Publications

influenza a (h3n2) outbreak, nepal.	in july 2004, an outbreak of influenza a (h3n2) was detected at 3 bhutanese refugee camps in southeastern nepal. hemagglutination inhibition showed that approximately 40% of the viruses from this outbreak were antigenically distinct from the a/wyoming/3/03 vaccine strain. four amino acid differences were observed in most of the 26 isolates compared with the a/wyoming/3/2003 vaccine strain. all 4 substitutions are located within or adjacent to known antibody-binding sites. several isolates showed ...	2005	16102305
influenza in taiwan: seasonality and vaccine strain match.	this article explores seasonality, epidemiology and dominant epidemic strains of influenza in taiwan. surveillance in taiwan demonstrates that influenza is a disease which occurs throughout the year but has peak activity in winter. due to the high mutability of influenza virus, effective vaccination is the best strategy for protection. although the world health organization-recommended vaccine compositions usually matched with around 77% of circulating strains worldwide, the rate of matching in ...	2005	16118670
annual report of the national influenza surveillance scheme, 2004.	the national influenza surveillance scheme includes data on influenza-like illness from sentinel general practitioner practices, laboratory reports of influenza from national notifiable diseases surveillance scheme and absenteeism data from a national employer. in 2004, 2,116 cases of laboratory-confirmed influenza-like illness were reported, which was 41 per cent lower than the previous year. peak activity was recorded in september, a month later than in 2003. influenza a was again predominant ...	2005	16119760
respiratory disease caused by a species b2 adenovirus in a military camp in turkey.	in april 2004, two patients were admitted to hospital in berlin, germany, with clinical signs of acute respiratory infection after returning from a military exercise in their home country of turkey. they were admitted to a high security infectious disease unit as epidemiological data pointed to an outbreak of unknown etiology. samples taken at the time of admission proved to be strongly positive for adenovirus by pcr, but negative for influenza a/h1n1 virus, influenza a/h3n2 virus, influenza b v ...	2005	16121380
sensitivity of influenza viruses to zanamivir and oseltamivir: a study performed on viruses circulating in france prior to the introduction of neuraminidase inhibitors in clinical practice.	influenza virus neuraminidase inhibitors (nais) were introduced in clinical practice in various parts of the world since 1999 but were only scarcely distributed in france. prior to the generalization of zanamivir and oseltamivir utilization in our country, we decided to test a large panel of influenza strains to establish the baseline sensitivity of these viruses to anti-neuraminidase drugs, based upon a fluorometric neuraminidase enzymatic test. our study was performed on clinical samples colle ...	2005	16125799
antiviral effect of catechins in green tea on influenza virus.	polyphenolic compound catechins ((-)-epigallocatechin gallate (egcg), (-)-epicatechin gallate (ecg) and (-)-epigallocatechin (egc)) from green tea were evaluated for their ability to inhibit influenza virus replication in cell culture and for potentially direct virucidal effect. among the test compounds, the egcg and ecg were found to be potent inhibitors of influenza virus replication in mdck cell culture and this effect was observed in all influenza virus subtypes tested, including a/h1n1, a/h ...	2005	16137775
sialidase activity of influenza a virus in an endocytic pathway enhances viral replication.	n2 neuraminidase (na) genes of the 1957 and 1968 pandemic influenza virus strains possessed avian-like low-ph stability of sialidase activity, unlike most epidemic strains. we generated four reverse-genetics viruses from a genetic background of a/wsn/33 (h1n1) that included parental n2 nas of 1968 pandemic (h3n2) and epidemic (h2n2) strains or their counterpart n2 nas in which the low-ph stability of the sialidase activity was changed by substitutions of one or two amino acid residues. we found ...	2005	16140748
influenza immunisation in children with solid tumours.	we assessed response to immunisation with trivalent split virus influenza vaccine in children with non-leukaemic malignant disease. children with solid tumours and lymphoma received one or two doses of influenza vaccine, according to current uk guidelines, in autumn 2001 and/or 2002. children were currently receiving chemotherapy or were within 6 months of completing chemotherapy. pre and post vaccination sera were assessed for antibodies to the prevalent influenza strains by haemagglutination i ...	2005	16143516
the origins of new pandemic viruses: the acquisition of new host ranges by canine parvovirus and influenza a viruses.	transfer of viruses between hosts to create a new self-sustaining epidemic is rare; however, those new viruses can cause severe outbreaks. examples of such viruses include three pandemic human influenza a viruses and canine parvovirus in dogs. in each case one virus made the original transfer and spread worldwide, and then further adaptation resulted in the emergence of variants worldwide. for the influenza viruses several changes were required for growth and spread between humans, and the emerg ...	2005	16153179
implementation of the community network of reference laboratories for human influenza in europe.	the increased need for accurate influenza laboratory surveillance data in the european union required formalisation of the existing network of collaborating national influenza reference laboratories participating in the european influenza surveillance scheme (eiss).	2005	16157259
the cotton rat provides a useful small-animal model for the study of influenza virus pathogenesis.	influenza a virus continues to cause annual epidemics. the emergence of avian viruses in the human population poses a pandemic threat, and has highlighted the need for more effective influenza vaccines and antivirals. development of such therapeutics would be enhanced by the use of a small-animal model that is permissive for replication of human influenza virus, and for which reagents are available to dissect the host response. a model is presented of nasal and pulmonary infection in adult inbre ...	2005	16186238
neuraminidase inhibitor-resistant influenza viruses may differ substantially in fitness and transmissibility.	mutations of the conserved residues of influenza virus neuraminidase (na) that are associated with na inhibitor (nai) resistance decrease the sialidase activity and/or stability of the na, thus compromising viral fitness. in fact, clinically derived nai-resistant variants with different na mutations have shown different transmissibilities in ferrets (m. l. herlocher, r. truscon, s. elias, h. yen, n. a. roberts, s. e. ohmit, and a. s. monto, j. infect. dis. 190:1627-1630, 2004). molecular charact ...	2005	16189083
