Hepatitis B virus (HBV) infection remains a major global public health problem, affecting millions worldwide and causing chronic liver disease, cirrhosis, and hepatocellular carcinoma [10]. HBV is primarily transmitted via blood, sexual contact, and perinatal routes. Despite vaccination programs, HBV continues to pose challenges in low- and middle-income countries [10].

Blood transfusion, though life-saving, is a potential route for HBV transmission, particularly as many infected individuals remain asymptomatic during early infection. Consequently, blood donors serve as a sentinel population for monitoring HBV prevalence and evaluating donor screening efficacy [1].

In India, HBV prevalence among donors varies regionally, ranging from 0.91% to 2.5% [1–4]. Male donors and replacement donors generally exhibit higher seropositivity, while young adults (18–35 years) often represent the most affected age group [3–6]. Screening in India follows NACO and WHO guidelines, primarily using HBsAg assays (ELISA/CLIA). While effective, these tests may miss infections in the window period or occult cases, and advanced NAT testing is not universally available [7–9].

Hassan Institute of Medical Sciences (HIMS), Hassan, a tertiary care center, handles approximately 12,647 blood donations annually, yet local data on HBV prevalence is limited. Understanding seroprevalence in this population is vital to guide blood safety policies, donor recruitment strategies, and public health interventions.

This study aimed to determine the seroprevalence of HBV among voluntary and replacement blood donors at HIMS, Hassan, and analyze associations with age, gender, and donor type to inform effective transfusion safety and vaccination strategies.

METHODS AND METHODOLOGY

Study Design

This was a retrospective cross-sectional study conducted at the blood bank of Hassan Institute of Medical Sciences (HIMS), Hassan, to determine the seroprevalence of Hepatitis B virus infection among blood donors.

Study Period

The study reviewed records of all blood donors from August 2024 to July 2025

Study Population

The study included all voluntary and replacement blood donors who met the eligibility criteria outlined by WHO and NACO (National AIDS Control Organisation) guidelines. Donors deferred due to medical conditions, recent infections, high-risk behaviors, or other contraindications were excluded.

The total number of donors during the study period was 12,647.

Sample Size

As this was a retrospective study, the sample size consisted of all eligible donors during the study period, in accordance with WHO and NACO guidelines. Therefore, no separate sample size calculation was required.

Data Collection

Demographic and laboratory data were extracted from blood bank records using a structured data collection proforma. Variables collected included:

• Age
• Gender
• Donor type (voluntary or replacement)
• HBsAg test results

Screening and Testing

All donors had been screened for Hepatitis B surface antigen (HBsAg) using enzyme-linked immunosorbent assay (ELISA) or chemiluminescence immunoassay (CLIA) kits approved by national regulatory authorities. Samples that tested positive were re-tested for confirmation as per standard blood bank protocols.

Data Analysis

Data were entered into Microsoft Excel and analyzed using SPSS version 25.0.

• Descriptive statistics: Used to calculate the frequency and percentage of HBsAg positivity.
• Inferential statistics: Chi-square test was used to assess associations between HBV seropositivity and demographic variables (age, gender, donor type).
• A p-value <0.05 was considered statistically significant.

Ethical Considerations

The study protocol was approved by the Institutional Ethics Committee of HIMS, Hassan.

• Since the study was retrospective, no direct consent from donors was required.
• Confidentiality of donor information was strictly maintained, and all data were anonymized for analysis.

RESULTS

Table 1. Demographic Distribution of Donors (n = 12,647)

Table 2. Overall Seroprevalence of HBsAg

Table 3. Seroprevalence by Gender

Table 4. Seroprevalence by Age Group

Table 5. Seroprevalence by Donor Type

DISCUSSION

This study demonstrates an HBsAg seroprevalence of 1.20% among blood donors at HIMS, Hassan, which is consistent with previously reported prevalence in India (0.91%–1.6%) [1–6]. These findings indicate that HBV infection continues to circulate in the population, though the trend appears to be declining due to vaccination and improved screening practices.

Gender-wise analysis showed higher seropositivity in males (1.28%) compared to females (0.87%), in line with previous studies from North and Central India [3,4]. This may be attributed to a larger proportion of male donors, higher occupational exposure, and behavioral risk factors. Female donors are fewer in number and often demonstrate lower risk profiles.

