ஐ.எஸ்.எஸ்.என்: 2155-9899
Pushkala S, Geethalakshmi S and Gurunathan KS
Introduction: Hepatitis B Virus (HBV) infection is a serious viral infection causes acute and chronic hepatitis. Transfusion of blood and blood products is the predominant route of transmission of HBV. As per NACO guidelines, in India, donor blood is screened for HBsAg, anti-HCV antibodies, anti-HIV antibodies; slide/card rapid screening for malarial parasites and VDRL for Syphilis.
Blood banks in India are only equipped to carry out rapid card test or ELISA for routine screening of HBV, HCV and HIV infections. In developed countries use Nucleic Acid Testing (NAT) were in place for screening and diagnosis of viral infections during window period. NAT assays are highly sensitive, specific and robust but require skilled manpower and specialized infrastructure and thus may not be cost-effective.
Objectives: To explore the current sero-prevalence of HBsAg, Anti-HCV antibodies and anti-HIV antibodies (and other relevant seromarkers) by routine screening tests in a cohort of voluntary blood donors and to determine the efficiency of NAT over the routinely used rapid card and ELISA tests. To include any additional seromarker of HBV infection to detect the antigen in the window period.
Methods: In this cross-sectional observational study, 3160 voluntary blood donors were screened for HBsAg. Samples were also subjected to screening of additional seromarkers such as HbeAg, anti-HBs and anti-HBc antibodies. Thirty samples were randomly selected from each HBsAg positive and HBsAg negative groups and were subjected to HBV DNA PCR for viral load estimation.
Results: ELISA testing is more specific than rapid card test in detecting HBV infection, whereas NAT testing was beneficial in identification of added HBV infection. Both ELISA and rapid card test methods were found to be equally sensitive and specific in diagnosing HCV and HIV infections. NAT testing did not yield any significant increase in positive results compared to serological/rapid methods. HBeAg was found to be positive in 2 samples which are tested negative for HBsAg. HBV DNA was also found to be positive in one sample which is negative for HBsAg (1 out of 30), which might be cryptic HBV infection.
Conclusion: Though NAT would be the choice of screening for Hepatitis B, it not cost-effective. Therefore, inclusion of one or more seromarkers for screening HBV, such as HBeAg, might be helpful in preventing transfusion transmitted infection.