[sequence analysis of the ha1 regions of hemagglutinin gene from influenza viruses (h3n2) isolated from children in beijing in 2004 indicated antigenic variation].	to identify variations in hemagglutinin genes from influenza viruses (h3n2) isolated from infants and young children with acute respiratory infection (ari) between march, 2004 and april 2005.	2005	16191295
[in vitro study of antiviral activity of myramistin against subtypes h3n2 and h5n1 of influenza virus].	in vitro antiviral effect of myramistin on influenza virus (mdck cell culture) was studied. the drug showed significant dose-dependent antiviral activity against the virus. when used prophylactically (1 hour before exposure to the virus) in subtoxic doses, myramistin was effective in inhibiting replication of the influenza virus [strains a/aichi/2/68 (h3n2) and a/chicken/suzdalka/nov-11/2005 (h5n1)]. in urgent prophylaxis (1 hour after exposure to the virus) the protective effect was less pronou ...	2005	19140480
influenza a/fujian/411/02(h3n2)-lineage viruses in finland: genetic diversity, epidemic activity and vaccination-induced antibody response.	the first sporadic cases of fujian/411/02-lineage viruses were recorded in finland in winter 2001-2002. the first protracted but low-intensity outbreak occurred here during the first half of 2003, and the second outbreak early in autumn 2003, after detection of sporadic influenza a cases in the summer. the calculated incidence of influenza a in the finnish army was 515/10000 during the first outbreak and 2066/10000 during the second outbreak. during the 2003-2004 epidemic season, the isolates fe ...	2006	16195790
amplification of the entire genome of influenza a virus h1n1 and h3n2 subtypes by reverse-transcription polymerase chain reaction.	this study describes the development of a simple rt-pcr method to amplify the whole genome of the influenza a virus based on the amplification of full-length gene segments. primers were designed based on the conserved regions of both the 5'-end and the 3'-end of each gene segment. after optimizing the duration and temperature of denaturing, annealing, and extension, these primers could amplify all of the full-length gene segments. to test the accuracy of the method, all amplicons were subjected ...	2006	16687177
novel swine influenza virus subtype h3n1, united states.	influenza a virus infects various animal species and transmits among different hosts, especially between humans and swine. swine may serve as a mixing vessel to create new reassortants that could infect humans. thus, monitoring and characterizing influenza viruses in swine are important in preventing interspecies transmission. we report the emergence and characterization of a novel h3n1 subtype of swine influenza virus (siv) in the united states. phylogenetic analysis showed that the h3n1 sivs m ...	2006	16704839
protection against influenza virus infection by intranasal vaccine with surf clam microparticles (smp) as an adjuvant.	a safe and effective adjuvant is necessary to enhance mucosal immune responses for the development of an inactivated intranasal influenza vaccine. the present study demonstrated the effectiveness of surf clam microparticles (smp) derived from natural surf clams as an adjuvant for an intranasal influenza vaccine. the adjuvant effect of smp was examined when co-administered intranasally with inactivated a/pr8 (h1n1) influenza virus hemagglutinin vaccine in balb/c mice. administration of the vaccin ...	2006	16721854
in vitro inhibition of human influenza a virus replication by chloroquine.	chloroquine is a 9-aminoquinolone with well-known anti-malarial effects. it has biochemical properties that could be applied to inhibit viral replication. we report here that chloroquine is able to inhibit influenza a virus replication, in vitro, and the ic50s of chloroquine against influenza a viruses h1n1 and h3n2 are lower than the plasma concentrations reached during treatment of acute malaria. the potential of chloroquine to be added to the limited range of anti-influenza drugs should be ex ...	2006	16729896
systemic capillary leak syndrome presenting as recurrent shock.	to report a case of systemic capillary leak syndrome (scls) in a child.	2006	16738498
genetic characterization of novel reassortant h1n2 influenza a viruses isolated from pigs in southeastern china.	in december 2004, three influenza h1n2 viruses were isolated from lung samples of pigs that had died from respiratory disease on a farm in southeastern china. to determine the genetic characterization and probable origin, one of the three isolates, a/swine/zhejiang/1/2004 (sw/zj/1/2004), was genetically analyzed. sw/zj/1/2004 was a reassortant with an na gene most closely related to the corresponding gene from a human-like h3n2 virus circulating in 1995. the remaining seven genes were most close ...	2006	16755371
[internal epidemic influenza virus proteins: isolation and investigation].	the internal influenza virus proteins m1 and rnp free from surface protein impurities were isolated from subviral particles (virions free from ha and na ectomenes). the spikeless particles had no propensity to aggregate in the solution at ph 5.0 as compared with native viruses. the subviral particles of b/hong kong/330/01 influenza virus, which belonged to b/victoria/2/87-lineage, were obtained by proteolytic treatment with the enzyme bromelain under the same conditions as in cases of influenza ...	2006	16756174
epidemiological and virological assessment of influenza activity in europe, during the 2004-2005 winter.	the 2004-2005 influenza season in europe started in late december 2004 and the first influenza activity occurred in the west and southwest (spain, united kingdom and ireland). influenza activity then moved gradually east across europe during january and early february 2005, and from late february until late march, most movement was south to north. the intensity of clinical influenza activity in ten out of 23 countries was higher than during the 2003-2004 season, and lower or equal to the 2003-20 ...	2006	16757850
cross-reactivity of influenza a (h3n2) hemagglutination-inhibition antibodies induced by an inactivated influenza vaccine.	the antigenic drift of influenza a (h3n2) virus in 2003-2004 necessitated a change in the vaccine from the a/panama to the a/wyoming strain for the 2004-2005 season. using hemagglutination inhibition, we therefore tested antibodies in sera of 39 individuals (mean age 64.6 years) at the end of the 2003-2004 season for cross-reactivity to vaccine strains and h3n2 antigens subject to antigenic drift. antibodies against both a (h3n2) panama and wyoming developed in 5/13 (38.5%) unvaccinated individu ...	2006	16777274
[influenza diagnostics in patient with leukemia suspicion].	influenza is a seasonal viral disease, with the peak of morbidity occurring in poland between january and march. it is estimated that up to 70% of respiratory infections during the season is caused by this virus. influenza virus infection poses an ultimate threat to the elderly > or = 65 years old and chronically ill, in whom postinfluenzal complications--including viral pneumonia and secondary bacterial pneumonia--cause from 0.1% to 0.4% deaths annually. influenza also triggers off from 5% to 7 ...	2006	16780271
