The clinical impact of human cytomegalovirus (CMV) and progression to CMV disease in immunocompromised patients has been reduced by therapeutic strategies using ganciclovir, valganciclovir, foscarnet and cidofovir. However, extensive antiviral therapy increases the risk of antiviral resistance due to mutations in the UL97 protein kinase and UL54 DNA polymerase. Co-infection with HHV-6 or HHV-7 is also associated with increased CMV reactivation and disease. Genotypic CMV antiviral resistance was identified in 38% of Australian immunocompromised patients. While UL97 mutations only were identified in 23% of patients, additional UL54 mutations, with the potential to confer multidrug resistance, were detected in 15% of patients. Antiviral resistant CMV strains were found to emerge rapidly in highly immunocompromised patients, and some strains were able to persist in the absence of selective pressure. Three new mutations were identified (UL97 - N597D, UL54 - F412S, D485N). N597D was characterised by recombinant phenotyping and conferred minimal ganciclovir resistance. Neither baculovirus nor coupled transcription/translation yielded full-length UL54 protein (pUL54; ~140 kDa) for activity assays. However, truncated pUL54 (~66 kDa) was purified after prokaryotic expression. HHV-6 and HHV-7 co-infection was a common clinical occurrence; with 36% of liver transplant recipients infected with HHV-6 (11% persistent) and 80% with HHV-7 (52% persistent). ValGCV therapy did not significantly alter the incidence of HHV-6, HHV-7 or co-infection. The most prevalent co-infection pattern was CMV, HHV-6 and HHV-7 (46%) and both CMV and HHV-7 (38%). CMV reactivation was predominantly independent of HHV-6/HHV-7, although 27% of patients had initial HHV-7 reactivation. Despite frequent co-infection, HHV-6 and HHV-7 were not associated with clinical disease, with possible exception of HHV-7 and acute cellular rejection. CMV antiviral resistance remains a significant issue in transplantation, emphasising the importance of antiviral resistance testing in an era of widespread prophylaxis. New mutations in UL97 and UL54 continue to be identified. Further characterisation of UL54 mutations using polymerase activity assays would increase our knowledge of enzymological basis of antiviral resistance. Co-infection with HHV-6 and HHV-7 is common in transplant recipients, but does not play a significant role in disease. Similar co-infection rates between valGCV-treated and untreated patients indicate that valGCV is not highly effective against HHV-6 and HHV-7.

The detection of immunostimulatory DNA is well documented to occur at several cellular sites, but there is limited evidence of nuclear innate DNA sensing. Prior to this study, the detection of herpesviral DNA was thought to be restricted to the cytosol so as to limit the sensing of host DNA in the nucleus. However, given the nuclear lifecycle of these viruses, we hypothesized that viral DNA could be sensed in the nucleus of infected cells. To test this hypothesis we examined the activation of interferon regulatory factor 3 (IRF-3) in response to herpes simplex virus 1 (HSV-1) infection of primary human foreskin fibroblasts (HFF). Using a mutant defective for expression of all viral genes, we observed that the release of viral DNA into the nucleus is necessary to activate IRF-3 signaling. Furthermore, we determined this response to be dependent on nuclear-localized interferon inducible protein 16 (IFI16) and the cytoplasmic stimulator of interferon genes (STING) adaptor protein.

