Molecular epidemiology of hepatitis B virus genotypes in blood donors in Islamabad, Pakistan

Molecular and genetic characterization of hepatitis B virus among multitransfused thalassaemia patients in Islamabad, Pakistan

Background:

Hepatitis B virus (HBV) is the aetiological agent of transfusion-transmitted hepatitis globally. Beta thalassaemia major individuals are at greater risk of contracting HBV infection due to multiple blood transfusions required for the medical management of these patients. Based on HBV genetic variability, it is divided into 10 genotypes. The determination of HBV genotypes has significant implications for clinical management and treatment regimens.

Aim:

This study was performed to assess the HBV epidemiology and circulating genotypes in multi-transfused β-thalassemia major patients with the aim to be considered while formulating the treatment pattern taking into account particular needs of thalassaemia patients.

Materials and Methods:

This study was performed from September 2018 to June 2019, at the Department of Pathology and Transfusion Medicine, Shaheed Zulfiqar Ali Bhutto (SZAB) Medical University, Islamabad. A total of 2,260 thalassaemia patients were enrolled in the study. The study was endorsed by the Ethics Committee of the SZAB Medical University, Islamabad. The samples were serologically screened for HBsAg on the LIAISON® XL Murex HBsAg Quant assay (DiaSorin S.p.A., Italy) a chemiluminescence based immunoassay (CLIA). HBV quantitative PCR kit was used to measure the HBV DNA in serum samples. The HBV genotypes were determined using universal primers targeting the P1 and S1 region amplification.

Results:

Of 2,260 thalassaemia patients, 64.6% were males while 35.4% were females. The HBsAg was identified in 98 individuals (4.33%). The PCR analysis was done for these 98 patients and in this cohort, genotype D was 59.18% (n = 58), genotype A was 21.42% (n = 21) while genotype C was 19.38% (n = 19).

Conclusion:

The determination of HBV genotypes in the multi-transfused patients is key to the effective management of chronic HBV patients as the severity and course of the disease is dependent on a specific type of genotypes. Quality assured screening of donated blood will prevent the incidence of HBV in thalassaemia patients.

A Systematic Review of Transfusion-Transmissible Infections Among Blood Donors and Associated Safety Challenges in Pakistan

The blood transfusion (BT) system in Pakistan is fragmented, demand-driven and depends on weakly regulated transfusion practices. There is a considerable possibility that transfusion-transmissible infections (TTIs) are contributing to the current epidemic of hepatitis B virus (HBV) and hepatitis C virus (HCV) (affecting 7.4% of the general population) in the country. To study this issue, we conducted a systematic review to identify articles related to TTIs and transfusion safety in Pakistan from January 1, 2010 to January 31, 2020. A review of 33 articles met the final criteria for qualitative synthesis. Analysis of these studies showed a cumulative frequency of HBV 2.04%, HCV 2.44%, HIV 0.038%, syphilis 1.1% and malaria 0.11%. The frequency of coinfections among blood donors varied from 0.0099% to 0.35%. The highest number of coinfections were HCV and syphilis, followed by HCV and HBV infections. Syphilis and malaria were tested in only 38% and 46% of all the blood donations in one study. The rate of voluntary non-remunerated donations (VNRDs) was less than 13%, and male donors were 95% to 100% in these studies. There was a significant difference in the frequency of HBV and HCV in VNRDs (0.48%) as compared to replacement donors (RDs) (4.15%). In short, this review shows a high frequency of TTIs, especially HBV, HCV and syphilis in the blood donor population in Pakistan. There is a high dependency on RDs, minimal use of healthy voluntary blood donation practices, inadequate screening of high-risk donors, repeated collections of the blood from RDs, poor quality of screening methods and limited knowledge of donor health. Without standardized safe transfusion practices, there will be an ongoing increase in transmission of TTIs, especially HBV, HCV, syphilis, and HIV leading to a significant adverse public health impact.