the guinea pig as a transmission model for human influenza viruses.	the severity of epidemic and pandemic influenza outbreaks is dictated in part by the efficiency with which the causative strain transmits between human hosts. the mechanisms underlying influenza virus spread are poorly understood, in part because of the lack of a convenient animal model to study this phenomenon. indeed, despite extremely efficient transmission among humans and virulence in the mouse model, we have shown that even the 1918 pandemic influenza virus does not transmit between mice. ...	2006	16785447
variation in the ability of human influenza a viruses to induce and inhibit the ifn-beta pathway.	we investigated the ability of a selection of human influenza a viruses, including recent clinical isolates, to induce ifn-beta production in cultured cell lines. in contrast to the well-characterized laboratory strain a/pr/8/34, several, but not all, recent isolates of h3n2 viruses resulted in moderate ifn-beta stimulation. through the generation of recombinant viruses, we were able to show that this is not due to a loss of the ability of the ns1 genes to suppress ifn-beta induction; indeed, th ...	2006	16378631
an epidemiologically significant epitope of a 1998 human influenza virus neuraminidase forms a highly hydrated interface in the na-antibody complex.	the crystal structure of the complex between neuraminidase (na) of influenza virus a/memphis/31/98 (h3n2) and fab of monoclonal antibody mem5 has been determined at 2.1a resolution and shows a novel pattern of interactions compared to other na-fab structures. the interface buries a large area of 2400 a2 and the surfaces have high complementarity. however, the interface is also highly hydrated. there are 33 water molecules in the interface>or=95% buried from bulk solvent, but only 13 of these are ...	2006	16384583
surveillance of respiratory virus infections in adult hospital admissions using rapid methods.	both influenza and respiratory syncytial virus (rsv) cause epidemics of respiratory illness of variable severity during the winter season. influenza in particular has been blamed for hospital winter bed pressures, although it is thought that rsv may also play a role. human metapneumovirus (hmpv) is a new respiratory virus reported to be important in children; only a limited number of studies are available for adult populations. we aimed to determine initially the burden of virologically confirme ...	2006	16388686
patterns of influenza-associated mortality among us elderly by geographic region and virus subtype, 1968-1998.	the regular seasonality of influenza in temperate countries is recognized, but regional differences in patterns of influenza-related mortality are poorly understood. identifying patterns could improve epidemic prediction and prevention. the authors analyzed the monthly percentage of deaths attributable to pneumonia and influenza among people aged 65 or more years in the contiguous united states, 1968-1998. the local moran's i test for spatial autocorrelation and correlograms assessing space-time ...	2006	16394205
viral pneumonia in older adults.	viruses account for a substantial portion of respiratory illnesses, including pneumonia, in the elderly population. presently, influenza virus a h3n2 and respiratory syncytial virus are the most commonly identified viral pathogens in older adults with viral pneumonia. as diagnostic tests such as reverse-transcription polymerase chain reaction become more widely used, the relative importance of additional viruses (such as parainfluenza, rhinoviruses, coronaviruses, and human metapneumovirus) will ...	2006	16421796
heterocyclic rimantadine analogues with antiviral activity.	2-(1-adamantyl)-2-methyl-pyrrolidines 3 and 4, 2-(1-adamantyl)-2-methyl-azetidines 5 and 6, and 2-(1-adamantyl)-2-methyl-aziridines 7 and 8 were synthesized and tested for their antiviral activity against influenza a. parent molecules 3, 5, and 7 contain the alpha-methyl-1-adamantan-methanamine 2 pharmacophoric moiety (rimantadine). the ring size effect on anti-influenza a activity was investigated. pyrrolidine 3 was the most potent anti-influenza virus a compound, 9-fold more potent than rimant ...	2006	16439137
influenza pandemics: past, present and future.	influenza a virus is well known for its capability for genetic changes either through antigen drift or antigen shift. antigen shift is derived from reassortment of gene segments between viruses, and may result in an antigenically novel virus that is capable of causing a worldwide pandemic. as we trace backwards through the history of influenza pandemics, a repeating pattern can be observed, namely, a limited wave in the first year followed by global spread in the following year. in the 20th cent ...	2006	16440064
avian influenza viruses and human health.	influenza a viruses cause natural infections of humans, some other mammals and birds. few of the 16 haemagglutinin and nine neuraminidase subtype combinations have been isolated from mammals, but all subtypes have been isolated from birds. in the 20th century, there were four pandemics of influenza as a result of the emergence of antigenically different strains in humans: 1918 (h1n1), 1957 (h2n2), 1968 (h3n2) and 1977 (h1n1). influenza a viruses contain eight distinct rna genes and reassortment ...	2006	16447497
restricted infectivity of a human-lineage h3n2 influenza a virus in pigs is hemagglutinin and neuraminidase gene dependent.	influenza a viruses cause pandemics at sporadic intervals. pandemic viruses can potentially be introduced into the human population through in toto transfer of an avian influenza virus or through reassortment between avian and human strains. pigs are believed to play a central role in the creation of pandemic viruses through reassortment because of their susceptibility to infection with both avian and human influenza viruses. however, we recently found that a human-lineage h3n2 influenza virus w ...	2006	16455873
adamantane resistance among influenza a viruses isolated early during the 2005-2006 influenza season in the united states.	the adamantanes, amantadine and rimantadine, have been used as first-choice antiviral drugs against community outbreaks of influenza a viruses for many years. rates of viruses resistant to these drugs have been increasing globally. rapid surveillance for the emergence and spread of resistant viruses has become critical for appropriate treatment of patients.	2006	16456087
an mf59-adjuvanted inactivated influenza vaccine containing a/panama/1999 (h3n2) induced broader serological protection against heterovariant influenza virus strain a/fujian/2002 than a subunit and a split influenza vaccine.	to test whether inactivated influenza vaccines distributed during the 2003-2004 influenza season in the northern hemisphere were able to confer protection against the mismatched variant a/fujian/411/2002 virus strain, we measured haemagglutination inhibiting (hi) antibodies in elderly subjects vaccinated with three inactivated vaccines against the homologous a/h3n2 vaccine strain (a/panama) and against the mismatched a/fujian strain. the results showed that, while 76 to 80% of elder people vacci ...	2006	16464520
