Racial/ethnic differences in influenza ( flu ) vaccination coverage in high-risk adults.

OBJECTIVES: This study identified racial/ethnic disparities in influenza ( flu ) vaccination in high-risk adults. METHODS: We analyzed data on influenza ( flu ) vaccination in 7655 adults with high-risk conditions, using data from the 1999 National Health Interview Survey (NHIS). We stratified data by age and used multiple logistic regression to adjust for gender, education, income, employment, and health care access. RESULTS: After control for covariates, White patients with diabetes, chronic heart conditions, and cancer had a higher prevalence of influenza ( flu ) vaccination than did Black patients with the same conditions. Similarly, White patients with 2 or more high-risk conditions were more likely to receive the influenza ( flu ) vaccine than Black patients with the same conditions. CONCLUSIONS: Significant racial/ethnic differences exist in influenza ( flu ) vaccination of high-risk individuals, and missed vaccination opportunities seem to contribute to the less-than-optimal influenza ( flu ) vaccination coverage in the United States.

Human malignant melanoma cell line (HMV-II) for isolation of influenza ( flu ) C and parainfluenza ( flu ) viruses.

HMV-II, a human malignant melanoma cell line, was compared with other cell lines (MDCK, Vero, and LLC-MK2) and primary cultures of monkey kidney (PMK) cells for the isolation and quantification of influenza ( flu ) and parainfluenza ( flu ) viruses. HMV-II cells were superior to MDCK and LLC-MK2 cells in quantification of the influenza ( flu ) C virus and were used successfully in the isolation of the virus from clinical specimens. The HMV-II cell line was also more sensitive for isolating parainfluenza ( flu ) viruses from clinical specimens than were Vero and PMK cells; there was, however, no significant difference in the quantification of the viruses among these cultures. As far as influenza ( flu ) A and B viruses were concerned, the HMV-II cell line was significantly less sensitive than MDCK cells, and no virus was isolated from clinical specimens with HMV-II cells. Thus, HMV-II cells are useful for the isolation of influenza ( flu ) C and parainfluenza ( flu ) viruses as an alternative to embryonated hen's eggs and PMK cells.

Fusion characteristics of influenza ( flu ) C viruses.

A number of different influenza ( flu ) C virus strains were tested for their fusion properties using a resonance energy assay which allows direct monitoring of fusion between virus membranes and artificial lipid vesicles. The fusion pH of various strains was found to range between 5.6 and 6.1. Haemolytic activity of the different strains with chicken erythrocytes was observed at slightly lower pH values and varied between 5.1 and 5.7. Studies of the kinetics of influenza ( flu ) C virus fusion showed distinct characteristics in fusion activity. A lag before onset of fusion was found with influenza ( flu ) C virus which was not observed for influenza ( flu ) A or B viruses. In addition, studies on the rate of conformational change of the influenza ( flu ) C virus glycoprotein, as determined by morphological changes and endogenous tryptophan fluorescence, suggest that the conformational change is rate-limiting in the fusion process, whereas for influenza ( flu ) A viruses the glycoprotein conformational change is fast and a later step in the fusion process is rate-limiting. Monitoring the conformational change of influenza ( flu ) C virus glycoprotein by the onset of trypsin susceptibility showed, however, that membrane fusion occurred in some cases without onset of trypsin susceptibility, indicating that the trypsin-susceptible conformation is a post-fusogenic conformation.

The flu shot study: using multiattribute utility theory to design a vaccination intervention.

Differences between the multiattribute utility (MAU) profiles of participants who had previously gotten flu shots and those who had not done so were used to design an informational brochure urging influenza ( flu ) vaccination. The effectiveness of the MAU brochure was evaluated in a VA ambulatory care clinic with a long-standing influenza ( flu ) vaccination program. The target population for the intervention was high-risk clinic patients who had not gotten a shot the previous year. Participants received either a letter urging them to get a flu shot, or a letter plus the informational brochure. A significantly larger proportion of the patients who received the brochure got shots; 36% versus 23% for the letter only. While a 13 percentage point increase is modest, influenza ( flu ) and related complications (preventable through vaccination) are the fourth-leading killers of older persons. Adding a MAU-based brochure to an ongoing vaccination program is inexpensive and may save additional lives.

