Prevalence, Molecular Characterization, and Immune Status Response of Hepatitis B Virus Among Healthcare Workers in Yaoundé General Hospital, Cameroon, During May to June 2024: A Hospital‐Based Cross‐Sectional Study

Abstract

ABSTRACT

Background

Hepatitis B virus (HBV) infection is preventable through vaccination. However, healthcare workers (HCWs) are at increased risk of HBV transmission due to occupational exposure.

Aims

This study investigates the prevalence of HBV markers of exposure and infection, HBV genotypes, and immunity among HCWs at Yaoundé General Hospital.

Methods

We conducted a prospective, cross‐sectional study based on self‐administered questionnaires and blood samples collected from HCWs. HBV markers (HBsAg, anti‐HBs, anti‐HBc) and genotypes were analyzed using ELISA MONOLISA kits and hemi‐nested amplification and sequencing focusing on the HBV S region.

Results

Among 173 HCWs, 46.8% (81/173) were exposed (positive for anti‐HBc), 14.8% (12/81) of exposed participants were infected (HBsAg). A 9.8% (17/173) were naturally immunized (positive for anti‐HBc and anti‐HBs) and 60.7% (105/173) had acquired immunity (anti‐HBs only). Phylogenetic analysis revealed the prevalence of only HBV genotype E. Exposure to HBV and current infection was significantly associated with age group, with a significant p < 0.05 (p = 0.0032) predominance in the 20–29 age group 60.1% (104/173) and 32.9% (57/173), respectively. Notably, low vaccine response was closely associated with function, with nurses being at higher risk (OR = 8.52; 95% CI: 3.250–10.567), whereas high vaccine immunity was observed in those who had received all 3 doses of HBV vaccine (OR = 15.861; 95% CI: 0.971–45.591).

Conclusion

This study revealed a significant burden of HBV infection among HCWs in Yaounde General Hospital, Cameroon. Our results highlight the ongoing risk of HBV transmission among HCWs and emphasize the importance of an active, multi‐faced approach, including vaccination programs, precautionary measures, and additional strategies, to effectively contain HBV exposure among HCWs in Cameroon.

Introduction

Hepatitis B virus (HBV) infection is a significant public health problem and a leading cause of liver cancer and liver-related mortality worldwide [1, 2]. HBV is particularly prevalent in sub-Saharan Africa, where HBV is highly endemic with an estimated prevalence of 10%–15% in the general population. According to the World Health Organization (WHO), approximately 2 billion people worldwide are infected with an estimated 240 million chronic carriers, and a significant proportion of whom live in sub-Saharan Africa [2–4].

HBV can be transmitted vertically from mother to her baby during childbirth [2, 5, 6], horizontally by unprotected sexual contact with HBV-infected individuals [2, 7, 8], or parenterally through percutaneous or mucosal exposure to HBV-infected blood and/or body fluids [9, 10], Therefore, groups of people are at increased risk for HBV infection [11–13], including people who have unprotected sex with infected partners, pregnant women with HBV infection, people who share needles or syringes, and healthcare workers (HCWs) [14–17]. Of these, HCWs are at increased risk for HBV infection due to occupational exposure to blood or body fluids while caring for patients, putting them at higher risk for contracting blood-borne viruses. However, vaccination can effectively prevent HBV infection, with protection rates exceeding 96%. To reduce this risk, the WHO recommends that all uninfected HCWs receive the HBV vaccine [17–19].

HBV is a significant public Health concern in Cameroon. In the general population, a national prevalence of 11.2% has been reported in 2017 [20]. Studies have identified HBV prevalence ranges from 5.7% and 7.5% among pregnant women [21]. In adults with a history of surgery, the prevalence is 8.9% [22]; 14.8% among prisoners [23], and 6%–11% among HCWs [24, 25]. Since 2009, the WHO has recommended the HBV birth-dose vaccine, preferably within 24 h [26]. However, in most countries in Africa, the HBV vaccine is part of a pentavalent vaccine and is administered starting at 6–8 weeks of age [27, 28]. In Cameroon, the HBV vaccine has been included in the national immunization program, with the combination vaccine administered to infants at 6, 10, and 14 weeks of age [28]. Although this early vaccination provides essential protection, Cameroon still faces a high burden of HBV infection, with an estimated prevalence rate of 6%–11% among HCWs, and vaccine response rates of 11%–13% [29–31] among HCWs [19, 31–33].