an unexpected antibody response to an engineered influenza virus modifies cd8+ t cell responses.	the ovalbumin(323-339) peptide that binds h2i-a(b) was engineered into the globular heads of hemagglutinin (h) molecules from serologically non-cross-reactive h1n1 and h3n2 influenza a viruses, the aim being to analyze recall cd4+ t cell responses in a virus-induced respiratory disease. prime/challenge experiments with these h1ova and h3ova viruses in h2(b) mice gave the predicted, ovalbumin-specific cd4+ t cell response but showed an unexpectedly enhanced, early expansion of viral epitope-speci ...	2006	16473934
an rna aptamer that distinguishes between closely related human influenza viruses and inhibits haemagglutinin-mediated membrane fusion.	aptamers selected against various kinds of targets have shown remarkable specificity and affinity, similar to those displayed by antibodies to their antigens. to employ aptamers as genotyping reagents for the identification of pathogens and their strains, in vitro selections were carried out to find aptamers that specifically bind and distinguish the closely related human influenza a virus subtype h3n2. the selected aptamer, p30-10-16, binds specifically to the haemagglutinin (ha) region of the ...	2006	16476969
serum antibodies against circulating influenza strains among vaccinated and unvaccinated general practitioners during two consecutive years (2002-2003).	efficacy studies have not answered the question whether influenza vaccination among general practitioners (gps) has a substantial additive effect on their immunity. to evaluate this effect the influenza antibody titres in vaccinated and unvaccinated gps were compared in a controlled trial during two consecutive winter periods (2002-2003 and 2003-2004). the seroprotection rates against the circulating a/h3n2 influenza virus amount to 80% and 42% in the unvaccinated group in 2002 and 2003, respect ...	2006	16490288
influenza pandemics of the 20th century.	three worldwide (pandemic) outbreaks of influenza occurred in the 20th century: in 1918, 1957, and 1968. the latter 2 were in the era of modern virology and most thoroughly characterized. all 3 have been informally identified by their presumed sites of origin as spanish, asian, and hong kong influenza, respectively. they are now known to represent 3 different antigenic subtypes of influenza a virus: h1n1, h2n2, and h3n2, respectively. not classified as true pandemics are 3 notable epidemics: a p ...	2006	16494710
swine influenza a outbreak, fort dix, new jersey, 1976.	in early 1976, the novel a/new jersey/76 (hsw1n1) influenza virus caused severe respiratory illness in 13 soldiers with 1 death at fort dix, new jersey. since a/new jersey was similar to the 1918-1919 pandemic virus, rapid outbreak assessment and enhanced surveillance were initiated. a/new jersey virus was detected only from january 19 to february 9 and did not spread beyond fort dix. a/victoria/75 (h3n2) spread simultaneously, also caused illness, and persisted until march. up to 230 soldiers w ...	2006	16494712
influenza-associated deaths in tropical singapore.	we used a regression model to examine the impact of influenza on death rates in tropical singapore for the period 1996-2003. influenza a (h3n2) was the predominant circulating influenza virus subtype, with consistently significant and robust effect on mortality rates. influenza was associated with an annual death rate from all causes, from underlying pneumonia and influenza, and from underlying circulatory and respiratory conditions of 14.8 (95% confidence interval 9.8-19.8), 2.9 (1.0-5.0), and ...	2006	16494727
[characterization of epidemic influenza virus a(h3n2) strains circulating in russia in the 2003-2004 epidemic season].	studies indicated that the epidemic rise in the incidence of influenza was caused by its virus a (h3n2) circulation in russia in the 2003-2004 season. the center of influenza ecology and epidemiology investigated 101 epidemic strains isolated the mdck culture. antigenic analysis showed that all viruses a(h3n2) were similar to the reference virus a/fujian/411/02(h3n2) and only 5 strains slightly differed from the latter. twelve (14%) strains resistant to rimantadine at a concentration of 0.5 mg/m ...	2006	16515037
influenza-associated hospitalization in a subtropical city.	the impact of influenza on morbidity and hospitalization in the tropics and subtropics is poorly quantified. uniquely, the hong kong special administrative region has computerized hospital discharge diagnoses on 95% of total bed days, allowing disease burden for a well-defined population to be accurately assessed.	2006	16515368
combination chemotherapy, a potential strategy for reducing the emergence of drug-resistant influenza a variants.	rapid development of resistant influenza variants after amantadine treatment is one of the main drawbacks of m2 blockers. on the other hand, the emergence of variants with low susceptibility to the neuraminidase (na) inhibitors is limited. in the present study we examined whether combination therapy with two classes of anti-influenza drugs can affect the emergence of resistant variants in vitro. we observed that virus yields of human a/nanchang/1/99 (h1n1), a/panama/2007/99 (h3n2), and a/hong ko ...	2006	16516984
[influenza pandemic--current crisis].	in most cases, influenza is not fatal, even without treatment. moreover, vaccination and antivirals have reduced influenza-related mortality in recent years. however, the direct transmission of avian influenza viruses to humans with lethal outcomes in hong kong in 1997 was a potent reminder of the devastating potential of the disease. currently, h5n1 avian influenza viruses are circulating in many asian countries, and the human death toll continues to rise as the virus spreads to european countr ...	2006	16519118
activation of the intrinsic mitochondrial apoptotic pathway in swine influenza virus-mediated cell death.	the mitochondrial pathway of swine influenza virus (siv)-induced apoptosis was investigated using porcine kidney (pk-15) cells, swine testicle (st) cells, and hela cervical carcinoma cells which are known not to support viral replication. as judged by cell morphology, annexin v staining, and dna fragmentation, pk-15 and st cells infected with three different subtypes of siv (h1n1, h3n2, and h1n2) were obviously killed by apoptosis, not necrosis. siv infection in pk-15 and hela cells was shown to ...	2006	16520548
molecular changes associated with adaptation of human influenza a virus in embryonated chicken eggs.	failure to isolate a/fujian/411/2002 (h3n2) in embryonated chicken eggs resulted in its absence from the 2003/2004 vaccine. we analyzed the adaptation of this virus in eggs during serial passages in the amniotic then allantoic cavities. amniotic passage allowed the virus to grow in the allantoic cavity. during adaptation, 6 amino acid substitutions occurred: 4 in ha (g186v, s219f, v226i, v309i) and 2 in na (e119q, q136k). these substitutions allowed binding to saalpha2,3gal- and saalpha2,6gal-co ...	2006	16545416
