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Table of Contents
ORIGINAL ARTICLE
Year : 2022  |  Volume : 21  |  Issue : 4  |  Page : 322-326  

Exposure to patients' sample and prevalence of Hepatitis B and C virus infection among health-care workers in a Nigerian Tertiary Hospital


1 Department of Haematology, College of Medicine and Health Sciences, Afe Babalola University, Ido-Ekiti, Nigeria
2 Department of Internal Medicine, College of Medicine and Health Sciences, Afe Babalola University, Ido-Ekiti, Nigeria
3 Department of Community Medicine, College of Medicine and Health Sciences, Afe Babalola University, Ido-Ekiti, Nigeria
4 Department of Haematology, Federal Teaching Hospital, Ido-Ekiti, Nigeria

Date of Submission20-Feb-2021
Date of Decision10-Jan-2022
Date of Acceptance17-Jun-2022
Date of Web Publication16-Nov-2022

Correspondence Address:
Oluwafemi Johnson Adegbamigbe
Afe Babalola University, Ado-Ekiti, Ekiti
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/aam.aam_44_21

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   Abstract 


Background: Hepatitis B and C lead to chronic disease in hundreds of millions of people and together constitute the most common cause of liver cirrhosis and cancer with attendant mortality. Objective: The objective of this study was to estimate the prevalence of hepatitis B and C virus infection among different categories of health-care workers, looking at the exposure to patients' samples and the prevalence rate among these categories of health workers. This will help to ascertain the risk and the need to pay more attention to preventive measures. Materials and Methods: This was a cross-sectional study conducted over a 2-year period among 217 health-care workers at the department of Haematology of the Federal Teaching Hospital, Ido-Ekiti, Nigeria. Respondents were randomly selected, and blood samples were taken for the hepatitis B and C screening. Data were analyzed using SPSS 20; bivariate analyses were done, and the level of statistical significance was set at P < 0.05. Results: A total of 13 (6.0%) tested positive for HBsAg. Analysis of the marital status of those that tested positive to Hepatitis B, revealed that the highest number (77%) was found among the married, while the singles and the divorced constitute 15.3% and 7.7% respectively. The nurses and nonhealth professionals (admin staff) constitute the highest positive yield of hepatitis B virus (HBV), followed by medical doctors and laboratory staff. The age of the respondent was found to have a statistically significant association with HBV serology (P < 0.05). Conclusion: There is a comparatively lower prevalence of HBsAg among the health-care workers who are directly exposed to patients' samples. The age of the respondent has a significant association with hepatitis B infection.

   Abstract in French 

Résumé
Contexte: L'hépatite B et C conduisent à des maladies chroniques chez des centaines de millions de personnes et constituent ensemble la cause la plus courante de cirrhose du foie et de cancer avec la mortalité des participants. Objectif: L'objectif de cette étude était d'estimer la prévalence de l'infection par le virus de l'hépatite B et du C entre différentes catégories de travailleurs de la santé, en examinant l'exposition aux échantillons des patients et le taux de prévalence entre ces catégories d'agents de santé. Cela aidera à déterminer le risque et la nécessité de prêter plus d'attention aux mesures préventives. Matériel et méthodes: Il s'agissait d'une étude transversale menée sur une période de 2 ans parmi 217 travailleurs de la santé au Département d'hématologie de l'hôpital fédéral universitaire, Ido - Ekiti, au Nigéria. Les répondants ont été sélectionnés au hasard et des échantillons de sang ont été prélevés pour le dépistage de l'hépatite B et du C. Les données ont été analysées à l'aide de SPSS 20; Des analyses bivariées ont été effectuées et le niveau de signification statistique a été fixé à p <0,05. Résultats: Un total de 13 (6,0%) ont été testés positifs pour HBSAG. L'analyse de l'état matrimonial de ceux qui se sont testés positifs à l'hépatite B, ont révélé que le nombre le plus élevé (77%) a été trouvé chez les mariés, tandis que les célibataires et les divorcés constituent respectivement 15,3% et 7,7%. Les infirmières et les professionnels de la santé (personnel administratif) constituent le plus élevé Rendement positif du virus de l'hépatite B (HBV), suivi des médecins et du personnel de laboratoire. L'âge du répondant s'est avéré avoir une association statistiquement significative avec la sérologie du VHB (p <0,05). Conclusion: Il existe une prévalence relativement plus faible de HBSAG chez les travailleurs de la santé qui sont directement exposés aux échantillons des patients. L'âge du répondant a une association significative avec l'infection à l'hépatite B.