<p>U radu je ispitana zastupljenost influenca A virusa, njihova antigenska i genetička svojstva i osetljivost na antivirotik oseltamivir.</p><p>Ispitivanje je sprovedeno u toku četiri uzastopne sezone, od 2010/2011 do 2013/2014 &nbsp;i obuhvatilo je 887 briseva nosa i grla pacijenata sa simptomima gripa, sa teritorije Južnobačkog okruga. Svi uzorci su&nbsp;testirani na prisustvo influenca A(H1N1)pdm09, A(H3N2), A(H1N1), A(H5) i A(H7) i influenca B virusa, real-time RT PCR testom. Pozitivni uzorci iz sezona 2012/2013 i 2013/2014, podvrgnuti su izolaciji na MDCK ćelijskim kulturama, a zatim je izvr&scaron;eno ispitivanje sposobnosti dobijenih izolata da aglutiniraju eritrocite koko&scaron;ke, čoveka i zamorca u reakciji virusne hemaglutinacije. Antigenska svojstva izolata sa hemaglutinacionim titrom &ge;40, ispitana su reakcijom inhibicije hemaglutinacije. Genetičkoj karakterizaciji, sekvenciranjem hemaglutinin i neuraminidaza gena, podvrgnuti su reprezentativni izolati iz sezona 2012/2013 i 2013/2014. Za ispitivanje osetljivosti odabranih izolata virusa na oseltamivir upotrebljen je hemiluminiscentni test inhibicije aktivnosti neuraminidaze.</p><p>Ukupno 46,3% (411/887) uzoraka bilo je influenca pozitivno, od čega je 73% (300/411) bilo influenca A pozitivno, a 27% (111/411)influenca B pozitivno (p&lt;0,0001). &nbsp;Influenca A(H1N1)pdm09 podtip je detektovan u 48% (144/300), a A(H3N2) podtip u&nbsp;52% (156/300) influenca Apozitivnih uzoraka. Najveći procenat influencaA pozitivnih zabeležen je u uzrastnoj grupi 5-14 godina (48,2%, 77/160) i kod pacijenata sa lak&scaron;im kliničkim manifestacijama gripa (43,7%, 153/350).</p><p>Influenca A(H1N1)pdm09 podtip preovladavao je u uzrastnoj grupi 15-29 godina (66%, 31/47, p=0,0400) i 30-64 godina (55,9%,71/127, p=0,0215), kao i kod pacijenata sa te&scaron;kom akutnom respiratornom bole&scaron;ću (63,5%, 80/126, p&lt;0,0001), fatalnih slučajeva (100%,9/9, p=0,0039) i pacijenata sa hroničnim bolestima i stanjima (68,8%, 84/122, p&lt;0,0001).&nbsp;</p><p>Influenca A(H3N2) podtip dominirao je kod dece uzrasta do 4 godine (72,2%,13/18, p=0,0381) i 5-14 godina (75,3%, 58/77, p&lt;0,0001), kod pacijenata sa lak&scaron;im oblikom bolesti (69,3%,106/153, p&lt;0,0001) i bez hroničnih bolesti ili stanja (66,3%, 118/178,&nbsp;p&lt;0,0001).</p><p>Najznačajniji predikcioni faktori komplikacija influence bili su: prisustvo hroničnih bolesti ili stanja i uzrast &ge;15 godina. Prisustvo hroničnih bolesti ili stanja nosilo je 34 puta, a uzrast &ge;15 godina 10 puta veći rizik od nastanka te&scaron;kih oblika bolesti.</p><p>Izolacija influenca virusa na MDCK ćelijskim kulturama, bila je uspe&scaron;na u 34,3% (70/204) slučajeva, pri čemu je u grupi uzoraka sa real-time RT-PCR Ct vrednostima &lt;30 ona iznosila 80,5% (62/77), kod uzoraka sa Ct vrednostima 30-34 svega 8,7% (8/92), a izolacija iz uzoraka sa Ct vrednostima &gt;34 nije bila moguća. U reakciji hemaglutinacije, najbolji rezultati su postignuti sa eritrocitima zamorca, koje je u titru &ge;40 aglutiniralo 56% (14/25) A(H1N1)pdm09 virusa i 62,5% (15/24) A(H3N2) virusa. Sa humanim eritrocitima dobar titar dalo je 16% (4/25) influenca A(H1N1)pdm09 i 8,3% (2/24) A(H3N2) virusa, a sa koko&scaron;ijim eritrocitima 8% (2/25) A(H1N1)pdm09 virusa i nijedan virus A(H3N2) podtipa.</p><p>Rezultati antigenske karakterizacije pokazali su da je svih 23 influenca virusa A(H1N1)pdm09 podtipa, iz sezona 2012/2013 i 2013/2014, antigenski bilo slično referentnom, vakcinalnom virusu A/California/7/2009. Nasuprot tome, samo 1 od 7 ispitanih A(H3N2) virusa iz sezone 2012/2013, antigenski je bio sličan vakcinalnom virusu A/Victoria/361/2011, a samo 2 od 20 iz sezone 2013/2014 antigenski je bilo slično vakcinalnom A/Texas /50/2012 virusu.