comparison between denaturing gradient gel electrophoresis and phylogenetic analysis for characterization of a/h3n2 influenza samples detected during the 1999-2004 epidemics in brazil.	in a preliminary study, a denaturing gradient gel electrophoresis method (dgge) was described for influenza virus variants screening [motta, f.c., rosado, a.s., couceiro, j.n.s.s., 2002. standardization of denaturing gradient gel electrophoresis for mutant screening of influenza a (h3n2) virus samples. j. virol. meth. 105, 105-115]. such a protocol has confirmed its usefulness, discriminating closely related samples by the evaluation of the ha1 portion of haemagglutinin coding rna segment. in th ...	2006	16581139
a recombinant pseudorabies virus encoding the ha gene from h3n2 subtype swine influenza virus protects mice from virulent challenge.	the hemagglutinin (ha) gene of a/swine/inner mogolian/547/2001 (h3n2) swine influenza virus (siv) was recombined into the genome of pseudorabies virus (prv) bartha-k61 vaccine strain, generating a recombinant prv expressing the ha gene, designated as rprv-ha. one group of 15 mice was inoculated intranasally (i.n.) with 10(5.0) pfu of rprv-ha, and another two control groups of mice (15 mice per group) were mock-inoculated or inoculated with bartha-k61. mice inoculated with rprv-ha developed hemag ...	2006	16621018
interfering vaccine (defective interfering influenza a virus) protects ferrets from influenza, and allows them to develop solid immunity to reinfection.	defective interfering (di) virus rnas result from major deletions in full-length viral rnas that occur spontaneously during de novo rna synthesis. these rnas are packaged into virions that are by definition non-infectious, and are delivered to cells normally targeted by the virion. di rnas can only replicate with the aid of a coinfecting infectious helper virus, but the small size of di rna allows more copies of it to be made than of its full-length counterpart, so the cell produces defective vi ...	2006	16621180
bacterial sinusitis and otitis media following influenza virus infection in ferrets.	streptococcus pneumoniae is the leading cause of otitis media, sinusitis, and pneumonia. many of these infections result from antecedent influenza virus infections. in this study we sought to determine whether the frequency and character of secondary pneumococcal infections differed depending on the strain of influenza virus that preceded bacterial challenge. in young ferrets infected with influenza virus and then challenged with pneumococcus, influenza viruses of any subtype increased bacterial ...	2006	16622191
influenza surveillance in victoria, 2005.	influenza activity remained within normal seasonal activity with a well-defined peak at week 29 (beginning 18 july) during the victorian influenza season from may to september 2005. surveillance was based on sentinel general practice influenza-like illness (ili) notifications with laboratory confirmation, medical locum service ili notifications and laboratory notification of influenza detections. one thousand and eighty-seven consultations for ili were reported from 38 general practices, while m ...	2006	16637243
phase i evaluation of intranasal trivalent inactivated influenza vaccine with nontoxigenic escherichia coli enterotoxin and novel biovector as mucosal adjuvants, using adult volunteers.	trivalent influenza virus a/duck/singapore (h5n3), a/panama (h3n2), and b/guandong vaccine preparations were used in a randomized, controlled, dose-ranging phase i study. the vaccines were prepared from highly purified hemagglutinin and neuraminidase from influenza viruses propagated in embryonated chicken eggs and inactivated with formaldehyde. we assigned 100 participants to six vaccine groups, as follows. three intranasally vaccinated groups received 7.5-microg doses of hemagglutinin from eac ...	2006	16641287
isolation and genetic characterization of new reassortant h3n1 swine influenza virus from pigs in the midwestern united states.	since the introduction of h3n2 swine influenza viruses (sivs) into u.s. swine in 1998, h1n2 and h1n1 reassortant viruses have emerged from reassortment between classical h1n1 and h3n2 viruses. in 2004, a new reassortant h3n1 virus (a/swine/minnesota/00395/2004) was identified from coughing pigs. phylogenetic analyses revealed a hemagglutinin segment similar to those of contemporary cluster iii h3n2 sivs and a neuraminidase sequence of contemporary h1n1 origin. the internal genes were of swine, h ...	2006	16641303
t cell responses are better correlates of vaccine protection in the elderly.	it is commonly held that increased risk of influenza in the elderly is due to a decline in the ab response to influenza vaccination. this study prospectively evaluated the relationship between the development of influenza illness, and serum ab titers and ex vivo cellular immune responses to influenza vaccination in community dwelling older adults including those with congestive heart failure (chf). adults age 60 years and older (90 subjects), and 10 healthy young adult controls received the 2003 ...	2006	16670345
evidence of the concurrent circulation of h1n2, h1n1 and h3n2 influenza a viruses in densely populated pig areas in spain.	this paper reports on a serological and virological survey for swine influenza virus (siv) in densely populated pig areas in spain. the survey was undertaken to examine whether the h1n2 siv subtype circulates in pigs in these areas, as in other european regions. six hundred sow sera from 100 unvaccinated breeding herds across northern and eastern spain were examined using haemagglutination inhibition (hi) tests against h1n1, h3n2 and h1n2 siv subtypes. additionally, 225 lung samples from pigs wi ...	2006	15914047
immunization with influenza a np-expressing vaccinia virus recombinant protects mice against experimental infection with human and avian influenza viruses.	two-fold immunization of balb/c mice with a vaccinia virus recombinant expressing the np protein of influenza a/pr8/34 (h1n1) virus under the control of a strong synthetic promoter induced specific antibodies and protected animals against low-dose challenge by mouse-adapted heterosubtypic variants of human a/aichi2/68 (h3n2) and avian a/mallard/pennsylvania/10218/84 (h5n2) influenza virus strains. the surviving immunized animals had lower anti-hemagglutinin antibody titers compared to non-immuni ...	2006	16292596
interaction between a 1998 human influenza virus n2 neuraminidase and monoclonal antibody mem5.	influenza virus constantly escapes antibody inhibition by introducing mutations that disrupt protein-protein interactions. based on the structure of the complex between neuraminidase (na) of influenza a/memphis/31/98 (h3n2) and the fab of a monoclonal antibody (mem5) that binds and inhibits the memphis/98 na, we investigated the contribution made by individual amino acids of na to the stability of the complex. we made mutations d147a, d147n, h150a, h197a, d198a, d198n, e199a, e199q, k221r, a246k ...	2006	16297424