HBV has been classified into ten distinct genotypes, labeled A to J, based on genetic variations within the S-genome region, or across the entire genome [34, 35]. In Cameroon, phylogenetic analysis of HBV strains has revealed a genetic diversity of the virus with a predominance of genotype E (HBV/E) [36–38]. To date, no molecular characterization of HBV among HCWs in Cameroon is available. Understanding the genetic variability of HBV in different regions is essential for designing tailored prevention and control initiatives [39]. The present study aims to investigate the prevalence of markers of HBV exposure, current infection, protection, and genotype among HCWs in Yaoundé General Hospital in the Central Region of Cameroon.

Methodology

Study Design and Setting

This prospective cross-sectional study was conducted at the Yaoundé General Hospital, Cameroon. This hospital is the largest tertiary hospital in the city of Yaoundé, the capital of Cameroon. The hospital provides specialized care to millions of residents and the entire country. It is also one of the country's approved centers for the monitoring and therapeutic management of patients infected with the hepatitis C virus and the HBV. The study was conducted from May 26 to June 30, 2024. More than 90% of the healthcare staff, including nurses, laboratory technicians, doctors, auxiliary staff, cleaners, and medical students or those on rotation in the various care units of the hospital, participated in the study.

Case Definition

The following serologic definitions were used in this study: Exposure to HBV was indicated by the presence of anti-HBc antibodies alone; natural immunity, indicating past or resolved infection, was confirmed by the simultaneous detection of anti-HBc and anti-HBs antibodies; infectious individuals were identified by the presence of HBsAg; and vaccine-induced immunity was characterized by the presence of anti-HBs antibodies alone.

Ethical Statement and Sample Collection

This study was conducted in accordance with the ethical principles of the 1975 Declaration of Helsinki and was approved by the Institutional Ethics Committee of the University of Douala, Cameroon (N°4367/CEI/-UDO/06/2024M). Blood samples were collected from all HCWs who consented to this study. A standardized questionnaire was distributed and administered to all participants to collect sociodemographic data, medical history, and potential risk factors related to HBV infection and immunization. All blood samples collected were aliquoted and stored until analysis.

HBV Serological Tests

The presence of HBsAg, anti-HBc, and anti-HBs serological markers was determined using Monolisa ULTRA and Monolisa PLUS enzyme-linked immunosorbent assay (MONOLISA BIORAD, Marne-La-Coquette, France). The reactivity of samples was determined according to the manufacturer's instructions (MONOLISA BIORAD, Marne-La-Coquette, France). Briefly, a ratio was calculated for each sample by dividing its optical density by the cut-off value. HBV was defined as positive or current infection if HBsAg was detected, HBV exposure was defined as positive if anti-HBc was detected or both anti-HBc and anti-HBs, and natural immunity was described if a patient was found with (positive for anti-HBc and anti-HBs), and acquired immunity if only anti-HBs was detected.

