Immune response to trivalent inactivated influenza vaccine in young and elderly subjects

Longitudinal Analysis of Neuraminidase and Hemagglutinin Antibodies to Influenza A Viruses after Immunization with Seasonal Inactivated Influenza Vaccines

Neuraminidase (NA)-based immunity could reduce the harmful impact of novel antigenic variants of influenza viruses. The detection of neuraminidase-inhibiting (NI) antibodies in parallel with anti-hemagglutinin (HA) antibodies may enhance research on the immunogenicity and duration of antibody responses to influenza vaccines. To assess anti-NA antibodies after vaccination with seasonal inactivated influenza vaccines, we used the enzyme-linked lectin assay, and anti-HA antibodies were detected in the hemagglutination inhibition assay. The dynamics of the anti-NA antibody response differed depending on the virus subtype: antibodies to A/H3N2 virus neuraminidase increased later than antibodies to A/H1N1pdm09 subtype neuraminidase and persisted longer. In contrast to HA antibodies, the fold increase in antibody titers to NA after vaccination poorly depended on the preexisting level. At the same time, NA antibody levels after vaccination directly correlated with titers before vaccination. A difference was found in response to NA antigen between split and subunit-adjuvanted vaccines and in NA functional activity in the vaccine formulations.

Immune defects in the risk of infection and response to vaccination in monoclonal gammopathy of undetermined significance and multiple myeloma

The plasma cell proliferative disorders monoclonal gammopathy of undetermined significance (MGUS) and malignant multiple myeloma (MM) are characterized by an accumulation of transformed clonal plasma cells in the bone marrow and production of monoclonal immunoglobulin. They typically affect an older population, with median age of diagnosis of approximately 70 years. In both disorders, there is an increased risk of infection due to the immunosuppressive effects of disease and conjointly of therapy in MM, and response to vaccination to counter infection is compromised. The underlying factors in a weakened immune response in MGUS and MM are as yet not fully understood. A confounding factor is the onset of normal aging, which quantitatively and qualitatively hampers humoral immunity to affect response to infection and vaccination. In this review, we examine the status of immune alterations in MGUS and MM and set these against normal aging immune responses. We focus primarily on quantitative and functional aspects of B-cell immunity. Furthermore, we review the current knowledge relating to susceptibility to infectious disease in MGUS and MM, and how efficacy of conventional vaccination is affected by proliferative disease-related and therapy-related factors.

Temporal surveillance of the humoral immunity against influenza vaccine in the elderly over 9 consecutive years

BACKGROUND

The effect of age on declining immunity is well established, but its influence on humoral responses to influenza vaccines is still debated.

OBJECTIVE

To compare prospectively the immunogenicity of an influenza vaccine in elderly and healthy control subjects and to search for correlations between this specific humoral protection and clinical and virological parameters.

METHODS

A prospective study of the humoral response to influenza vaccine was conducted over 9 consecutive years in the long-term care units of the Saint-Etienne University Hospital, France. Antibodies directed against the vaccinal strains in an inactivated trivalent vaccine were tested by radial haemolysis before and 1 month after 477 and 242 cumulative annual vaccinations in elderly people and in healthy controls, respectively. During the last 6 years of the study, clinical samples from patients with fever > or =38 degrees C were tested systematically for the diagnosis of an influenza infection.

RESULTS

A significant rise in anti-A/H3N2 antibody titres was observed in 49.3% of the elderly subjects and in 48.3% of the controls (not significant). The rises for the A/H1N1 and B strains were 31.4 and 39.2% (p < 0.001) and 30.6 and 40.5 (p < 0.001), respectively. When control subjects under 31 years old were excluded, no significant difference was recorded for any strain. Only 3.9% of the vaccinated elderly experienced any clinical influenza infection as defined by fever >/=38 degrees C and virological proof.

CONCLUSIONS

The humoral response to influenza immunization is not impaired in the elderly compared with middle-aged controls, and the incidence of febrile episodes due to influenza is low in this vaccinated elderly population. These findings provide further evidence supporting the recommendation for annual influenza vaccination in the elderly.