low growth ability of recent influenza clinical isolates in mdck cells is due to their low receptor binding affinities.	madin darby canine kidney (mdck) cells have generally been used to isolate influenza viruses from patients. however, in recent years, most fresh isolates of the h3n2 subtype have shown poor growth in mdck cell cultures. such low-growth viruses were often converted to high-growth viruses after several passages through mdck cell cultures. in the present study, viruses were found to lose a potential glycosylation site near the receptor-binding pocket of hemagglutinin (ha), at the same time as they ...	2006	16300986
detailed analysis of the genetic evolution of influenza virus during the course of an epidemic.	the genetic variability of influenza virus is usually studied with sequences selected over numerous years and countries, and rarely within a single season. here we examined the viral evolution and the correlation between genetic and clinical features during an epidemic. from a french prospective household-based study in 1999-2000, 99 infected patients were randomly selected. the ha1 genomic domain was sequenced. phylogenetic analysis showed the existence of two groups of a/h3n2 viruses. we found ...	2006	16316493
safety and efficacy of influenza vaccination in systemic lupus erythematosus patients with quiescent disease.	to assess the safety and efficacy of influenza vaccination in patients with systemic lupus erythematosus (sle), and to evaluate the influence of immunosuppressive drugs on the immune response.	2006	16322083
are swine workers in the united states at increased risk of infection with zoonotic influenza virus?	pandemic influenza strains originate in nonhuman species. pigs have an important role in interspecies transmission of the virus. we examined multiple swine-exposed human populations in the nation's number 1 swine-producing state for evidence of previous swine influenza virus infection.	2006	16323086
anti-influenza virus activity of peramivir in mice with single intramuscular injection.	in the event of an influenza outbreak, antivirals including the neuraminidase (na) inhibitors, peramivir, oseltamivir, and zanamivir may provide valuable benefit when vaccine production is delayed, limited, or cannot be used. here we demonstrate the efficacy of a single intramuscular injection of peramivir in the mouse influenza model. peramivir potently inhibits the neuraminidase enzyme n9 from h1n9 virus in vitro with a 50% inhibitory concentration (ic(50)) of 1.3+/-0.4 nm. on-site dissociatio ...	2006	16325932
[surveillance for influenza a virus infections in infants and young children in beijing, china, 2001-2005].	to characterize the prevalence and antigenic drift of influenza a viruses isolated during the period from 2001 to 2005 in infants and young children in beijing.	2006	17044978
dose-related safety and immunogenicity of baculovirus-expressed trivalent influenza vaccine: a double-blind, controlled trial in adult patients with non-hodgkin b cell lymphoma.	in 27 patients randomized to receive commercial trivalent influenza vaccine (tiv) containing 15 microg of the hemagglutinin (ha) of influenza a (h3n2 and h1n1) and b virus or a recombinant vaccine (rhao) containing 15, 45, or 135 microg of each ha, reactogenicity was minor. among patients with similar prevaccination titers, 40% given 45 microg and 60% given 135 microg of rhao developed an increase in influenza a/h3 neutralizing antibody levels; there were no increases in 4 given tiv. for each va ...	2006	17054068
outbreak of influenza amongst residential school students in malaysia.	in the months of july and august 2003, an outbreak of acute respiratory illness caused by influenza a virus occurred among students in seven residential schools situated in the northern part (perak) of peninsular malaysia. out of 4989 students, aged 13 to 18 years (mean = 15.9), 1419 (28%) were effected by influenza-like illness. all patients were treated as outpatients except for 36 students who required admission for high fever, severe coughing and shortness of breath. abnormal chest x-ray fin ...	2006	16898307
superior relative efficacy of live attenuated influenza vaccine compared with inactivated influenza vaccine in young children with recurrent respiratory tract infections.	young children have a high incidence of influenza and influenza-related complications. this study compared the efficacy and safety of cold-adapted influenza vaccine, trivalent (caiv-t) with trivalent inactivated influenza vaccine (tiv) in young children with a history of recurrent respiratory tract infections (rtis).	2006	17006279
[an adult case of acute cerebellitis after influenza a infection with a cerebellar corical lesion on mri].	we report an adult case of acute cerebellitis associated with influenza a. a 25-year-old woman with fever and headache was diagnosed as having influenza a infection, because nasal swab extract was found positive in the influenza assay. she was treated with oseltamivir. after the treatment, she gradually developed gait and speech disturbance. neurological examination revealed dysarthria with scanning slurred speech, and limb and truncal ataxia. cerebrospinal fluid showed pleocytosis and a four-fo ...	2006	17061703
long intervals of stasis punctuated by bursts of positive selection in the seasonal evolution of influenza a virus.	the interpandemic evolution of the influenza a virus hemagglutinin (ha) protein is commonly considered a paragon of rapid evolutionary change under positive selection in which amino acid replacements are fixed by virtue of their effect on antigenicity, enabling the virus to evade immune surveillance.	2006	17067369
[avian influenza viruses--new causative agents of human infections].	introduction: influenza a viruses can infect humans, some mammals and especially birds. subtypes of human influenza a viruses: a(h1n1), a(h2n2) and a(h3n2) have caused pandemics. avian influenza viruses vary owing to their 15 hemagglutinins (h) and 9 neuraminidases (n). human cases of avian influenza a: in the netherlands in 2003, there were 83 human cases of influenza a (h7n7). in 1997, 18 cases of h5n1 influenza a, of whom 6 died, were found among residents of hong kong. in 2004, 34 human case ...	2006	17068888
response to influenza vaccine in people with non-protective hi antibody titers.	the purpose of the study was to determine which factors correlate directly with response to vaccination in such a group of subjects with non-protective hi antibody titers before vaccination. two vaccines were used, a subunit virus vaccine adjuvanted with mf59 and a split virus vaccine. the analysis indicated that immunization with vaccine adjuvanted with mf59 was an independent variable for immune response against a/h3n2 (or: 3.51; 95% ci: 1.81-6.79) and b (or: 2.31; 95% ci: 1.37-3.89). the resu ...	2006	17082899