Molecular Analysis

HBV DNA Amplification and Sequencing

HBV DNA was extracted from 200 μL plasma samples using the QIAamp Viral DNA Mini Kit (Qiagen) according to the manufacturer's instructions (QIAGEN QIAamp Viral DNA Mini Kit). The extracted DNA was then subjected to hemi-nested PCR amplification targeting a 783-bp fragment of the S gene, as previously described [40]. Briefly, PCRs were performed using primers (P2f (5′-CCTGCTGGTGGCTCCAGTTC-3′) 979 (5′-CAAAAGACCCACAATTCTTGACATACTTTCCA AT-3′) and Mc2r (5′-GGCAATGATCCCCAACTTCCA-3′) in 25 mL with buffer consisting of 200 nM dNTPs, 200 nM each primer, variable MgCl₂ concentrations, 1 U platinum Taq, and 5 mL template DNA. For the second round of PCR, 2 mL of 1:100 diluted first-round product was used. PCR conditions were as follows 5 min denaturation at 95°C followed by 40 cycles (30 cycles for the second round) of 20 s at 95°C, 20 s annealing at variable temperatures and 90 s extension at 72°C. Sequencing and phylogenetic analysis were performed to determine genotypes as previously described [41]. Cameroonian HBV strains were compared with reference strains from different geographical locations obtained from GenBank. Sequencing was performed using the 3730XL DNA Analyzer (Applied Biosystems). Phylogenetic trees were constructed using the Kimura two-parameter model and the neighbor-joining method in MEGA 12, based on the nucleotide sequences of the amplified gene. The reliability of the phylogenetic tree analysis was confirmed by bootstrap resampling (1000 replicates), and pairwise evolutionary distances were calculated using the Kimura two-parameter model. The nucleotide sequences generated in this study have been deposited in the GenBank database and received accession numbers ranging from PV067257 to PV067267.

Statistical Analysis

Statistical analysis was performed using the International Business Machine (IBM) Statistical Package for Social Sciences (SPSS) software version (V.25.0.). Data were expressed as mean ± standard deviations. Categorical data were expressed as percentages, and continuous data were expressed as median values with first and third interquartile ranges (IQRs). Comparisons between groups were analyzed by Pearson's chi-square test (Pearson's χ²). The odds ratios (ORs) and their 95% confidence interval (95% CI) were calculated to assess the risk of exposure or infection using binary logistic regression. A p-value of less than 0.05 (p < 0.05) was considered statistically significant.

Results

Characteristics of the Study Population

A total of 173 HCWs were included in this study. The mean age of the study population included in this series was 32.84 ± 15.4 years (age range: 19–65 years), and the median age of 31 years (IQR, 26–71 years), with the 20–29 years age group represented 42.2% (73/173) (95% CI: 39.3–45.03). Of these, 68.8% (119/173) were female, 32.9% (57/173) were nurses, and 31.2% (54/173) were medical students or interns. The basic demographic characteristics of the enrolled HCWs are shown in Table 1.

Table 1 Demographic characteristics of the study population and HBV serological markers.

