagos State Ministry of Health. In addition, the strengthening of routine immunisation and vaccination of high-risk groups should be prioritised.
Keywords: Hepatitis B, hepatitis C, Nigeria, population-based survey, seroprevalence
How to cite this article:
Odukoya OO, Odeyemi KA, Odubanjo OM, Isikekpei BC, Igwilo UU, Disu YM, Roberts AA, Olufunlayo TF, Kuyinu Y, Ariyibi N, Eze UT, Awoyale T, Ikpeekha O, Odusanya OO, Onajole AT. Hepatitis B and C seroprevalence among residents in Lagos State, Nigeria: A population-based survey. Niger Postgrad Med J 2022;29:75-81 |
How to cite this URL:
Odukoya OO, Odeyemi KA, Odubanjo OM, Isikekpei BC, Igwilo UU, Disu YM, Roberts AA, Olufunlayo TF, Kuyinu Y, Ariyibi N, Eze UT, Awoyale T, Ikpeekha O, Odusanya OO, Onajole AT. Hepatitis B and C seroprevalence among residents in Lagos State, Nigeria: A population-based survey. Niger Postgrad Med J [serial online] 2022 [cited 2023 Mar 24];29:75-81. Available from: https://www.npmj.org/text.asp?2022/29/2/75/343741 |
| Introduction | |  |
Globally 325 million people are living with hepatitis B virus (HBV) or hepatitis C virus (HCV) infections.[1] In 2015, HBV caused an estimated 887,000 deaths mainly from complications such as cirrhosis and hepatocellular carcinoma while 257 million people were living with the chronic infectious disease.[2] Also globally, about 71 million people are living with chronic hepatitis C infection causing about 400,000 deaths in 2016.[3] The World Health Organization (WHO) African region is among the regions with the highest prevalence of HBV infection, where 6.1% of the adult population live with the HBV.[2]
According to the WHO, the prevalence of HBV infection is classified as high (>8.0%), intermediate (2%–8%) and low (<2%).[4] In Nigeria, 19 million people are estimated to be living with HBV infection with an average prevalence rate reported to range from 11% to 13%.[3],[5],[6],[7] Also for HCV infection in Nigeria, about 3.2 million people are estimated to live with the infection with a prevalence rate of 2.1%.[8]
Hepatitis is a major public health problem in Nigeria and a highly infectious disease as infected individuals may often be unaware and unable to take preventive measures to reduce transmission. One of the key global health sector strategies towards eliminating hepatitis is information for focused action. Therefore, an effective Nigerian response to the hepatitis B and C (HBV and HCV) pandemic requires data on the current burden and epidemiology of the viral hepatitis.
HBV infection is a life-threatening infection, and 20%–30% of adults with the chronic infection will develop cirrhosis and liver cancer.[2] Notwithstanding, there is an available and safe effective hepatitis B vaccine that confers 98%–100% protection.[2] In addition, chronic HCV infection increases the risk of cirrhosis by 15%–20% within 20 years and is a major cause of liver cancer.[3] However, more than 95% of those infected achieve full recovery with antiviral therapy.[3] Lack of access to testing, vaccination, treatment and sociocultural factors serve as barriers in developing countries and play a major role in increasing the burden of HBV and HCV infections.[3],[4],[5],[6],[7],[8]
HBV and HCV infections have social and economic implications such as stigmatisation leading to marginalisation of those infected. This can have significant psychological, emotional impact and reduce their employability, economic opportunities as well their ability to develop intimate relationships and social interactions. It also poses financial burden on the individual and their family because of the regular monitoring that is required for its management.[9],[10] In spite of the high infectivity of HBV and HCV infections, these are both preventable and manageable with good outcomes. However, for interventions to be effective and scarce resources efficiently utilised, there must be scientific evidence guiding implementation of such interventions. Much of the available information on HBV and HCV infection prevalence were based on estimates from hospital-based surveys or surveys conducted amongst specific high-risk sub-population groups.[3],[8] Population-based information on the prevalence of HBV and HCV infections in Nigeria is currently scarce.