</p><p>Filogenetska analiza hemaglutinin gena influenca A(H1N1)pdm09 virusa iz sezone 2012/2013, pokazala je da su u na&scaron;oj sredini, bili prisutni virusi iz dve različite genogrupe, 6C i 7, dok su naredne sezone svi analizirani virusi pripadali genogrupi 6B. Virusi iz na&scaron;e sredine bili su filogenetski srodni A(H1N1)pdm09 virusima iz drugih evropskih zemalja. Svi ispitani A(H3N2) virusi iz sezone 2012/2013 i2013/2014, pripadali su genetičkoj grupi&nbsp; 3C.3.Filogenetski su bili srodni sa virusima iz drugih gografskih regiona Evrope.</p><p>Svih 20 izolata influenca A(H1N1)pdm09 podtipa i 23 A(H3N2) podtipa pokazali su normalnu inhibiciju aktivnosti neuraminidaze pod dejstvom oseltamivira.ekvenciranje neuraminidaza gena jednog A(H3N2) virusa, koji je imao 8 puta redukovanu inhibiciju aktivnosti neuraminidaze oseltamivirom, ukazalo jena prisustvo retke mutacije Q391H, povezane sa rezistencijom na inhibitore neuraminidaze.</p><p>Rezultati ovog rada ukazali su na značaj influenca A virusa kao etiolo&scaron;kih uzročnika akutnih respiratornih obolenja u na&scaron;oj sredini, naročito za osobe sa hroničnim bolestima koje su pod povećanim rizikom od razvoja te&scaron;kih oblika gripa. U ovom istraživanju stečena su i saznanja koja imaju praktičnu primenu u postupku antigenske karakterizacije influenca A virusa, koja je jedna od ključnih faza u procesu pripreme vakcine protiv gripa. Značajna antigenska razlika A(H3N2) virusa koji su cirkulisali u sezonama 2012/2013 i 2013/2014 u odnosu na viruse koji su bili u sastavu vakcina u datim sezonama, ukazala je na neophodnost unapređenja proizvodnje vakcine protiv gripa. Dobijeni su i prvipodaci orezistenciji na antivirotik oseltamivir, kao i o filogenetskim odnosima i genetičkim grupama virusa koji su&nbsp; cirkulisali u na&scaron;oj sredini.</p> / <p>In this study we investigated the representation, antigenic and genetic properties, and sensitivity to antiviral drug oseltamivir of influenza A viruses. The study was conducted&nbsp; during 4 consecutiveseasons 2010/2011 - 2013/2014, and included 887 nasal and throat swabs taken from patients with influenza-like symptoms from South&nbsp; Backa district. All samples were tested for influenza A(H1N1)pdm09, A(H3N2), A(H1N1), A(H5), A(H7) and influenza B viruses, by real-time RT-PCR. Isolation on MDCK cell culture was performed with positive samples from seasons 2012/2013 and 2013/2014, and virus isolates were tested for ability&nbsp; to agglutinate guinea pig, chicken and human red blood cells in reaction of virus hemagglutination. Antigenic properties of isolates with hemagglutination titre &ge;40, were investigated using reaction&nbsp; of hemagglutination inhibition. Genetic characterization was performed by sequencing of neuraminidase and hemagglutination genes of representative isolates from seasons 2012/2013 and 2013/2014. Testing for sensitivity to oseltamivir was done with chemiluminescent neuraminidase inhibition assay.</p><p>Total of 46,3% (411/887) of samples were influenza positive, out of which 73% (300/411) were influenza A positive and 27% (111/4111, p&lt;0,0001) were influenza&nbsp; B positive. Influenza A(H1N1)pdm09 subtype was detected in 48% (144/300), and A(H3N2) subtype in 52% (156/300) of influenza A positive samples. The highest proportion of influenza A positive samples wasfound in age group 5-14&nbsp; years (48,2%,&nbsp; 77/160) and among patients with uncomplicated influenza (43,7%, 153/350).</p><p>Influenza A(H1N1)pdm09 subtype predominated in age group 15-29 years (66%, 31/47, p=0,0400) and 30-64 years (55,9%,71/127, p=0,0215), in patients with severe acute respiratory illness (63,5%, 80/126, p&lt;0,0001), in fatal cases (100%, 9/9, p=0,0039), and among patients with underlying chronic diseases and conditions (68,8%,84/122, p&lt;0,0001).</p><p>Influenza A(H3N2) subtype predominated in age group &le;4 years (72,2%, 13/18, p=0,0381) and 5-14 years (75,3%,58/77, p&lt;0,0001), in patients with mild form of influenza (69,3%,106/153, p&lt;0,0001), and in group of patients without chronic diseases and conditions (66,3%,60/478, p&lt;0,0001).