Severe influenza infection in a chronic hepatitis C carrier: Failure of protective serum HI antibodies after IM vaccination

Background: Influenza is an important cause of morbidity and mortality in immunocompromised hosts. Recommendations exists for vaccination each year, yet disease can still occur. Objectives: To describe the course of fulminant influenza infection in a patient with HCV. Study design: Case study in which correlation was made between immunoglobulin response to influenza vaccination to the disease and its unique clinical course caused by influenza virus. Results: Influenza A/Jerusalem 17/98 (H₁N₁) was isolated from the throat of a chronic hepatitis C carrier who, presented with shortness of breath, and subsequent massive bilateral pneumonia. The patient was previously immunized IM with inactive influenza vaccine. He developed protective levels of humoral antibodies (1:80 hemagglutination inhibition (HI) antibodies) against the three strains of the vaccine that evidently did not prevent respiratory infection. The development of massive bilateral pneumonia and continued presence of influenza virus in the respiratory tract may have been due to his underlying medical condition and possible lack of mucosal secretory IgA (SIgA) antibodies. Conclusion: We have presented a case of prolonged influenza infection post vaccination. This case emphasizes the importance of an improved vaccine that would stimulate a better immunologic response, especially in immunocompromised patients.