Mots-clés: Exposition, hépatite B et C, prévalence

Keywords: Exposure, hepatitis B and C, prevalence


How to cite this article:
Adegbamigbe OJ, Yusuf M, Durowade KA, Oguntoye OO, Ogundare Y. Exposure to patients' sample and prevalence of Hepatitis B and C virus infection among health-care workers in a Nigerian Tertiary Hospital. Ann Afr Med 2022;21:322-6

How to cite this URL:
Adegbamigbe OJ, Yusuf M, Durowade KA, Oguntoye OO, Ogundare Y. Exposure to patients' sample and prevalence of Hepatitis B and C virus infection among health-care workers in a Nigerian Tertiary Hospital. Ann Afr Med [serial online] 2022 [cited 2022 Dec 9];21:322-6. Available from: https://www.annalsafrmed.org/text.asp?2022/21/4/322/361265




   Introduction Top


Viral hepatitis is a systemic infection affecting the liver predominantly.[1] Hepatitis, which is an inflammation of the liver, may occur with limited or no symptoms but often leads to jaundice, anorexia, and malaise. Hepatitis is acute when it lasts >6 months and chronic when it persists longer.[2]

Hepatitis can also be due to the presence of toxic substances or infections caused by protozoan parasites (e.g., Entamoeba histolytica) or viruses. People affected by viral hepatitis usually recover, but some continue to carry the virus for many years and can spread the infection to others. These are chronic carriers. Chronic hepatitis may persist for years and lead eventually to cirrhosis (destruction and replacement of liver cells by fibrous tissue). A substantial number of cirrhotic end up with liver cancer.[2] Chronic carriers serve as an important source of new infections; most have no signs or symptoms and an estimated two-thirds are unaware of their status.[3]

Hepatitis B and C infections can be contracted from unsafe blood, unsafe injections, and sharing drug injection equipment. Children born to mothers with hepatitis and sex partners of people with hepatitis are also at risk of becoming infected. According to the Society for Gastroenterology and Hepatology in Nigeria, hepatitis B virus (HBV) is 50–100 times more infectious than human immunodeficiency virus (HIV) and it is estimated that over two billion people are infected worldwide and approximately one million deaths occur annually from HBV-related illnesses.[3]

Almost all cases of viral hepatitis are caused by one of five viral agents: hepatitis A virus, HBV, hepatitis C virus (HCV), the HBV-associated delta agent or hepatitis D virus, and hepatitis E virus (HEV).[1] The five main hepatitis viruses, referred to as types A, B, C, D, and E, are of greatest concern because of the burden of illness and death they cause and the potential for outbreaks and epidemic spread. In particular, types B and C lead to chronic disease in hundreds of millions of people and, together, are the most common cause of liver cirrhosis and cancer.[4] HBV is a major cause of liver disease morbidity and mortality worldwide, accounting for over 360 million cases of chronic hepatitis and 620,000 deaths per year.[1] It is hyperendemic (i.e., >8% of the population infected) in sub-Saharan Africa and a major cause of chronic liver disease.[5],[6],[7],[8]

As at 2012, the World Health Organization estimated that about 20 million Nigerians have HBV (12.5%). Meaning approximately one in ten of every Nigerians has hepatitis B infection. Hepatitis C is found in about 3% of Nigerians, approximately 1 in about 33 Nigerians.[3] Slightly different prevalence was reported from different regions of the world.[9] Transmission of HBV occurs when blood or body fluid of an infected person enters the body of a person who is not immune.[10] Higher HBsAg prevalence noted among prisoners and rural dwellers was attributed to overcrowding and clustering.[11] Studies from North Central Nigeria indicate that unprotected sex is implicated in the transmission of HBV.[12]

