Few studies have shown light on delayed immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a patient with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection. To validate these findings, the authors of the present study hypothesized that previous HIV and HCV infection could increase immune dysfunction providing a differential immune response during the development of coronavirus disease 2019 (COVID-19).

The study included all peer-reviewed articles reporting cases of COVID-19 infection and explicitly defining rates of HBV infection and hospital admission, since 1 December 2019 until 25 March 2020. However, the investigators found a surprisingly low prevalence of chronic HBV in COVID-19 cases admitted to the hospital as among the 2054 cases that were reported with this information, only 28 patients (1.36%) were reported positive for HBV. Various included studies reported 0% incidence of HBV among individuals infected with COVID-19. They also compared the HBV rates in COVID-19 subjects to age-specific rates of HBV observed in the respective geographic areas of origin. 

The outcome showed that median age of COVID-19 infected individuals in the included studies ranged between 47 and 51 years, corresponding with HBV rates ranging from 7% to 11%, whereas the HBV rates of those with COVID-19 continued between 0% and 1.3%. However, it remains debatable as whether this is a simple epidemiological misconnection or if being chronically infected with HBV influences the possibility of clinically marked infection with SARS-CoV-2 resulting in lesser hospital admissions.

Various researches have revealed that chronic HBV infection causes reduced or absent virus-specific T-cell reactivity, which is known as immune exhaustion. This phenomenon is characterized by a reduced ability of T-lymphocytes to produce appropriate cytokines secondary to years of continuous, yet ineffective, immune reaction to the virus. It is also commonly seen in chronic HCV infection. It is thus, can be stipulated that the exhaustion of T lymphocytes may influence their ability to respond to other viruses and decrease the degree of “cytokine storm” that can be commonly seen in COVID-19 patients, resulting in less severe disease. Further studies are required to understand if this epidemiological statistics is a result of immune dysregulation or just coincidence, which in turn, can offer a guidance in to the immunopathology of COVID-19 and can develop potential approaches for prevention and treatment.

Source: Anugwom CM, Aby ES, Debes JD. Inverse Association Between Chronic Hepatitis B Infection and Coronavirus Disease 2019 (COVID-19): Immune Exhaustion or Coincidence? Clin Infect Dis. 2021 Jan 23;72(1):180-182.