Characteristics	HCWs (N = 173)	Hepatitis B serological markers
Anti-HBc Negative	Anti-HBc Positive	Anti-HBs Negative	Anti-HBs Positive	HBsAg Positive
Sex
Male	54/173 (31.2%)	29/54 (53.7%)	25/54 (46.3%)	17 (31.5%)	37/54 (68.5%)	3/54 (5.6%)
Female	119/173 (68.8)	63/119 (52.9%)	56/119 (47.1%)	34 (28.6%)	85/119 (71.4%)	9/119 (7.56%)
Age (years)
Mean age	32.84 ± 15.4
Median age	31, IQR (26–71)
Age ranges	19–65
< 20	5/173 (2.9%)	3/5 (60%)	2/5 (40%)	3/5 (60%)	2/5 (40%)	1/5 (20%)
20–29	73/173 (42.2%)	24/73 (32.87%)	49/73 (67.1%)	25/63 (32.24%)	48/73 (65.75%)	5/73 (6.84%)
30–39	58/173 (33.5%)	45/58 (77.58%)	15/58 (25.86%)	11/58 (18.96%)	47/58 (81.03%)	2/58 (3.45%)
40–50	24/173 (13.9%)	17/24 (70.8%)	7/24 (29.16%)	8/24 (33.3%)	16/24 (66.7%)	2/24 (8.33%)
≥ 50	13/173 (7.5%)	5/13 (38.46%)	8/13 (61.5%)	4/13 (30.76%)	9/13 (69.2%)	2/13 (15/38%)
Risk factors exposure
Needle injury	89/173 (46.8%)	35/89 (39.32%)	54/89 (60.67%)	21/89 (25.9%)	68/89 (76.4%)	6/89 (6.74%)
Blood transfusion	12/173 (6.9%)	6/12 (50%)	6/12 (50%)	2/12 (16/7%)	10/12 (83.3%)	3/12 (25%)
Conducted surgery	9/173 (5.2%)	7/9 (77.8%)	2/9 (22.22%)	4/9 (44.44%)	5/9 (55.55%)	1/9 (11.1%)
Had a surgical operation	4/173 (2.3%)	3/4 (75%)	1/4 (25%)	1/4 (25%)	3/4 (75%)	1/4 (25%)
Presence of a tattoo or scarification	8/173 (4.6%)	7/8 (87.5%)	1/8 (12.5%)	1/8 (12.5%)	7/8 (87.5%)	1/8 (12.5%)
Absence of exposure	51/173 (29.5%)	34/51 (66.7%)	17/51 (33.3%)	25/51 (49.01%)	26/51 (50.98%)
HCWs specialist
Laboratory technician	29/173 (16.8%)	20/29 (68.9%)	9/29 (31.03%)	10/29 (34.48%)	19/29 (65.51%)	0
Nurses	57/173 (32.9%)	18/57 (31.6%)	39/57 (68.4%)	20/57 (35.08%)	37/57 (64.9%)	7/57 (12.28%)
Intern of medicine	54/173 (31.2%)	36/54 (66.7%)	18/54 (33.3%)	9/54 (16.7%)	45/54 (83.3%)	2/54 (3.7%)
Doctors/physicians	23/173 (13.3%)	15/23 (65.21%)	8/23 (34.8%)	4/23 (17.4%)	19/23 (82.6%)	0
Cleaners	10/173 (5.8%)	3/10 (30%)	7/10 (70%)	9/10 (90%)	2/10 (20%)	3/10 (30%)
Years of service
< 1	47/173 (27.2%)	9/47 (6.38%)	38/47 (80.85%)	22/47 (46.8%)	25/47 (53.19%)	5/47 (10.63%)
1–4	54/173 (31.2%)	28/54 (51.85%)	26/54 (48.14%)	20/54 (37.03%)	34/54 (62.96%)	3/54 (5.55%)
5–9	62/173 (35.8%)	48/62 (77.41%)	14/62 (22.58%)	5/62 (4.88%)	57/62 (91.9%)	2/62 (3.22%)
10–20	7/173 (4.04%)	4/7 (57.14%)	3/7 (42.85%)	3/7 (42.8%)	4/7 (57.14%)	1/7 (14.28%)
> 20	3/173 (1.73%)	3/3 (100%)	0	1/3 (33.3%)	2/3 (66.7%)	1/3 (33.3%)
Hepatitis B vaccine dose reported
0	72/173 (41.6%)	55/72 (76.4%)	17/72 (23.6%)	51/72 (70.8%)	21/72 (29.16%)	7/72 (9.72%)
1	8/173 (7.9%)	3/8 (37.5%)	5/8 (62.5%)	0	8/8 (100%)	2/8 (25%)
2	19/173 (18.8%)	4/19 (21.05%)	15/19 (78.9%)	0	19/19 (100%)	2/19 (10.52)
3	68/173 (67.3%)	68/68 (100%)	40/68 (58.82%)	0	68/68 (100%)	1/68 (1.47%)
More than 3	6/173 (5.9%)	3/6 (50%)	3/6 (50%)	0	6/6 (100%)	0

Distribution of Hepatitis B Serological and Immune Markers

This cross-sectional study included 173 HCWs and showed that 46.8% (81/173) had been exposed to HBV, as indicated by anti-HBc positivity. Notably, 14.8% (12/81) of exposed HCWs were currently infected, testing positive for both anti-HBc and HBsAg (Table 1). A significant correlation between age and HBV exposure/infection was observed, with HCWs aged 20–29 years having higher prevalence rates of 60.1% (104/173) and 41.7% (72/173), respectively (p = 0.034). Nurses and laboratory cleaners had higher rates of HBV exposure, 68.4% (118/173) and 70% (121/173), respectively, and infection, 12.3% (21/173) and 30% (52/173), respectively. Multivariate analysis identified risk factors contributing to HBV infection, including less than 1 year of work experience (2.2-fold increased risk) and accidental exposure to needles, blood, or other fluids (2.4-fold increased risk) (Table 2).

