Poor immunogenicity of the H1N1 2009 vaccine in well controlled HIV-infected individuals.
ABSTRACT To evaluate the safety and immunogenicity of the H1N1 2009 vaccine in HIV-positive individuals.
A single-arm study.
Clinic at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
HIV-infected adults with an indication for H1N1 vaccination.
Single intramuscular 15 microg dose of the monovalent, unadjuvanted, inactivated, split virus H1N1 vaccine.
Immunogenicity, safety and tolerability.
A total of 120 participants were enrolled, 71% men, 68% African-American, with median age of 46 years. All of them but one were on antiretroviral treatment, with a median current CD4 cell counts of 502 cells/microl, and a nadir CD4 cell counts of 132 cells/microl. The HIV RNA level was below 400 copies/ml in 92% of participants. All participants completed the 3 weeks of follow-up. Thirty of the 120 (25%) participants had antibody hemagglutination-inhibition assay titers equal or greater than 1: 40 at baseline. Among participants without evidence of previous exposure, only 61% develop protective titers by week 3 of the study. Nonresponders had lower current and nadir CD4 cell counts than responders. Only four of nine participants with detectable HIV viral load at baseline developed protective antibody titers. Age and race were not predictors of the response to the vaccine. The vaccine was well tolerated.
These results suggest that only 60% of well controlled HIV-infected individuals without preexisting immunity to H1N1 develop protective antibody titers after immunization. Alternative vaccines, dosing, adjuvants or schedule strategies are needed to achieve effective immunization of this vulnerable population.
- [show abstract] [hide abstract]
ABSTRACT: Objective: To assess the humoral response in HIV-infected adults immunised against influenza in Poland in the epidemic season 1997/98.Patients and Methods: The study was carried out in 34 HIV-infected patients in different stages of the disease, vaccinated with a single 0.5ml dose of subunit vaccine (Influvac, Solvay Pharmaceuticals BV). Antihaemagglutinin (HI) antibody levels were measured by the haemagglutinin inhibition test before immunisation and then after one and six months.Results: One month after vaccination HI antibody titres significantly increased from 1.5 to 5.5 times. After six months HI antibody levels were higher than those before vaccination and also higher than those determined one month after vaccination. Before immunisation the number of patients with HI antibody titres 1:40 ranged from 2.9 to 50%. After vaccination, protection rates increased and ranged from 17.6 to 79.4% one month after vaccination, and from 20.6 to 82.4% six months after vaccination. Response rate values remained at similar levels during the whole study and were between 9.4 and 14.7%. No statistically significant differences were found in humoral response between patients with different CD4 counts nor between AIDS patients and those not suffering from AIDS. Significantly higher antibody titres were recorded during the whole study for the A/Wuhan/359/95 (H3N2) influenza strain than for the A(H1N1) and B strains.Conclusions: The results of this study indicated that in HIV-infected patients humoral response to influenza vaccination was poor compared with healthy people. However, in some HIV-infected patients the vaccine induced the production of HI antibodies in titres that were considered high enough to protect against the infection.Clinical Drug Investigation 05/1999; 17(6):441-449. · 1.92 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Data are limited on rates of influenza-associated hospitalizations and deaths among adults younger than 65 years. To quantify serious morbidity and mortality from influenza for women younger than 65 years with and without certain chronic medical conditions, including human immunodeficiency virus infection. Retrospective cohort study. Women aged 15 to 64 years enrolled in the Tennessee Medicaid program from 1974 to 1993. All hospitalizations for and deaths from pneumonia, influenza, and other selected acute cardiopulmonary conditions for women with and without selected chronic medical conditions during 19 consecutive years. Influenza-attributable risk was calculated by subtracting event rates during peri-influenza season (November through April of each year when influenza virus was not circulating) from adjusted rates during influenza season (November through April when influenza virus was circulating). During the 19 years of the study, we identified 53607 acute cardiopulmonary hospitalizations and deaths. Rates of such events were consistently higher during influenza seasons than peri-influenza seasons. Among high-risk women, the estimated annual excess was 23 hospitalizations and deaths per 10000 women aged 15 to 44 years and 58 such events per 10000 women aged 45 to 64 years. The estimated annual excess mortality due to influenza was 2 deaths per 10000 high-risk women for both age groups combined. Among women with no identified high-risk conditions, estimated annual excess hospitalizations and deaths were 4 and 6 per 10000 women aged 15 to 44 and 45 to 64 years, respectively. Women younger than 65 years with certain chronic medical conditions experience substantial morbidity and mortality from acute cardiopulmonary events during influenza season. More effective targeting of these populations for annual influenza immunization is warranted.JAMA The Journal of the American Medical Association 04/1999; 281(10):901-7. · 29.98 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Patients that are immunosuppressed might be at risk of serious influenza-associated complications. As a result, multiple guidelines recommend influenza vaccination for patients infected with HIV, who have received solid-organ transplants, who have received haemopoietic stem-cell transplants, and patients on haemodialysis. However, immunosuppression might also limit vaccine responses. To better inform policy, we reviewed the published work relevant to incidence, outcomes, and prevention of influenza infection in these patients, and in patients being treated chemotherapy and with systemic corticosteroids. Available data suggest that most immunosuppressed populations are indeed at higher risk of influenza-associated complications, have a general trend toward impaired humoral vaccine responses (although these data are mixed), and can be safely vaccinated--although longitudinal data are largely lacking. Randomised clinical trial data were limited to one study of HIV-infected patients with high vaccine efficacy. Better trial data would inform vaccination recommendations on the basis of efficacy and cost in these at-risk populations.The Lancet Infectious Diseases 09/2009; 9(8):493-504. · 19.97 Impact Factor