</p><p>The most significant risk factors for severe influenza were: the presence of underlying diseases and conditions and age &ge;15 years. Patients with chronic illnesses and conditions had 34 times higher and patients &ge;15 years of age 10 times higher risk from severe influenza.</p><p>Isolation rate of influenza A viruses in MDCK cell cultures was 34,3% (70/204). For samples with real time RT-PCR Ct values &lt;30 isolation rate was 80,5% (62/77), for samples with Ct values 30-34 it was 8,7% (8/92), while isolation of viruses from samples with Ct values &gt;34 was not successful. In the reaction of virus hemagglutination, the best results were achieved with guinea pig red blood cells which agglutinated in titre &ge;40, 56% (14/25) of influenza A(H1N1)pdm09 viruses and&nbsp; 62,5% (15/24) of A(H3N2) viruses. With human erythrocytes, good titre gave 16% (4/25) of influenza A(H1N1)pdm09 and 8,3% (2/24)of A(H3N2) viruses and with chicken erythrocytes 8% (2/25) A(H1N1)pdm09 viruses and none of the A(H3N2) viruses.</p><p>Results of the antigenic characterization of 23 influenza A(H1N1)pdm09 viruses, showed that they were antigenically similarto referent, vaccine virus A/California/7/2009. On the contrary, only 1 out of 7 influenza A(H3N2) viruses from season 2012/2013,was antigenically similar to A/Victoria/361/2011 vaccine virus, and only 2 out of 20 from season 2013/2014 were antigenically similar to A/Texas/50/2012&nbsp; vaccine virus.</p><p>Filogenetic analysis of hemagglutinin genes indicated co-circulation of 2 distinct genetic groups, 6C and 7, of A(H1N1)pdm09 viruses during the season 2012/2013, while during the season 2013/2014 all tested viruses were from genetic group 6B. Influenza A(H1N1)pdm09 viruses from our region, were closely related to viruses from other European countries. All influenza A(H3N2) viruses from season 2012/2013 and 2013/2014 belonged to genetic clade 3C.3 and were closely related to viruses from different European countries.</p><p>Total of 20 A(H1N1)pdm09 isolates and 23 A(H3N2) isolates were tested for sensitivity to oseltamivir, and all of them showed normal inhibition of neuraminidase activity with oseltamivir. Sequencing of&nbsp; neuraminidase gene of one A(H3N2) virus with 8-fold reduced inhibition by oseltamivir, revealed rare mutation Q391H associated with antiviral resistance.</p><p>Results of this study indicate the significance of influenza A viruses as etiological factors of acute respiratory diseases in our area, especially for persons with chronic medical conditions who are at higher risk for severe influenza. Data gathered during&nbsp;the process of virus isolation and investigation of hemagglutination abilities of&nbsp; isolated viruses, have practical application in antigenic testing of influenza A viruses which is one of the key points of process of anti-flu vaccine production. Significant &nbsp;antigenic difference between influenza A(H3N2) viruses from seasons 2012/2013 and&nbsp; 2013/2014 and vaccine viruses, emphasis the importance of vaccine production improvement. During this study, the first data about antiviral resistance, filogenetic relationships and genetic groups of influenza viruses from our region, were obtained.</p>

A ce jour, les données génétiques et moléculaires se rapportant aux virus influenza de type A (VIs) présents dans la population porcine au Québec sont relativement rares. Pourtant, ces informations sont essentielles pour la compréhension de de l'évolution des VIs à grande échelle de 2011 à 2015. Afin de remédier à ce manque de données, différents échantillons (pulmonaires, salivaires et nasaux) ont été prélevés à partir de 24 foyers dans lesquelles les animaux présentaient des signes cliniques. Ensuite, les souches virales ont été isolées en culture cellulaire (MDCK) ou sur oeufs embryonnés. Les 8 segments