Table 2 Factors contributing to HBV vaccine low response.

Characteristics	HCWs (N = 173)	Unadjusted risk	p value
OR	CI
HCWs specialist
Laboratory technician	29/173 (16.8%)	1.005	0.430–1.930	0,744
Nurses	57/173 (32.9%)	8.520	3.250–10.567	0,000* (p < 0.05)
Intern of medicine	54/173 (31.2%)	1.505	0.250–4.302	0,000* (p < 0.05)
Doctors/physicians	23/173 (13.3%)	3.46	2.250–7.834	0,000* (p < 0.05)
Cleaners	10/173 (5.8%)	1.131	0.012–0.407	0,000* (p < 0.05)
Years of service
< 1	47/173 (27.2%)	2.250	1.215–9.456	0.036* (p < 0.05)
1–4	54/173 (31.2%)	1.459	0.012–0.407	0.042* (p < 0.05)
5–9	62/173 (35.8%)	2.520	0.112–4.407	0.331
10–20	7/173 (4.04%)	1.525	0.740–3.530	0.994
> 20	3/173 (1.73%)	3.122	2.450–7.970	0.567
Hepatitis B vaccine dose reported
0	72/173 (41.6%)	3.702	1.351–11.029	0.037* (p < 0.05)
1	8/173 (7.9%)	5.025	0.554–3.059	0.023* (p < 0.05)
2	19/173 (18.8%)	1.770	0.455–3.059	0.668
3	68/173 (67.3%) 95% CI (52.4–81.6)	15.861	0.971–45.591	0.097
More than 3	6/173 (5.9%)	0.860	0.867–5.837	0.076
Accidental exposure to blood (times)
0	69/173 (39.9%)	4.01	1.601–12.028	0.987
1	7/173 (4.05%)	1.763	2.612–17.603	0.036* (p < 0.05)
2	15/173 (8/67%)	2.403	1.704–23.309	0.023* (p < 0.05)
3	38/173 (21.9%)	2.381	0.976–11.706	0.046* (p < 0.05)
More than 3	44	2.407	1.124–12.076	0.039* (p < 0.05)

Analysis of vaccination status reported showed that 58.4% (101/173) participants had received the HBV vaccine, with the majority, 67.3% (116/173), completing the recommended three-dose schedule. Immunity to HBV infection was demonstrated in 70.5% (122/173) participants, as evidenced by anti-HBs positivity. The distribution of natural and acquired immunity among participants is shown in Table 2. The results indicate that 9.8% (17/173) of the participants had natural immunity (positive for anti-HBc and anti-HBs), while 60.7% (105/173) had acquired immunity through vaccination (only anti-HBs was detected).

Age was a significant factor in natural and acquired immunity (p = 0.0042), with the highest immune response observed in the 30–39 years age group (67/173), 38.5%. Occupational role, work experience, and number of HBV doses also influenced the immune response. Low vaccine response is defined as an inadequate immune response to the HBV vaccine, typically measured by the level of antibodies against the hepatitis B surface antigen (anti-HBs). If antibodies against hepatitis B surface antigen are less than 10 IU/mL after vaccination completion, they are considered to have low immunity. This low vaccine response was closely associated with function, with a higher risk for nurses (OR = 8.52; 95% CI: 3.250–10.567) and physicians/doctors (OR = 3.46; 95% CI: 2.250–7.834), whereas high vaccine immunity was observed in those who had received all three doses of HBV vaccine (OR = 15.861; 95% CI: 0.971–45.591). In addition, work experience of more than 4 years was strongly associated with natural immune response to HBV (p < 0.0001) (Table 2). There was no significant association between sex, category of HCWs, and all serological markers of HBV in the present study.

Molecular Characterization

Phylogenetic analysis of 91.6% (11/12) HCWs with current infection of HBV showed the circulation of only genotype E of HBV (100%) (Figure 1). Of the 11 samples positive in semi-nested amplification, 27.3% (3/11) were cleaners, 63.6% (7/11) were nurses, and 9.1% (1/11) were interns (students in medicine). The difference in distribution between cleaners, nurses, and interns was statistically highly significant (p = 3.5 E−05, OR = 10.5, 95% CI: 2.8–39.5).