This study set out to assess the awareness and knowledge of hepatitis, their attitudes and risk perception and to determine the seroprevalence of HBV and HCV and identify factors that may be responsible for their transmissions amongst residents of Lagos State.
| Methodology | | |
This study was conducted in Lagos State, the commercial hub of Nigeria and one of the most populous states in the country. The state has an estimated population of 21 million inhabitants according to Lagos State Bureau of Statistics; however, the 2006 census gives a figure of 9,013,534 inhabitants. The annual growth rate in Lagos State is 3.22% and its population density is 4139 persons per sq. kilometres. Lagos State is divided into 20 local government areas (LGA) in line with the nation's three-tier federal structure.
This was a community-based descriptive cross-sectional study involving households in all the 20 LGAs in Lagos State. Considering a confidence level of 95%, an alpha of 0.05, a precision of 5% and an expected non-response rate of 10%, the sample size estimated for each LGA was 240, making a total of 4800.
A multistage sampling technique was used. One ward was selected in each LGA by simple random sampling. A list of streets or clusters in that ward was obtained from the LGA secretariat. Twenty streets or clusters were randomly selected from this list and 12 houses were chosen from each selected street/cluster using a systematic sampling method. One household was randomly selected from each selected house and one eligible respondent from each selected household was then chosen by simple random sampling and included in the study after informed consent was given. Eligible respondents had to be apparently healthy and aged 18 years and above.
Data were collected in each LGA by a team consisting of one supervisor (minimum of MBBS degree), four trained data collectors and one laboratory technologist. Data were collected using pre-tested interviewer-administered questionnaires and blood samples (pinprick) for testing were taken by the laboratory technologist using the HBV and HCV test kits. The questionnaire consists of five sections labelled A to E. Section A: Sociodemographic and work details (Q # 1–22); Section B: Knowledge of HBV and HCV (Q # 23–33); Section C: Attitude towards risk of HBV or HCV (Q # 34–37); Section D: Factors associated with the knowledge, attitude and seroprevalence of HBV and HCV infections (Q # 38–48); and Section E: Test results for HBV and HCV.
Hepatitis B virus and hepatitis C virus testing
The skin over the tip of the middle or ring finger of the respondent was punctured with a sterile lancet to obtain hanging drops of finger stick whole blood after it was cleaned with alcohol swab. The hanging drops of finger stick whole blood were allowed to fall onto the “specimen pad” of the hepatitis B surface antigen and HCV rapid test strips (Abon Biopharm [Hangzhou] Co. Ltd., P. R., China). Then, a drop of buffer solution was added. The result was read at 15 min according to the manufacturer's instructions. A strip with two distinct coloured lines was read as positive while with a single-coloured line appearing at the control region was read as negative. The rapid test strips have sensitivity of 99.0% (98.1%–99.6%) and specificity of 99.1% (98.5%–99.5%). Study participants that were positive for HBV or HCV infection were duly counselled and subsequently referred to a gastroenterologist at a designated teaching hospital for further assessment and possible treatment.
Those found negative were counselled on the importance of vaccination. Data were collected over a 6-week period between January and February 2014. Ethical clearance was obtained from the Ethical Review Committee of Lagos State University Teaching Hospital.
The data were entered using Epi Info and analysed using IBM Statistical Product and Service Solutions version 17.0 (SPSS Inc., Chicago, IL, USA) and presented using frequency tables. Continuous variable such as age of respondents was summarised using median and interquartile range (IQR). Alpha was set at 0.05; Pearson's Chi-square was used to test for associations between some key variables and HBV infection status. Values of P < 0.05 were considered statistically significant. Logistic regression was done to identify predictors of a positive HBV infection status.
| Results | | |
Sociodemographic characteristics of respondents
In [Table 1], majority of the respondents are in the age group of 31–40 (27.9%) with a median age and IQR of 38 (30–50) years. Furthermore, majority are females (58.9%), married (72.7%), with secondary education (47.4%), Christians (59.2%) and Yoruba ethnic group (72.3%).
Hepatitis B virus and hepatitis C virus infection prevalence
[Table 2] shows that the prevalence of HBV infection in Lagos State was 2.1% (95% confidence interval [CI]: 1.6–2.8) but ranged from 0.0 to 6.0 across the different LGAs. HBV infection prevalence was highest in Badagry (6.0%), followed by Ikorodu (5.0%). There was no HBV infection detected in Somolu LGA. The prevalence of HCV infection in the state was 0.1% but ranged from 0.0 to 0.4 across the different LGAs. Seventeen LGAs recorded no HCV infection while 3 LGAs recorded a prevalence of 0.4% each. | Table 2: Hepatitis B virus and hepatitis C virus prevalence by local Government area (n=4862)
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Respondents' awareness of hepatitis prior to the survey
More than half (51.1%) of the respondents were aware of hepatitis prior to the survey. The most common source of their awareness was through radio (13.0%), followed by health workers (12.6%), friends and relative (11.8%) and television (9.4%).
