flu
Immunodominance analysis of CTL responses to influenza PR8 virus reveals two new dominant and subdominant Kb-restricted epitopes.

Vitiello A, Yuan L, Chesnut RW, Sidney J, Southwood S, Farness P, Jackson MR, Peterson PA, Sette A.

R.W. Johnson Pharmaceutical Research Institute, San Diego, CA 92121, USA.

In the present study, a systematic analysis of the influenza (Flu) PR8 determinants recognized by H-2b mice was undertaken. A single Db-restricted immunodominant epitope (NP(366)) was previously known in this system. Twenty-three different Flu PR8-derived peptides that bound either Kb or Db molecules in vitro were identified. Sixteen were immunogenic following peptide immunization of C57BL/6 mice, yet CTL induced by peptide immunization recognized PR8-infected target cells only in the case of the NP(366) and NS2(114) epitopes. Similarly, CTL responses following whole-PR8 virus immunization were detected only for the same two determinants. CTL recognizing these dominant epitopes had high avidity for peptide-pulsed target cells, with 5 to 200 pM of peptide required for 30% specific lysis. In contrast, most (80%) of the remaining epitopes were recognized with lower avidity (30% effective concentration in the range of 0.4-50 nM). Repeated in vitro stimulation of primary CTL cultures revealed one additional Kb-restricted epitope (M1(128)). This peptide bound Kb with high affinity (4.6 nM) and induced CTL that effectively recognized PR8-infected cells. These results suggest that 1) this epitope is produced by natural processing in relatively high amounts and 2) low precursor frequency might be related to the subdominant status of the M1(128) epitope. Taken together, these results illustrate the crucial contributions of MHC-binding capacity, and T cell repertoire availability, to the shaping of the repertoire of CTL specificities for Flu Ag virus.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8955206&dopt=Abstract flu, flu medicine, tamiflu



flu
[Vaccination in elderly patients in rehabilitation: a missed opportunity?]

[Article in French]

Bula CJ, Closuit A, Meier-Padel S, Bart PA, Schluter L, Rossier P.

Centre universitaire de traitements et readaptation (CUTR) Sylvana, Epalinges.

BACKGROUND: Immunization against influenza is recommended for elderly persons in Switzerland, but no national guidelines are currently available regarding immunization of the elderly against pneumococcus and tetanus. In addition, almost no data are available regarding immunization rates of the elderly in the general population. In this study we explored the immunization status for influenza, tetanus and pneumococcus of a selected elderly population admitted to a Swiss rehabilitation facility. POPULATION AND METHODS: The study population (n = 145) were patients admitted to a rehab facility during 3 consecutive winter months. Data on demographics, immunization, previous functional status (BADL, IADL), cognitive (MMSE) and affective status (GDS) were collected upon admission. RESULTS: Subjects' mean age was 79.4 years, 32.4% were male, 42.8% had BADLs dependencies and 81.9% IADLs dependencies. Most patients had normal MMSE and GDS scores. Vaccination rates were 39.3% for influenza, 12.4% for tetanus and only 2.1% for pneumococcus. In univariate analyses, people immunized against influenza were older than those who were not (p = 0.01). This relationship remained in multivariate analyses, controlling for gender, functional, cognitive and affective status. Subjects aged 80 and over were 2.5 times (95% CI 1.2-5.5, p = 0.02) more likely to be immunized against influenza, but were less likely to be immunized against tetanus (OR 0.3, 95% CI 0.1-0.9, p = 0.04). Functional status was not significantly associated with any vaccination status. CONCLUSIONS: Immunization rate for influenza in this selected population is similar to those described in US surveys. The positive association between older age and flu vaccination is surprising and needs further investigation. These results also indicate a need to educate patients and physicians in order to increase vaccination use, especially against pneumococcus.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8992629&dopt=Abstract flu, flu medicine, tamiflu



flu
Effect of influenza immunization on immunologic and virologic characteristics of pediatric patients infected with human immunodeficiency virus.

Jackson CR, Vavro CL, Valentine ME, Pennington KN, Lanier ER, Katz SL, Diliberti JH, McKinney RE, Wilfert CM, St Clair MH.