génomiques des VIs de 18 souches virales ont par la suite été séquencés et analysés intégralement. La résistance aux drogues antivirales telles que l’oseltamivir (GS4071) carboxylate, le zanamivir (GS167) et l’amantadine hydrochloride a également été évaluée par des tests d'inhibition de la neuraminidase (INAs) ainsi que par un test de réduction sur plaque. Deux sous-types viraux H3N2 et H1N1 ont été identifiés dans la population porcine au Québec. Douze souches des VIs de sous-type trH3N2 ont été génétiquement liées au Cluster IV, avec au moins 6 profils de réassortiment différents. D'autre part, 6 souches virales ont été trouvées génétiquement liées au virus pandémique A(H1N1)pdm09 avec au moins trois profils de réassortiment génétique différents. Le sous-type trH3N2 des VIs est le plus répandu dans la population porcine au Québec (66,7%). La cartographie d'épitope de la protéine HA de sous-type H3 a présenté la plus forte variabilité avec 21 substitutions d’acides aminés sur 5 sites antigéniques A (5), B (8), C (5), D (1), et E (2). Toutefois, la protéine HA du sous-type H1 avait seulement 5 substitutions d'aa sur les 3 sites antigéniques Sb (1), Ca1 (2) et Ca2 (2). Un isolat H1N1 (1/6 = 16,7%) et 1 autre trH3N2 (1/12 = 8,3%) ont été trouvés comme étant résistants à l'oseltamivir. En revanche, 2 isolats du H1N1 (2/6 = 33,3%) et 2 autres du trH3N2 (2/12 = 16,7%) ont révélé être résistants au zanamivir. Dans l'ensemble, le taux de résistance aux INAs et à l’amantadine était compris entre 33,3% et 100%. La présence des VIs résistants aux drogues antivirales chez les porcs ainsi que l'émergence possible de nouvelles souches virales constituent des préoccupations majeures en la santé publique et animale justifiant ainsi la surveillance continue des VIs dans la population porcine au Québec. / Data about genomic variability of swine influenza A viruses (SIV) in Quebec herds are scarce. Yet, this information is important for understanding virus evolution in Quebec from until 2015. Different clinical samples were obtained from 24 outbreaks of swine flu in which animals were experiencing respiratory disease. Samples including lung tissues, saliva and nasal swabs were collected and virus isolation was attempted in MDCK cells and embryonated eggs. All eight gene segments of the 18 isolated SIV strains were sequenced and analysed. Antiviral drugs resistance against oseltamivir carboxylate (GS4071), zanamivir (GS167) and amantadine hydrochloride was evaluated by neuraminidase inhibition assays (NAIs) and plaque reduction assay. Two subtypes of SIV, H3N2 and H1N1, were identified in Quebec pig herds. Twelve SIV strains were genetically related to trH3N2 Cluster IV and at least 6 different reassortment profiles were identified. On the other hand, 6 Quebec SIV strains were found to be genetically related to the pandemic virus A(H1N1)pdm09 and from which three reassortment profiles were identified. Overall, the trH3N2 was the most prevalent subtype (66.7%) found in Quebec swine herds. The epitope mapping of HA indicated that the H3 subtype was the most variable with a possibility of 21 amino acids (aa) substitutions within the 5 antigenic sites A(5), B(8), C(5), D(1) and E(2). However, the HA protein of the H1 subtype had only 5 aa substitutions within 3 antigenic sites Sb(1), Ca1(2) and Ca2(2). One H1N1 (1/6 = 16.7%) and one trH3N2 (1/12 = 8.3%) were identified as strains resistant against oseltamivir. In contrast, two H1N1 (2/6 = 33.3%) and two trH3N2 (2/12 = 16.7%) strains were found to be resistant against zanamivir. Overall, the SIV resistance against antiviral neuraminidase inhibitor drugs was (33.3%). All strains were resistant against the M2 inhibitor antiviral drug, amantadine. The presence of antiviral drug resistance in Quebec swine herds and the possible emergence of new SIVs strains are public health concerns supporting the surveillance of SIVs.