[peptide mapping of the monoclonal antibodies against the heavy chain hemagglutinin from influenza virus h3n2].	interaction of the synthetic peptides corresponding to the regions 122-133, 136-147, 154-164 and 314-328 of the virus a/aichi/2/68 hemagglutinin heavy chain with monoclonal antibodies specific for this hemagglutinin was assayed in a variety of tests, e.g., elisa, competition ria, hemagglutinin-inhibition and virus-neutralization assays. the monoclonal antibody 152 reacted with the area 136-147 (epitope a), three monoclonal antibodies 3, 19 and 63 reacted exclusively with the area (154-164) glu ( ...	2006	17094654
subtyping of influenza a isolates in taiwan--2003 to 2004.	some isolated influenza strains are untypable. the possibility that a novel and potentially lethal strain, such as h5 virus, might be one of these untypable strains remains a major concern. this study investigated the nature of untypable influenza strains in taiwan.	2006	17098691
virus associated hemophagocytic syndrome accompanied by acute respiratory failure caused by influenza a (h3n2).	a 40-year-old japanese woman was admitted to oita university hospital with progressive dyspnea, consciousness disturbance and severe cytopenias. her chest roentgenogram showed diffuse bilateral infiltrates. she was therefore forced to receive mechanical ventilation. bone marrow aspiration disclosed numerous hemophagocytic histiocytes, thus suggesting her condition to be hemophagocytic syndrome. in addition, she also developed myocarditis and renal failure. pulsed methylprednisolone, gamma-globul ...	2006	17106167
characterization of multidrug-resistant influenza a/h3n2 viruses shed during 1 year by an immunocompromised child.	development of influenza drug resistance is an important problem in immunocompromised children that could result in treatment failure and viral transmission to others.	2006	17109288
using sentinel surveillance to monitor effectiveness of influenza vaccine is feasible: a pilot study in denmark.	the influenza vaccine for the season 2003/04 did not contain the circulating a(h3n2)/fujian virus strain. vaccine effectiveness (ve) estimates were needed but unavailable. we explored whether or not laboratory based influenza surveillance can be used to estimate ve. we carried out a case-control study nested within danish sentinel surveillance. a case was defined as a person aged 25 or above with a(h3n2)/fujian/411/02 influenza. four controls per case, matched on age groups and time, were select ...	2006	17130655
proteinase inhibitors from streptomyces with antiviral activity.	an extensive screening study for the production of proteolytic inhibitors has been carried out on 75 streptomyces strains. it was found that 18 of the strains and/or their variants (24%) produced proteinaceous substances, which belonged to the group of typical serine protease inhibitors. 23 samples were tested for inhibitory activity on the replication of influenza virus a/germany/34, strain rostock (h7n1) (a/rostock) in chicken embryonic fibroblast (cef) cells. eleven of the tested samples (52. ...	2006	17139614
stochastic processes are key determinants of short-term evolution in influenza a virus.	understanding the evolutionary dynamics of influenza a virus is central to its surveillance and control. while immune-driven antigenic drift is a key determinant of viral evolution across epidemic seasons, the evolutionary processes shaping influenza virus diversity within seasons are less clear. here we show with a phylogenetic analysis of 413 complete genomes of human h3n2 influenza a viruses collected between 1997 and 2005 from new york state, united states, that genetic diversity is both abu ...	2006	17140286
influenza virus pleiomorphy characterized by cryoelectron tomography.	influenza virus remains a global health threat, with millions of infections annually and the impending threat that a strain of avian influenza may develop into a human pandemic. despite its importance as a pathogen, little is known about the virus structure, in part because of its intrinsic structural variability (pleiomorphy): the primary distinction is between spherical and elongated particles, but both vary in size. pleiomorphy has thwarted structural analysis by image reconstruction of elect ...	2006	17146053
antiviral management of seasonal and pandemic influenza.	the goals of antiviral treatment for influenza are to decrease symptoms and functional disability and, more important, to decrease associated complications, hospitalizations, and mortality. four drugs have been approved for treatment of and prophylaxis against influenza in the united states, but they are underutilized. the m2 ion channel inhibitors amantadine and rimantadine are effective for prophylaxis, and they decrease the duration of symptoms if they are used for early treatment of influenz ...	2006	17163384
longitudinal analysis of genotype distribution of influenza a virus from 2003 to 2005.	influenza a viruses cause yearly epidemics, in part, due to their ability to overcome immunity from previous infections through acquisition of mutations. amino acid sequences encoded by genes 4 (ha), 6 (na), 7 (m), and 8 (ns) from 77 h3n2 influenza a isolates, collected between november 2003 and march 2005, were analyzed to determine the extent to which the viruses mutated within epidemic periods and between the epidemics. nucleotide and amino acid sequences were stable throughout the epidemics ...	2006	17021086
reassortment between human a(h3n2) viruses is an important evolutionary mechanism.	phylogenetic relationships of whole genomes of h3n2 viruses circulating in germany during a 6-year period from 1998 to 2005 revealed the co-circulation of different lineages of viruses. multiple reassortment events occurred during this time between viruses belonging to different lineages or different subgroups. strains isolated during 1998-1999 were characterised by a surprisingly high heterogeneity and multiple reassortment events. seventy percent of the examined 1998-1999 viruses had completel ...	2006	17030498
[expression of host genes in influenza virus infected cells].	when nci-h292 human bronchial epithelial cells were infected with influenza a/udorn/72(h3n2) virus, 152 host genes were identified as virus-stimulated genes (vsgs). the expression of these genes was increased more than 4-fold by the virus infection and reached to the level of more than one copy per cell. seventy-three vsgs were also stimulated by interferon-beta (ifn-beta) treatment and they contained the genes known to possess antiviral activity. as a likely consequence, the production of proge ...	2006	17037354
prevention of antigenically drifted influenza by inactivated and live attenuated vaccines.	the efficacy of influenza vaccines may decline during years when the circulating viruses have antigenically drifted from those included in the vaccine.	2006	17167134
[influenza associated excess mortality in argentina: 1992-2002].	to describe the effect of influenza on mortality in argentina, from 1992 to 2002.	2006	17186076
[the properties of the epidemic influenza viruses a and b strains circulating in russia in the 2004-2005 epidemic season].	the epidemic upsurge of influenza morbidity in russia in 2004-2005 was caused by the active circulation of influenza a(h3n2) and b viruses. a hundred and sixty-six epidemic strains were studied. all the strains were isolated in the mck cell culture. influenza a(h3n2) viruses (n=77) were antigenic variants of the reference a/fujian/411/ 2002 and a/california/7/2004 strains. three influenza a(h1n1) viral strains that were antigenic variants of a/new caledonia/20/99 strains were isolated in sporadi ...	2006	17214079