The information network of senior citizens in Geneva, Switzerland, and progress in flu vaccination coverage between 1991 and 2000.

Switzerland has lagged behind other industrialized countries in increasing vaccination coverage against flu in the elderly population. The information campaign "United against Flu", started in Geneva in 1993, gradually extended to other French and Italian speaking cantons in Switzerland and indirectly affected German-speaking cantons. Activities developed include the production of TV spots, press conferences, information forwarded to health professionals, an Internet site and information material such as leaflets and posters to risk groups. The campaign is evaluated by repeated surveys that measure vaccination coverage as well as network of informants, knowledge and perceptions in the geriatric population. Vaccination coverage of the geriatric population in Geneva canton has increased from 29% in 1991 to 59% in the year 2000.

Modulation of human natural killer cytotoxicity by influenza ( flu ) virus and its subunit protein.

The influence of intact influenza ( flu ) virus and purified detergent solubilized haemagglutinin (HA) subunits from these viruses on human natural killer (NK) cell activity was examined. Effector cells incubated with whole influenza ( flu ) virus for 18 hr initiated the production of alpha interferon which was associated with the enhancement of NK cell activity. In contrast, purified influenza ( flu ) virus HA suppressed NK activity in a dose-dependent manner, when added at the onset of the cytotoxicity assay, or when used to pre-treated effector cells prior to assay for cytotoxicity against K562 target cells. Effector cells exposed to influenza ( flu ) HA for 90 min, washed and re-incubated in fresh medium for up to 18 hr, failed to regain their cytotoxicity. Suppression of NK cell cytotoxicity could not be ascribed to direct toxicity of HA preparations or residual detergent and preservative in these preparations. The augmented cytotoxicity of activated human effector cells was also susceptible to suppression by virus HA, and pretreatment of human PBL effector cells with HA for 90 min, prior to exposure to human alpha interferon caused NK effector cells to become refractive to the enhancing effects of HIFN. That direct interaction between influenza ( flu ) virus HA and effector cells was a requirement for suppression of activity was shown in experiments using Bromelain-released influenza ( flu ) HA, which would not be expected to bind to cells and which failed to suppress NK cell activity.

Updated interim influenza ( flu ) vaccination recommendations--2004-05 influenza ( flu ) season.

On October 5, 2004, CDC was notified by Chiron Corporation that none of its inactivated influenza ( flu ) vaccine (Fluvirin) would be available for distribution in the United States for the 2004-05 influenza ( flu ) season. At that time, CDC, in coordination with the Advisory Committee on Immunization Practices (ACIP), issued interim recommendations to direct available inactivated influenza ( flu ) vaccine to persons in certain priority groups. CDC has been working with Aventis Pasteur, Inc., to distribute the remaining supply of its inactivated influenza ( flu ) vaccine Fluzone so that it reaches persons in the priority groups established on October 5. In addition, on December 7, the U.S. Department of Health and Human Services announced that up to 4 million doses of the GlaxoSmithKline influenza ( flu ) vaccine Fluarix, authorized for use by the Food and Drug Administration under an Investigational New Drug (IND) application, would be available to help alleviate the influenza ( flu ) vaccine shortage this season.

Characterization of virulent and avirulent A/chicken/Pennsylvania/83 influenza ( flu ) A viruses: potential role of defective interfering RNAs in nature.