HCV shared a similar mode of transmission with HBV, the most common risk factor for HCV infection in developing countries like Nigeria being transfusion of unscreened blood or plasma-derived products. Other potential risk factors include reusage of syringes and needles, intranasal cocaine use, tattooing, body piercing, accidental needlestick injury, and sharing of household items such as nail clippers, razor blades, and toothbrushes.[13] The estimated risk of transmission of HCV as a result of needlestick injury is 1.8%.[14] Hepatitis B or C can also be seen as coinfection with HIV (HIV/HBV or HIV/HCV). The prevalence of HIV/HBV coinfection was 12.5% and 1.6% for HIV/HCV coinfection in some studies.[15]


   Materials and Methods Top


This study was carried out in the department of hematology and blood transfusion in a Nigerian tertiary hospital situated in Ekiti state with average population of 2.3million.[16],[17]. The hospital is a 290-bedded hospital and has about 3,000 health workers in different professional groups and across different departments. This is a cross-sectional study in which randomly selected health-care workers (HCWs) were tested during the period of this study.

The sample size was calculated to be 75.[18]

Sample size = Z2pq ÷2

However, for a better representation, samples were taken from 217 consenting HCWs.

The professional groups selected were Doctor, Nurse, Laboratory scientist/ Technician, Health assistant, and other non clinical staff, using weighted allocations as derived from the formula : X/Y x calculated sample size. X is the total number of specific professional group in the hospital, Y is the combined total number of all selected professional groups.[19]

X/Y x calculated sample size. Where X is the staff strength of a professional group, Y = Total strength of all professional groups.

Ethical approval from the hospital ethical committee was obtained, and questionnaires were administered.

Four milliliters of blood was collected from the consented HCWs into an ethylenediaminetetraacetic acid-anticoagulated bottle using prominent vein such as the antecubital vein, after maintaining aseptic procedure (by scrubbing the venipuncture site with 70% ethyl alcohol and allowed to dry before introducing the needle for blood withdrawal). The plasma was then separated by centrifugation. This was then carefully withdrawn for testing.

The samples were tested using Micropoint HBsAg Gold Rapid Screen Test Kit,[20] following the standard operating procedure in the manual and also testing control samples along with them. Those that were seronegative were referred for counseling and vaccination, while the seropositive HCWs were referred to the gastroenterology unit for further management.


   Results Top


In this study, 217 samples and questionnaires were analyzed. Of this, those >35 years of age constitute 50.2% while those 35 years and above constituted 49.8% [Table 1]. Of the HCWs in this study, 42.6% are nonclinical hospital staff, nurses constitute 32.5%, doctors 17.7%, medical laboratory scientists and technicians 5.3%, while health assistants constitute 1.9% [Table 1].
Table 1: Sociodemographic characteristics of the respondents (n=217)

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Among the participants, 25.8% (56) are males and 74.2% (161) are females out of total of 217 [Table 1]. A total of 159 (81.1%) were educated above secondary school level, while 41 (18.9%) had primary, Arabic, or secondary school education [Table 1]. Marital status showed that 79.3% of the respondents are married, while 18.4% are single, and 2.3% are either separated, divorced, or widowed [Table 1].

Test result

Hepatitis B and C result

A total of 204 (94%) of the 217 tested were negative while 13 (6%) were positive for hepatitis B infection [Table 2]. All the participants' samples tested for hepatitis C were negative, as shown in [Table 2].
Table 2: Pattern of hepatitis B surface antigen and anti-hepatitis C virus among respondents (n=217)

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As shown in [Table 3], more than three-quarters (77.0%) of those who are positive for HBV are married. Among the professional groups, the nurses had one of the highest percentages of HBV-positive result of 38.5%, as was also found among the nonclinical staff. The doctors constituted 15.3% of the total positive result among the professional groups in the hospital.
Table 3: Distribution of positive hepatitis B virus serology and sociodemographic variables among respondents (n=13)

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In [Table 4], the older age group (≥45 years) had a higher proportion of HBV-seropositive respondents than the younger ones (25–44 years) and this difference was statistically significant (P = 0.009). More than three-quarters of respondents from all the professional groups had negative result; proportionately, the laboratory staff had the highest (8.3%) among those with positive result in all the professional groups. This observed difference was, however, not statistically significant (P = 0.963).
Table 4: Hepatitis B virus serology and sociodemographic variables among respondents

