IntroductionHepatitis is one of the major diseases of mankind and is a serious global public health problem. The diagnosis of the disease is not only imperative but also complex because of different viral antigens, which bring about varying serological profiles during different stages of the disease. Recently, new forms of infection such as occult infections of HBV are being reported. Occult HBV infections are defined as the presence of low-level of HBV DNA in blood in patients negative for markers of hepatitis B. ObjectiveThe aim of the present study was the molecular identification and clinical immune characterization of occult HBV infections in the routine health workers and blood donors at Bhopal Memorial Hospital & Research Centre.Materials & MethodsA total of 1000 samples of blood donors and 100 healthy health care workers were undertaken for the study. Qualitative screening for HBV was done through ELISA while the nucleic acid analysis was performed through COBAS Amplicor Analyzer (minimum detection limit 300 copies/ml) and the negative samples were further confirmed with the Light Cycler 2.0 (minimum detection limit 10 copies/ml). In addition, Th1/Th2 cytokine profiling was done for immune characterization of these infections. ResultsIt was observed that all the samples were negative for the HBV in qualitative screening through standard ELISA. Further nucleic acid analysis through COBAS Amplicor Analyzer showed that 22 cases of blood donors were positive for HBV DNA which was previously reported negative in ELISA while no healthcare worker reported positive. All the samples reported negative by COBAS Amplicor were again confirmed by real time PCR and the similar results were obtained. Additionally, a significant increase in the mean levels of Th2 cytokines IL-4, IL-6 and IL-10 in occult cases was observed in comparison to controls.ConclusionIn conclusion it is a unique attempt to determine the frequency and importance of this occult phenomenon. Results of such investigations should provide and improve the basic knowledge necessary to specifically understand on the grounds of occult HBV infections. This background provides the scientific basis for the wide range of investigations. It would not only create health awareness, but would also evoke a perpetual social consciousness about the upcoming infectious states of these diseases.