In April 1983, an influenza ( flu ) virus of low virulence appeared in chickens in Pennsylvania. Subsequently, in October 1983, the virus became virulent and caused high mortality in poultry. The causative agent has been identified as an influenza ( flu ) virus of the H5N2 serotype. The hemagglutinin is antigenically closely related to tern/South Africa/61 (H5N3) and the neuraminidase is similar to that from human H2N2 strains (e.g., A/Japan/305/57) and from some avian influenza ( Flu ) virus strains (e.g., A/turkey/Mass/66 [H6N2]). Comparison of the genome RNAs of chicken/Penn with other influenza ( flu ) virus isolates by RNA-RNA hybridization indicated that all of the genes of this virus were closely related to those of various other influenza ( flu ) virus isolates from wild birds. Chickens infected with the virulent strain shed high concentrations of virus in their feces (10(7) 50% egg infective dose per g), and the virus was isolated from the albumin and yolk of eggs layed just before death. Virus was also isolated from house flies in chicken houses. Serological and virological studies showed that humans are not susceptible to infection with the virus, but can serve as short-term mechanical carriers. Analysis of the RNA of the viruses isolated in April and October by gel migration and RNA-RNA hybridization suggested that these strains were very closely related. Oligonucleotide mapping of the individual genes of virulent and avirulent strains showed a limited number of changes in the genome RNAs, but no consistent differences between the virulent and avirulent strains that could be correlated with pathogenicity were found. Polyacrylamide gel analysis of the early (avirulent) isolates demonstrated the presence of low-molecular-weight RNA bands which is indicative of defective-interfering particles. These RNAs were not present in the virulent isolates. Experimental infection of chickens with mixtures of the avirulent and virulent strains demonstrated that the avirulent virus interferes with the pathogenicity of the virulent virus. The results suggest that the original avirulent virus was probably derived from influenza ( flu ) viruses from wild birds and that the virulent strain was derived from the avirulent strain by selective adaptation rather than by recombination or the introduction of a new virus into the population. This adaptation may have involved the loss of defective RNAs, as well as mutations, and thus provides a possible model for a role of defective-interfering particles in nature.

Inhibition of cap (m7GpppXm)-dependent endonuclease of influenza ( flu ) virus by 4-substituted 2,4-dioxobutanoic acid compounds.

Synthesis of influenza ( flu ) virus mRNA is primed by capped and methylated (cap 1, m7GpppXm) RNAs which the virus derives by endonucleolytic cleavage from RNA polymerase II transcripts in host cells. The conserved nature of the endonucleolytic processing provides a unique target for the development of antiviral agents for influenza ( flu ) viruses. A series of 4-substituted 2,4-dioxobutanoic acid compounds has been identified as selective inhibitors of this activity in both influenza ( flu ) A and B viruses. These inhibitors exhibited 50% inhibitory concentrations in the range of 0.2 to 29.0 microM for cap-dependent influenza ( flu ) virus transcription and had no effect on the activity of other viral and cellular polymerases when tested at 100- to 500-fold higher concentrations. The compounds did not inhibit the initiation or elongation of influenza ( flu ) virus mRNA synthesis but specifically inhibited the cleavage of capped RNAs by the influenza ( flu ) virus endonuclease and were not inhibitory to the activities of other nucleases. Additionally, the compounds specifically inhibited replication of influenza ( flu ) A and B viruses in cell culture with potencies comparable to the 50% inhibitory concentrations obtained for transcription.

Complete nucleotide sequence of the influenza ( flu ) C/California/78 virus nucleoprotein gene.

The complete nucleotide sequence of RNA segment 5 of the influenza ( flu ) C/California/78 (C/Cal/78) virus was determined by using cloned cDNA derived from viral RNA. The gene contains 1809 nucleotides and can code for a protein of 565 amino acids with a molecular weight of 63 525. The RNA 5 protein of the influenza ( flu ) C/Cal/78 virus possesses two short regions which share a high degree (60-83%) of sequence homology with the nucleoproteins of influenza ( flu ) A and B viruses. These and other structural features of the RNA 5 protein suggest that RNA 5 of influenza ( flu ) C viruses codes for the nucleoprotein. The data also suggest that influenza ( flu ) C viruses are orthomyxoviruses, but that they are more distantly related to either type A or type B viruses than are influenza ( flu ) A and B viruses to each other.