Age distribution indicated that donors aged 26–35 years had the highest prevalence (1.53%), corroborating findings of Raina et al. and Kaur et al. [5,6]. Young adults may have higher exposure risks due to lifestyle and occupational factors, while the lower prevalence in older age groups might reflect cumulative immunity from vaccination or natural infection.

Donor type analysis revealed slightly higher seroprevalence in replacement donors (1.47%) compared to voluntary donors (0.98%). Replacement donors often come from family/friend networks and may underreport risk factors, whereas voluntary donors are typically pre-screened and educated about eligibility, as observed in other Indian studies [1,2]. This underscores the importance of promoting voluntary blood donation to enhance transfusion safety.

Despite routine screening, the persistence of HBsAg-positive donors highlights the residual risk of transfusion-transmitted HBV. Screening using ELISA/CLIA remains effective but may miss cases in the window period or occult infections [7–9]. Incorporation of NAT testing could further reduce this risk but remains limited by cost and infrastructure.

The study findings reinforce the importance of continuous surveillance, strengthening donor education, improving vaccination coverage, and employing highly sensitive screening techniques. Regional data like this also assists policymakers in prioritizing high-risk populations for preventive interventions.

Comparisons with other Indian studies show similar prevalence trends: Sharma et al. reported 1.1% HBsAg positivity in North India [1]; Singh et al. observed 1.3% in Central India [2]; Reddy et al. reported 1.2% in Hyderabad [5]. The findings from HIMS, Hassan, are thus consistent with the broader Indian context, reflecting effective but ongoing challenges in HBV control.

CONCLUSION

The HBsAg seroprevalence among blood donors at HIMS Hassan is 1.20%, with higher rates in males, young adults, and replacement donors.

Despite stringent screening, HBV-positive donors pose a continued risk for transfusion-transmitted infections.

Limitations: Retrospective design, single-center data, testing limited to HBsAg without NAT confirmation or assessment of occult infections.

Future Directions:

• Multicentric studies to assess broader regional prevalence
• Incorporation of NAT and advanced screening for early detection
• Enhanced public awareness, vaccination campaigns, and promotion of voluntary blood donation

Continuous surveillance and preventive strategies are essential to ensure safe blood transfusions and reduce HBV transmission in the community [1–10].

REFERENCES

1. Sharma R, Singh V, Gupta P. Seroprevalence of hepatitis B among blood donors at a tertiary care hospital in North India. Indian J Hematol Blood Transfus. 2018;34(2):245–250.
2. Singh H, Raina V, Gupta N. Seroprevalence of transfusion-transmitted infections among blood donors in central India. Transfus Apher Sci. 2016;55(3):400–405.
3. Kaur P, Bansal M, Singh S. Gender-wise prevalence of hepatitis B infection among blood donors: A tertiary care center study. Asian J Transfus Sci. 2017;11(2):120–124.
4. Raina SK, Singh R, Verma M. Age-wise distribution of hepatitis B seropositivity among blood donors in India: A retrospective study. J Blood Med. 2015;6:13–18.
5. Reddy KP, Kumar K, Rao GR. Prevalence of hepatitis B among blood donors in a tertiary care hospital, Hyderabad. Indian J Public Health. 2019;63(1):45–50.
6. Deshmukh P, Patil S, Choudhary R. Hepatitis B virus seroprevalence in voluntary and replacement donors in western India. J Lab Physicians. 2017;9(4):270–275.
7. Gupta V, Agarwal N, Sharma R. Trends of hepatitis B virus seroprevalence among blood donors over a decade in India. Asian J Transfus Sci. 2018;12(1):15–20.
8. Jain S, Kumar R, Singh P. Seroprevalence of hepatitis B virus among blood donors: A retrospective study. Indian J Hematol Blood Transfus. 2020;36(1):101–106.
9. Patidar GK, Tiwari N, Singh S. Hepatitis B infection among blood donors: a hospital-based study from central India. J Clin Diagn Res. 2016;10(7):EC05–EC08.
10. Global hepatitis report 2017. Geneva: World Health Organization; 2017.