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Discussion

HBV is a major cause of chronic hepatitis and hepatocellular carcinoma in Sub-Saharan Africa [42, 43], and HCWs are at risk of HBV infection due to occupational exposure to blood and bodily fluids [17, 18]. Vaccination remains the most effective way to prevent HBV infection [2, 19].

This cross-sectional, hospital-based study investigated the seroepidemiology, immune status, and, for the first time, molecular characterization of HBV infection among Cameroonian HCWs. Our results indicate that 46.8% (81/173) of HCWs were exposed to HBV infection, and 14.8% (12/173) are currently infected. The exposure rate found in the present study is relatively similar to that found among HCWs in health facilities in the Bamenda Health District (47.3%) [31].

Regarding current HBV infection, we found an alarmingly high HBsAg prevalence of 14.8% (12/81) among HCWs who have been exposed, with hospital cleaners and nurses significantly affected at 25% (3/12) and 58.3% (7/12), respectively (p = 0.044). These higher exposure and infection rates can probably be explained by differences in settings and sample size, as well as confirmed frequent contact of HCWs with blood or other body fluids. This alarming prevalence may also be due to limited knowledge or experience of HBV infection among some classes or specialties of HCWs. The high HBsAg prevalence observed in this study is consistent with that reported across regions during a national survey of HBV among HCWs (5.1%–24.0%) [29], or in the health facility in Bamenda (10.6%) [31], and the health facility in Yaoundé (11%) [30], The rate of current HBV infection in the present study is relatively higher than the pooled prevalence of HBV among HCWs in Africa (6.8%) [44], highlighting the continuing risk of HBV transmission in Sub-Saharan Africa. It is well known that HBV infection may occur before occupational exposure, emphasizing the need for timely vaccination [45]. Our findings also highlight the urgent need to implement national comprehensive vaccination initiatives targeting HCWs, including laboratory cleaners and health students, in Cameroon. In addition, an active, multi-faced approach, including vaccination programs, precautionary measures, and additional strategies, is necessary to effectively contain HBV exposure among HCWs in Cameroon.

Our study identified age as a significant factor in both natural and acquired immunity, with the highest immune response observed in the 30–39-year age group. The significant association between age and HBV exposure and/or immunization found in the present study confirms the fact that immune response to vaccination can vary with age, with sustained immune memory and long-term protection of 20–30 years after a complete primary hepatitis B vaccination course during adulthood [46, 47]. Our findings suggest that younger HCWs may be more susceptible to infection, possibly due to inadequate or incomplete vaccination and inexperience or suboptimal adherence to infection control protocols. Our results are similar to previous studies conducted among HCWs in Cameroon [29, 31, 33] and another risk group with HBV in Cameroon, including HIV patients [48], pregnant women [49], and HCC patients [50]. While our study suggests a potential role of childhood immunity among HCWs, we recognized that immunity acquired during infancy may wane over time. Therefore, factors such as natural exposure or booster vaccination may also contribute to the observed immunity among HCWs in the present study. Further studies are needed to investigate the duration of protection conferred by childhood vaccination as well as factors that influence long-term immunity among HCWs in Cameroon.

In Cameroon, the hepatitis B vaccination has been included in the national immunization program and implemented since 2005 [51]. Although the WHO has recommended the HBV birth-dose vaccine [26], the country administered the HBV vaccine to infants at 6, 10, and 14 weeks of age [28]. In addition, vaccinating HCWs is not yet a national strategy in Cameroon, and many HCWs do not take the recommended three HBV vaccine doses. Our results showed that 60.7% of HCWs of all age ranges developed immunity. Our results highlight the importance of HBV vaccination among HCWs in Cameroon and are similar to previous studies conducted in Cameroon [31, 52], Mozambique (60%) [53], and Tanzania (77.1%) [54]. By contrast, countries with mandatory HBV vaccination policies, like Japan, report higher vaccination coverage and immunity rates (93%) [55], This comparison illustrates the potential benefits of implementing comprehensive vaccination strategies and policies for HCWs in Cameroon, emphasizing the need for targeted interventions to improve vaccine uptake and adherence to infection control protocols. In addition, our findings underscore the critical need for comprehensive training, vaccination, and strict adherence to infection control protocols among HCWs and reinforce the central role of vaccination in the prevention of HBV infection [52].