Influenza vaccination is safe and immunogenic when administered to hospitalized patients

CONTEXT

Very few high-risk persons receive influenza vaccine while hospitalized. Health care providers may be reluctant to administer the influenza vaccine to hospitalized patients because of insufficient data related to the safety and immunogenicity of vaccinating this population.

OBJECTIVE

To evaluate the safety and immunogenicity of the influenza vaccine administered to hospitalized patients compared to ambulatory clinic patients.

DESIGN

Prospective cohort study.

SETTING

A 711-bed, acute-care, private tertiary hospital and two private internal medicine clinics from October 1 to December 25, 1999.

PARTICIPANTS

51 inpatients; 177 outpatients.

INTERVENTION

All study participants received influenza vaccine. Serum samples for antibody assays were collected at baseline and at 3 weeks after vaccination. Study participants were mailed a questionnaire to elicit information about adverse effects of vaccination.

MAIN OUTCOME MEASURE

Seroconversion rates (4-fold increase in hemagglutination-inhibiting antibodies) and seroprotection rates (titers > or = 1:40) to the influenza vaccine in hospitalized and ambulatory patients.

RESULTS

The seroconversion and post-vaccination seroprotection rates in the inpatient group were 65% (33/51) and 88% (45/51) compared to 55% (98/177) and 94% (167/177) in the ambulatory clinic patients. Soreness at the site of injection was the most common adverse effect, reported by 12% of both the inpatients (5/42) and ambulatory clinic patients (20/171). Seventy-four percent of patients (31/41 inpatients and 127/174 outpatients) reported no significant side effect to vaccination.

CONCLUSIONS

Influenza vaccine is at least as safe and immunogenic in hospitalized patients as it is in ambulatory patients. These data can be used to help convince health care providers to order the influenza vaccine for their hospitalized patients.

Dose-dependent antibody response to influenza H1N1 vaccine component in elderly nursing home patients

The effects of an increased antigen dose on HI, IgG, IgA, and IgM antibody responses to influenza A/Taiwan/1/86 (H1N1) were investigated in 92 elderly nursing-home residents (mean age 81 years) and 104 young subjects (mean age 20 years). At a standard 10-microg dose, HI and IgG titer rises were lower in the elderly. HI titers did not improve at higher vaccine dosages. By contrast, influenza-specific IgG and IgA antibody responses were dose dependent in elderly subjects, but not in young. In the young subjects, IgM antibody responses were dose dependent. The improved antibody responses in the elderly as observed in IgG and IgA were not reflected in the HI response. Therefore, the evaluation of antibody production by HI only may lead to an underestimate of the immune response in elderly people.

Altered antibody response to influenza H1N1 vaccine in healthy elderly people as determined by HI, ELISA, and neutralization assay

To determine the influence of ageing per se as well as of priming histories on the antibody response to influenza vaccination, haemagglutination inhibition (HI), ELISA IgG, IgA, IgM and neutralizing antibody titres were studied in 43 healthy young subjects (mean age 23 years) and 55 healthy elderly people (mean age 79 years). The HI and ELISA lgG responses to the A/Guizhou/54/89 strain (H3N2) for which both the young and the elderly had similar priming histories were equal. By contrast, the HI and IgG responses to A/Taiwan/1/86 (H1N1), where the priming histories were different, were lower in the elderly (P < 0.05). Influenza-specific IgA responses in the elderly tended to be higher for all vaccine strains. Influenza-specific postvaccination IgM titres were similar or tended to be higher in the elderly. A subgroup of elderly subjects (18%) who did not express HI activity to the A/Taiwan/1/86 (H1N1) vaccine strain, reacted in the HI assay with the closely related A/Singapore/6/86 (H1N1) strain. These elderly people, however, produced lgG antibodies which neutralized A/Taiwan/1/86 virus in vitro. It is concluded that the elderly are capable of mounting antibody responses similar to those observed in the young. Moreover, the observed age-related differences in antibody responses to H1N1 strains are probably not due to ageing of the immune system itself, but are determined by differences in priming histories.