Duke University Medical Center, Durham, NC, USA.

OBJECTIVES: We evaluated the responses of HIV-infected children to a single dose of split-virus influenza vaccine and the relationship to viral load and other characteristics. METHODS: Fifty-three HIV-infected children ages 1.8 to 13.2 years were given influenza vaccine for the 1994 to 1995 influenza season (Wyeth-Ayerst: A/Texas H1N1, A/Shangdong H3N2 and B/Panama). Immunologic and virologic factors were assessed at the time of and 2 to 10 weeks after immunization. RESULTS: The differences between pre- and postimmunization CD4+ counts, CD4+:CD8+ ratios and viral load were not significant. Thirty-one of 53 children (58.4%) had a > 2-fold increase and 16 of 53 (30%) had a 4-fold rise in their postimmunization antibody titers for at least one component of the vaccine. Influenza immunization in the 1993 to 1994 flu season and administration of intravenous immunoglobulin around the time of immunization was not associated with immune response to the vaccine. Factors that were negatively associated with antibody response included increased time between samples (P = 0.004) and decreased preimmunization CD4+:CD8+ ratio (P = 0.02). CONCLUSIONS: Influenza immunization in this population is safe, and a positive antibody response to influenza immunization is not associated with significant clinical events or change in HIV-1 plasma viral burden.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9041601&dopt=Abstract flu, flu medicine, tamiflu



flu
[Which response against the next influenza pandemic?]

[Article in French]

Snacken R.

Institut d'Hygiene et d'Epidemiologie, Bruxelles.

An influenza pandemic is caused by the emergence or the reoccurrence as well as the explosive spreading of a new influenza A virus in an immunologically unprotected population. During this century, three severe pandemics occurred: the Spanish Flu in 1918, the Asian Flu in 1957 and the Hong Kong Flu in 1968. The first one was responsible for 20 millions deaths. A future pandemic is very likely to occur but we cannot predict when it will happen. The mechanism of emergence of a new virus is totally different of the one observed during the annual interpandemic outbreaks. Since the severity of a pandemic virus is unpredictable, action plans must be designed to avoid over-reaction to harmless influenza viruses and at the same time to be adequate in dealing with a threatened new pandemic. Thus these two situations need different control and prevention plans.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9045272&dopt=Abstract flu, flu medicine, tamiflu



flu
The role of germs and viruses in children's theories of AIDS (or, AIDS are not Band-Aids).

Sigelman CK, Alfeld-Liro C, Lewin CB, Derenowski EB, Woods T.

George Washington University, Washington, DC 20052, USA. carol gwis2.circ.gwu.edu

The development of knowledge of germs and viruses in relation to AIDS and flu was examined in a predominantly Mexican American sample of children aged 8-9, 10-11, and 12-13. Children progressed with age from identifying the disease agent for these diseases as a nondescript germ or something other than a germ to implicating a disease-specific germ or virus. Parallel age trends in mastery of the two diseases were observed; gender and ethnic differences were minimal. Solid command of germ and virus concepts in relation to AIDS was associated with more casually sophisticated understanding of the disease but not with more accurate knowledge of modes of HIV transmission. Grasp of flu germ/virus concepts did not contribute to greater understanding or knowledge of AIDS. Overall, children seem predisposed to construct a germ theory of an unfamiliar disease such as AIDS but need help in differentiating between one germ and another.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9079578&dopt=Abstract flu, flu medicine, tamiflu



flu
Influenza immunization cooperative project.

Schiffel F Jr, Klapp S, Elder S, Athon C, Thoenen J, Fortune GJ.

Missouri Patient Care Review Foundation, Jefferson City 65109, USA.

During the 1994 flu season, the Missouri Patient Care Review Foundation (MPCRF) began working on a systems-oriented, hospital-focused influenza immunization project for the 1995-96 flu season with four acute care hospitals. The results of the project indicate that a combination of hospital policies, nurse-driven standing order protocols for immunization, and emphasis on beneficiary education resulted in the highest rate of influenza vaccination.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9214864&dopt=Abstract flu, flu medicine, tamiflu