[sequence analysis of the ha1 regions of hemagglutinin genes of influenza viruses (h3n2) isolated from children in beijing from 1998 - 2004].	to characterize the ha1 regions of hemagglutinin gene of influenza viruses (h3n2) isolated from children in beijing from 1998 - 2004.	2006	16792896
amantadine resistance among porcine h1n1, h1n2, and h3n2 influenza a viruses isolated in germany between 1981 and 2001.	this study was designed to gain insight into amantadine susceptibility of porcine influenza a viruses isolated in germany between 1981 and 2001. the 12 studied h1n1, h1n2, and h3n2 porcine influenza virus strains were isolated in chicken eggs and passaged once in mdck cells. plaque reduction assays were applied to examine virus susceptibility to amantadine. genotyping was used to confirm drug resistance. in the results of these antiviral studies, only 3 of the 12 isolates were shown to be amanta ...	2006	16809934
single amino acid substitutions in the hemagglutinin of influenza a/singapore/21/04 (h3n2) increase virus growth in embryonated chicken eggs.	most of the recently circulating h3n2 influenza a strains do not replicate well in embryonated chicken eggs and had to be isolated by cell culture, which presents a great challenge for influenza vaccine production using embryonated chicken eggs. we previously reported that a human h3n2 virus, a/fujian/411/02, which replicates poorly in eggs, could be improved by changing a minimum of two ha residues (g186v/v226i or h183l/v226a). here, we extended our work to the a/singapore/21/04 strain that was ...	2006	16814431
[adamantane resistance among influenza a (h3n2) viruses isolated from the mainland of china].	to study the incidence of adamantane resistance among influenza a (h3n2) viruses isolated from the mainland of china since 1989 through our influenza surveillance system, and to provide more information for the clinical usage of adamantane drugs.	2006	16816855
natural selection on the influenza virus genome.	influenza viruses are the etiological agents of influenza. although vaccines and drugs are available for the prophylaxis and treatment of influenza virus infections, the generation of escape mutants has been reported. to develop vaccines and drugs that are less susceptible to the generation of escape mutants, it is important to understand the evolutionary mechanisms of the viruses. here natural selection operating on all the proteins encoded by the h3n2 human influenza a virus genome was inferre ...	2006	16818477
identification of genetic diversity by cultivating influenza a(h3n2) virus in vitro in the presence of post-infection sera from small children.	antigenic variants probably arise in the field by escaping herd immunity. we have earlier found that sera from small children are more strain-specific than sera from adults and could therefore, provide favourable conditions for selecting antigenic escape mutants. we had access to small volumes of anonymous sera collected in norway after the epidemic season 1999/00, which was dominated by the a/panama/2007/99 (h3n2) variant. the ha gene of the representative strain of that season was genetically ...	2006	16844271
genomic analysis of influenza a viruses, including avian flu (h5n1) strains.	this study was designed to conduct genomic analysis in two steps, such as the overall relative synonymous codon usage (rscu) analysis of the five virus species in the orthomyxoviridae family, and more intensive pattern analysis of the four subtypes of influenza a virus (h1n1, h2n2, h3n2, and h5n1) which were isolated from human population. all the subtypes were categorized by their isolated regions, including asia, europe, and africa, and most of the synonymous codon usage patterns were analyzed ...	2006	16858618
evidence of a cross-protective immune response to influenza a in the cotton rat model.	epidemiologic evidence suggests that cross-protective immune responses to influenza a viruses that have different hemagglutinin and neuraminidase subtypes occur in humans. this study characterized this heterosubtypic immunity in cotton rats (sigmodon hispidus). animals were infected with influenza a/pr/8/34 (h1n1) or a/wuhan/359/95 (h3n2), and then challenged with a/wuhan/359/95(h3n2) virus 4 weeks later. viral titers, respiratory rates, and pathology of the respiratory tract following primary a ...	2006	16860444
infection of human airway epithelium by human and avian strains of influenza a virus.	we describe the characterization of influenza a virus infection of an established in vitro model of human pseudostratified mucociliary airway epithelium (hae). sialic acid receptors for both human and avian viruses, alpha-2,6- and alpha-2,3-linked sialic acids, respectively, were detected on the hae cell surface, and their distribution accurately reflected that in human tracheobronchial tissue. nonciliated cells present a higher proportion of alpha-2,6-linked sialic acid, while ciliated cells po ...	2006	16873262
prevention and control of influenza: recommendations of the advisory committee on immunization practices (acip).	this report updates the 2005 recommendations by the advisory committee on immunization practices (acip) regarding the use of influenza vaccine and antiviral agents (cdc. prevention and control of influenza: recommendations of the advisory committee on immunization practices [acip]. mmwr 2005;54[no. rr-8]:1--44). the 2006 recommendations include new and updated information. principal changes include 1) recommending vaccination of children aged 24-59 months and their household contacts and out-of- ...	2006	16874296
influenza-related mortality in the italian elderly: no decline associated with increasing vaccination coverage.	we investigated trends in influenza-related mortality among the elderly population in italy associated with increased vaccination coverage. using italian vital statistics data, we studied monthly death rates for pneumonia and influenza and all-cause for persons >/=65 years of age by 5-year age groups for 1970-2001. using a classic seasonal regression modelling approach, we estimated the age-specific seasonal excess mortality rates among italian elderly as a measure of influenza-related deaths. w ...	2006	16876293
lack of transmission of h5n1 avian-human reassortant influenza viruses in a ferret model.	avian influenza a h5n1 viruses continue to spread globally among birds, resulting in occasional transmission of virus from infected poultry to humans. probable human-to-human transmission has been documented rarely, but h5n1 viruses have not yet acquired the ability to transmit efficiently among humans, an essential property of a pandemic virus. the pandemics of 1957 and 1968 were caused by avian-human reassortant influenza viruses that had acquired human virus-like receptor binding properties. ...	2006	16880383