Background and aim: Hepatitis A virus (HAV) superinfection is associated with a high risk of liver failure and death in patients with hepatitis C virus (HCV) infection. The aim of this study was to investigate the presence of serological and molecular HAV markers in a population of HCV-infected patients in order to determine a cost-effective strategy to vaccinate against HAV.
Methods: The presence of total and immunoglobulin (Ig)M anti-HAV antibodies was investigated in 399 patients (median age, 50 years; range, 4-81) referred to the Public Health Central Laboratory of Pernambuco State who tested positive for anti-HCV antibodies and HCV RNA. HAV RNA was investigated by reverse transcription-nested polymerase chain reaction in these patients.
Results: Three hundred and eighty-four (96%) patients were positive for anti-HAV total and negative for IgM anti-HAV antibodies (immune patients). Three patients had IgM (and total) anti-HAV antibodies, showing an acute infection, and two of them had HAV RNA detected in serum samples. HAV RNA was also found in another patient in the absence of detectable anti-HAV antibodies. By nucleotide sequencing, it was demonstrated that the HAV isolates infecting these patients belonged to subgenotype 1B.
Conclusion: This study provides valuable new data on anti-HAV prevalence among HCV carriers in Brazil. In the present study, we found a high proportion of patients with anti-HAV positivity, indicating that anti-HAV testing of HCV-infected patients is a cost-effective strategy and should be carried out before vaccination against HAV in these patients, particularly in regions such as our geographical area with high total anti-HAV prevalence.