Despite the limited sampling period and sample size tested our results revealed that both natural and acquired immunity were significantly associated with work experience in some specialties, including nurses, physicians and/or doctors, found with a higher risk of low vaccine response, which is concerning given their increased exposure to blood and bodily fluids [1]. Our findings are consistent with previous studies in Cameroon [29, 31, 52]. On the other hand, receiving all 3 doses of the HBV vaccine was strongly associated with high vaccine immunity [1, 2]. These findings reinforce the central role of vaccination in the prevention of HBV infection and highlight the importance of completing the recommended vaccination schedule. In addition, our findings also show that work experience of more than 4 years was strongly associated with natural immune response to HBV is noteworthy. Our findings are consistent with studies conducted in the literature [1, 2] and suggest that HCWs with longer work experience have had more opportunities for exposure to HBV, leading to natural immunity. However, further studies are needed to confirm this association.

This study provides the first comprehensive insight into the prevalence, vaccination status, and genetic diversity of HBV among HCWs in Cameroon. In particular, phylogenetic analysis revealed that HBV genotype E was the only circulating genotype among infected HCWs. This finding is consistent with previous research among blood donors in Cameroon [36] and Central Africa, where genotype E is the predominant HBV genotype [37, 38].

However, our study has several methodological limitations. The cross-sectional design precludes causal inferences between risk factors and HBV infection. In addition, the sample size may not be representative of the broader HCWs population in Yaoundé and Cameroon, and the three pregnant women identified did not consent to participate in the present cross-sectional study. All these may limit the applicability of our results.

Conclusion

This study revealed a significant burden (14.8% current infection) of HBV infection among HCWs in Yaounde General Hospital, Cameroon. Our study highlights the ongoing risk of HBV transmission among HCWs in Cameroon and emphasizes the importance of adequate vaccination, training, and adherence to infection control practices. The results of this study can inform the development of targeted interventions to prevent HBV transmission among HCWs and promote a safer healthcare environment. Promoting HBV management among HCWs could reduce the prevalence of infectious HCWs and consequently the likelihood of nosocomial HBV transmission from HCWs to their patients. A multi-faced approach, including vaccination programs, precautionary measures, and additional strategies, is necessary to effectively contain HBV exposure among HCWs in Cameroon. This study highlights the need for targeted interventions to improve HBV vaccination coverage and immunity among HCWs, particularly in high-risk occupations, and makes it mandatory for all three doses, as well as emphasizes the importance of strengthening vaccination programs and promoting awareness about HBV among HCWs in Cameroon.

Author Contributions

Marie Atsama-Amougou: conceptualization, funding acquisition, methodology, project administration, resources, writing – original draft, writing – review and editing. Fredy Brice Nemg Simo: formal analysis, investigation, methodology, writing – original draft, writing – review and editing. Cedric Fossi Tchinda: software, validation, writing – review and editing. Marie Moukam: methodology, writing – review and editing. Marcel Tongo-Passo: funding acquisition, writing – review and editing. Paul Moundipa-Fewou: project administration, supervision, writing – review and editing.

Acknowledgments

We would like to thank all the staff of Yaounde General Hospital for their participation in this study. All authors have read and approved the final version of the manuscript and declare that the supporting source/financial relationships had no involvement in the study design; collection, analysis, and interpretation of data; writing of the report; or the decision to submit the report for publication. This study has been supported by the corresponding authors.

Conflicts of Interest

The authors declare no conflicts of interest.

Data Availability Statement

The data that support the findings of this study are available within the article.

Transparency Statement

The lead author, Marie Atsama-Amougou, affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

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