Simultaneous influenza and pneumococcal vaccination in elderly individuals

The study was performed to evaluate the effects of influenza and pneumococcal vaccines administered alone or in combination. 124 elderly subjects living in community were vaccinated either with influenza split vaccine or with pneumococcal 23-valent or with both vaccines at the same time in different sites. Sera were tested for hemoagglutination inhibiting antibodies for influenza and for antibodies against 23-valent vaccine for streptococcus pneumoniae. No side effects were observed in the vaccinated population. Serological results indicated that influenza vaccine increased significantly antibody levels. No difference was observed between the group which received influenza vaccine alone and that which received influenza and pneumococcal vaccines associated, considering either G.M.T or the percentages of protected individuals or the percentages of subjects who seroconverted. When pneumococcal vaccine was administered at the same time with influenza vaccine, there was a not statistically significant reduction in both mean antibody concentration and mean fold increase. It is concluded that the simultaneous administration of influenza and pneumococcal vaccines to elderly individuals, including subjects at risk, is safe, effective and economically advantageous.

Comparison of humoral immune responses to trivalent influenza split vaccine in young, middle-aged and elderly people

A total of 296 volunteers in five different groups were immunized with one dose of the commercial 1991-1992 trivalent split influenza vaccine formulation A/Singapore/6/86 (H1N1), A/Beijing/353/89 (H3N2) and B/Yamagata/16/88. The groups differed in age (young adults, middle-aged and elderly) and history of previous vaccination. Antibodies were determined in pre- and postvaccination sera by haemagglutination inhibition assay and the results were evaluated as geometric mean titre, mean fold antibody increase, protection and response rates. No significant age-related differences among the protection rates were found. The proportion of vaccinees with antibodies > or = 40 ranged between 70 and 95%. Compared with the H3N2 and B components the antibody response to the H1N1-component was low. Residents of a nursing home fully vaccinated the previous year developed 7.6-8.4-fold antibody increases and showed 96-100% protection rates.

Antibody response after influenza immunization with various vaccine doses: a double-blind, placebo-controlled, multi-centre, dose-response study in elderly nursing-home residents and young volunteers

The dose effect (0, 10, 20 and 60 micrograms) of influenza subunit vaccine on the antibody response was investigated in nursing-home residents and young controls. The vaccine antigens were: A/Taiwan/1/86 (H1N1), A/Sichuan/2/87 (H3N2) and B/Beijing/1/87. For the influenza B antigen, the post-GMT and the 'percentage protective titre' increased significantly both in the young controls and nursing-home residents. No dose effect was observed for the A/Taiwan, and a minor dose effect for A/Sichuan. All vaccine doses were well tolerated by both groups. We conclude from our data that higher vaccine doses may result in a better antibody response against some antigens but not against others. Therefore, in general, increasing the vaccine dose is no adequate method to improve the antibody response.

Immunization of elderly volunteers with the 1988-89 inactivated whole influenza vaccine: assessment of antibody responses by haemagglutination inhibition and single radial haemolysis tests

The immunogenicity of inactivated whole trivalent influenza vaccines (A/Taiwan/1/86 (H1N1), A/Sichuan/2/87 (H3N2), and B ijing/1/87) recommended for the 1988-89 winter season was evaluated in 236 elderly (mean age 71 years) high risk volunteers. An overall significant increase in the number of subjects with protective haemagglutination inhibiting (HI) antibodies (titer > 1:40) against vaccine components was observed after vaccination. Nevertheless, a percentage of individuals (ranging from 56% to 62%) remained without protective antibodies and the number of people showing a positive response was limited (from 32% to 41%). By the comparative analysis of the results obtained examining the presence of protective levels of antibody in the sera from 91 volunteers using HI versus the single radial haemolysis (SRH) test, we obtained evidence for a higher sensitivity of SRH technique especially against B antigen.

Immunogenicity of trivalent subunit and split influenza vaccines (1989-90 winter season) in volunteers of different groups of age

Trivalent split or subunit influenza vaccines [A/Shangai/11/87 (H3N2), A/Singapore/6/86 (H1N1) and B/Yamagata/16/88] recommended for the 1989-90 winter season and licensed in Italy, were administered to 149 volunteers of three different age groups (elderly, middle-aged and young). Antibody production was determined in pre- and postvaccination sera by haemagglutinin inhibition test and the results were evaluated as protection and response rates. The split vaccine was more immunogenic than the subunit preparation, especially against the B virus strain. Age had no obvious impact on the degree of responsiveness to vaccination.