Respondents' knowledge of mode of transmission and common symptoms of hepatitis
From [Table 3], about one-third (32.1%) of the respondents knew that blood transfusion was a mode of transmission, followed by sharing of sharp objects (29.4%), while 9.5% of them said they knew transmission can be from mother to child.
On knowledge of common symptoms of HBV and HCV infections, yellowness of the eyes, recurrent fever and general feeling of being unwell were correctly identified by 22%, 16.4% and 16.2% of the respondents, respectively. Over one-third (36.2%) knew that HBV and HCV infections are preventable, 28.8% knew that there is a vaccine for HBV, while 3 out of 10 knew that it can be cured. | Table 3: Knowledge of hepatitis B virus and hepatitis C virus infections amongst respondents
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Attitude towards hepatitis B virus infection
[Table 4] shows that about 1 in 4 of the respondents get worried when they get cuts from unsterilised sharp objects. Furthermore, 41% felt it was necessary to get vaccinated while about 42% would want to get vaccinated. Prior to the survey, only 3.5% and 2.5% of the respondents had been tested and vaccinated, respectively.
Characteristics of hepatitis B virus-positive persons
One hundred respondents tested positive to HBV out of 4862 giving a prevalence rate of 2.1%. Majority of them were within 21 and 30 years with a median age of 33 (IQR: 25–42 years), males (55.0%), secondary education (48.0%), married (65.0%) and had jobs with contact with human sweat. More so, a good proportion had jobs that involve contact with body fluids (20.0%) as well human saliva (19.0%).
Job characteristics of hepatitis B virus-positive persons
[Table 5] shows that more than four-fifth (81%) of those who were infected with HBV worked in settings that exposed them to different kinds of body fluids. | Table 5: Job characteristics of hepatitis B virus-positive persons (n=100)
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Factors associated with hepatitis B virus infection
From [Table 6], there was a statistically significant association between clipper sharing (P = 0.001), job exposures to body fluids (P = 0.011), to sweat (P = 0.006), to human body parts (P = 0.047) and HBV infection. However, no statistically significant association was established with other forms of behaviour/lifestyle and job exposure listed.
Logistic regression of independent variables with hepatitis B virus status
From [Table 7], amongst other factors, only clipper sharing was significantly associated with being HBV positive with P = 0.002 at 95% CI. The results further showed that those who shared clipper (9%), contact with human body fluids (30%), contact with human body parts (26.5%) and contact with human sweat (41.1%) have more odds of being infected with HBV compared to those who did not. | Table 7: Logistic regression of independent variables with hepatitis B virus status
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| Discussion | | |
We report a HBV and HCV seroprevalence of 2.1% and 0.1%, respectively. While these figures may appear low, there are concerns because it is occurring in a densely populated state like Lagos with about 21 million residents. A similar study carried out in a specialist referral hospital setting in Ondo State in South-western Nigeria amongst 209 healthcare workers revealed a higher seroprevalence of 6.7% and 8.1% for the hepatitis B surface antigen and the hepatitis C, respectively.[11] The higher prevalence in that study in comparison to ours may be as a result an increased risk for HBV infection common amongst healthcare workers.
In this study, the low prevalence of knowledge specific to the symptomatology and prevention of HBV and HCV infections were similar to that of a community-based study conducted amongst 600 residents from two selected districts in India.[12] We observed that more than half (51.1%) of the respondents were aware of HBV and HCV infections, however, this did not correlate with their knowledge which was quite low in this study. This finding is different from another study conducted amongst 758 private and public university students in Lagos, Ogun and Abia States in Nigeria, where less than half of the respondents were aware, but the mean knowledge score was high.[13] Furthermore, studies conducted amongst healthcare workers at a federal hospital in Ile-Ife, South-western Nigeria, and Bida, North-central Nigeria, showed a significantly high level of awareness and knowledge which may be linked to their occupation and exposure to health-related information.[14],[15] The possible explanation for the high level of awareness and low level of knowledge in our study may be due to lack of exposure to detailed information about the disease in this population which is often not the case in occupations such as healthcare where the risk of exposure is high.