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   Discussion Top


Viral hepatitis is a systemic infection affecting the liver predominantly.[1] It is a known fact that viral hepatitis caused by hepatitis B and C viruses is usually asymptomatic in chronic carriers, and can cause liver cirrhosis and eventually liver cell carcinoma.[2] Due to the nature of transmission through contact with blood, needle pricks from infected persons, HCWs are expected to be at higher risk of contracting these viruses than the general population. In this study, the prevalence rate was found to be 6% [Table 2].[21],[22],[23]

Other studies of HBsAg among HCWs reported the prevalence ranging from 1.5% to 8.1% in Nigeria, Rwanda, and Uganda, which is still less than the 12.3% found in the general population in Nigeria.[23],[24],[25],[26] The seroprevalence of HBsAg in pregnant women was also found to be less than the general populace in Nigeria which was 8.3% according to studies done among 180 pregnant women by Chinenye Gloria et al.[27] Various reasons were given for this difference in HBV seroprevalence among various population groups in Nigeria. One of such reasons attributed to the different values, is the type of screening methods used, as observed in the study done by Musa et al. They noted that HBV prevalence 12.3%, when screening was done using enzyme-linked immunosorbent assay (ELISA). It was 17.5% with screening by immunochromatography, and 13.6% by HBV DNA polymerase chain reaction method.[5],[23]

The National Survey done in Nigeria in 2015 and published in 2016 showed a prevalence rate of 12.3% among 965 participants of general healthy population. This is higher than the 6% prevalence rate found in this study, and the 8.3% found in the study done on pregnant women.[27]

The prevalence of 6% in this study is similar to 5.7% prevalence in the study by Shao et al. among the 442 HCWs who answered the questionnaire.[28]

However, the prevalence of HBV among HCWs of 5.7% from the Shao et al's study was similar to the national prevalence of 6% found among the general population in Tanzania according to the study.[28]

This suggests that the increased risk by HCWs does not equate to increased infection in HCWs as was also found in this study where it was 6% compared to the national value of 12.3%.

It may also suggest that infection through contact with infected blood (on surfaces or needle pricks during surgery) may not significantly increase the risk, as most health workers observe universal precaution in the hospital. This may also be the positive effect of the yearly awareness campaign being done in this hospital on every “World Hepatitis Day.”

Among the various groups, 38.5% of those positive for HBsAg were among nurses, 38.5% from nonclinical/admin staff, while the doctors and laboratory staff constitute 15.3% and 7.7% of the positives, respectively [Table 3]. It is of note that the nonclinical/admin staffs are among those with a high percentage of positives (38.5%), which may suggest that infection through other means may be responsible, other than increased exposure to infected patients' blood samples, as expected among health workers.

In a similar study done in 2003 in this institution, the prevalence was 4.3%; however, majority of the positives were among ward maids (health assistants/attendants) at 50% while the admin staff had the least number of positives at 11%.[29] Although the prevalence had increased over the 15-year interval, there is a reversal, especially with the admin staff, being among those with the highest positivity in this study, unlike the low positivity recorded in the previous study, in spite of the fact that they still constitute the highest proportion of staff (43%) screened in this study, as well as in the previous study where they constitute 38%. There was, however, no difference between the seroprevalence among nurses which still stands at 7.0% in this study [Table 4] and 6.9% in the previous study done in 2003 in this same hospital.[29]

This may be due to increased awareness among frontline health workers to reduce the risk, and the availability of vaccines that had been more embraced by frontline health workers more than the other supportive staff in the hospital.

The married constitute the highest number (77%) of those that tested positive to Hepatitis B, followed by singles and the divorced at 15.3% and 7.7% respectively. This higher value found among the married may be due to the fact that majority of the participants are married, constituting about 79.5% of the participants. This higher value may also suggest that the prevalence in these health workers may be sex related rather than exposure at the place of work. It is also expected that the married who are older in age than the single have had more exposure to hepatitis B infection as found in the study by Shao et al.[28],[30] As shown in [Table 4], the older group (≥45 years) had a higher proportion of HBV-seropositive respondents than the relatively younger ones (25–44 years) with a statistically significant association between age and HBV serology. This might also suggest infection secondary to social, in addition to occupational exposure which expectedly is more common among the older ones.


   Conclusion Top


In this study, the prevalence rate among HCWs was found to be 6%, which is lower than what is found in the general population of 12.3%. It can thus be concluded that increased exposure of health workers does not equate to higher seroprevalence of hepatitis B infection in this study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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