In a study of more than 150 men infected or uninfected with HIV, whether participants received influenza vaccination intradermally or intramuscularly had no impact on cellular immune responses regardless of HIV status, though the response to vaccination was “severely compromised” in participants with low CD4 counts, researchers reported.
“Influenza virus causes an estimated 291,243 to 645,832 fatalities annually and continues to remain a pathogen of significant public health importance. Those especially susceptible to severe illness or complications from influenza infection include young children, pregnant women and immunocompromised individuals like those living with HIV,” Samuel Amoah, PhD, a research scientist for Battelle Memorial Institute, and colleagues wrote in The Journal of Infectious Diseases.
“Although the increased mortality and morbidity seen in populations of HIV-infected people following influenza infection appear to have decreased during the highly active antiretroviral therapy era, health complications remain at levels comparable to other high-risk groups for which annual influenza vaccination is recommended.”
To determine if the route of vaccination affects a patient’s response to it, Amoah and colleagues assessed serological, antigen-specific B cell and interleukin-2, interferon-gamma- and tumor necrosis factor-alpha-secreting T cell responses in 79 HIV-infected and 79 HIV-uninfected men following intradermal or intramuscular influenza vaccination.
According to the study, Amoah and colleagues determined that the route of vaccination, either intradermal or intramuscular, did not affect the immunoglobulin A and immunoglobulin G plasmablast or memory B cell response, “though these were severely impaired” in patients with CD4 counts bellow 200, they said.
According to the findings, frequencies of IgG memory B cells measured at D28 after vaccination were highest in HIV-uninfected patients, followed by patients with CD4 counts of at least 200 and patients with CD4 counts of less than 200.
Amoah and colleagues suggested that passive immunization strategies should be explored to protect individuals with a CD4 count of less than 200.
“Immune responses to influenza vaccine are severely compromised in [the] CD4 less than 200 group; therefore approaches that restore CD4 T cell subset to more than 200 prior to influenza vaccination, or passive transfer of influenza-specific human polyclonal antibodies or a cocktail of influenza-specific human monoclonal antibodies during influenza season could protect the patients with advanced HIV disease,” the authors concluded. – by Caitlyn Stulpin
Disclosures: The authors report no relevant financial disclosures.