In this study, the most identified source of awareness was through the radio, which may have been inadequate to provide specific knowledge of HBV and HCV infections. This low level of knowledge may lead to an obscure propagation of the disease in the population. It is, therefore, vital to ensure tailored health education and risk communication interventions for the general population and specific groups such as health workers to bridge this gap.
The study showed that 41% of the respondents believed that receiving hepatitis B vaccine was necessary and 42% of them also said they are willing to get vaccinated. It showed that 3.5% of the respondents have been tested for HBV and HCV while 2.5% of them have received the vaccine. This was in contrast to the community-based study conducted amongst university students in Lagos, Ogun and Abia States, where 21% of the university students had received a dose of hepatitis B vaccine.[13] A facility-based study conducted amongst healthcare workers of a federal teaching hospital in Ile-Ife, Osun State, Nigeria, reported even higher figures where 65% of the health workers had received a dose of hepatitis B vaccine.[15] The vaccination rate (2.5%) in this study was significantly lower than the recommended rate of 80%, and this calls for urgent interventions to promote the uptake of hepatitis B vaccine amongst the populace.[16] This discrepancy between willingness to get the vaccine and the prevalence of those who had received the vaccine may signal the presence of existing barriers to getting vaccinated. Future studies should focus on identifying the barriers to HBV vaccination amongst the residents of the state in a bid to bridge the existing gaps between vaccination willingness, access and uptake.
Furthermore, this study showed that HBV infection was associated with the risky behaviour of clipper sharing, scarifications and occupations that had a high risk of exposure to body fluids and human body parts. A study in Singapore reported that sharing of household items increased the risk of HBV infection.[17] More specifically, a study conducted in Malaysia and Northern Brazil revealed that the most common risk behaviours related to hepatitis B were sharing of nail cutters, body piercings and those undergoing acupuncture.[18],[19] However, another study conducted in Egypt found no evidence of sharing nail cutters being a substantial means of HBV transmission.[20] Furthermore, 81% of the respondents who were infected with hepatitis B worked in settings that exposed them to body fluids. This finding is consistent with the high seroprevalence observed in a similar study amongst 209 healthcare workers in a specialist hospital setting in Ondo, a south-western state, in Nigeria.[11] The implication of the findings of this study is that population-level screening for viral hepatitis and subsequent vaccinations are low in the population, therefore, expanded screening and vaccination programmes in government hospitals should be targeted at high-risk groups.
The main strength of this study was the large sample size used to determine population-based estimates of HBV and HCV seroprevalence in Lagos State. It provides useful data to guide policy and targeted interventions, which is vital for the public health response required to eliminate the scourge of viral hepatitis. One limitation of our study was that we were unable to identify the correlates of HCV because the number of positive persons was very low. Furthermore, our findings, though relevant for Lagos State, may not be generalisable to other states in Nigeria due to differences in the sociocultural practices, risk factors and other characteristics across states.
[TAG:2]Conclusion [/TAG:2]
The study found that the overall prevalence of HBV and HCV infections was 2.1% and 0.1%, respectively. Half of all the respondents (50.9%) were aware of HBV and HCV infections; about one-third of them (32.1%) knew that blood transfusion was a mode of transmission, but the knowledge of specific symptoms of HBV was very low. While 28.8% of the respondents were aware of the hepatitis B vaccine, less than half (40.9%) felt it was necessary to get vaccinated and 41.9% of the respondents were willing to be vaccinated. The prevalence of hepatitis B testing and vaccination was very low at 3.5% and 2.5%, respectively. Sharing of clippers and exposure to body fluids were significantly associated with HBV infection. Our findings emphasise the need for continued hepatitis surveillance and population-based educational campaigns for the prevention of viral hepatitis. A key recommendation to the Lagos State Ministry of Health would be to develop, scale up and integrate viral hepatitis prevention interventions into existing health programmes to improve screening, vaccinations and treatment of hepatitis B and C. Population-based prevention programmes should also be considered.
Acknowledgements
This study was funded by the Lagos State Ministry of Health and conducted by the Association of Public Health Physicians of Nigeria, Lagos branch. We are thankful to all the participants and the community members who facilitated the conduct of this study.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]
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