Browsing by Issue Date, starting with "2016-08-24"
Now showing 1 - 5 of 5
Results Per Page
Sort Options
- Influenza seroprotection correlates with predominant circulating viruses during 2014/15 and 2015/16 seasons in PortugalPublication . Guiomar, Raquel; Cristóvão, Paula; Conde, Patrícia; Costa, Inês; Pechirra, Pedro; Rodrigues, Ana Paula; Pereira da Silva, Susana; Nunes, Baltazar; Mouro Pinto, Rita; Sobrinho Simões, Joana; Costa, Maria do Rosário; Guimarães, João Tiago; Rodrigues, Fernando; Correia, Lurdes; Pereira-Vaz, João; Caseiro, Paula; Cabral Veloso, Rita; Mota Vieira, Luísa; Pimentel Couto, Ana Rita; Santos, Margarida; Bruges Armas, Jácome; Branquinho, Paula; Corte-Real, Rita; Martins, Luís; Cunha, Mário; Almeida, Sofia; Viseu, Regina; Inácio, Filipe; Peres, Maria João; Milho, Luís; Fernandes, Aida; Maurílio, Manuel; Caldeira, Filomena; Sanches, Raquel; Dantas, Filipa; Freitas, Ludivina; Andrade, Graça; Mota, PaulaBACKGROUND: Population immune profile for influenza is highly affected by circulating influenza viruses, thus changing the risk of infection for influenza. This study aims to assess influenza immunity in the Portuguese population by age groups, during 2014 and 2015 and establish a relationship between seroprotection and circulating influenza viruses in 2014/15 and 2015/16 seasons. METHODS: Two cross-sectional studies were developed based on a convenience serum sample collected in June 2014 (n=626) and July 2015 (n=675) in hospitals from mainland and Azores and Madeira.Serums equally represent all age groups. Antibody titers were evaluated by HI assay for strains recommended for seasonal influenza vaccine northern hemisphere,2014/15 and 2015/2016. Seroprevalences were estimated for each strain by age group and the association with seasonal cumulative influenza-like illness (ILI) rates for influenza virus during both seasons was analised. RESULTS: In June 2014 the highest seroprotection was observed for influenza A(H3) (39.0%; 95% CI: 36.2-43.8%) and A(H1)pdm09 (29.7; 95% CI: 26.3-33.4%), with higher levels in children 5-14 years old. In 2014/2015 a dominant circulation of influenza B/Yamagata was observed with high incidence rates in individuals under 65 years old, the ones that had lower seroprotection. Although before the start of the season high protection for A(H3) was observed, the circulation of the new drift A(H3) strains had gained an immunological advantage,in accordance with A(H3) elevated incidence rates observed during 2014/15. In July 2015 the highest seroprotection was observed for influenza B/ Yamagata (55.1%; 95% CI: 51.4-58.9%), 2.4 times the estimated 2014.This increase was even more pronounced in younger (≤ 4 years old), 6.3 times increase in 2015.This fact is in agreement with the predominant influenza B virus detected and the high ILI incidence rate observed in children during 2014/2015 epidemic. Seroprotection levels for influenza A in July 2015 were not significantly different from 2014.During 2015/16 season, influenza A(H1N1)pdm09 was predominant, with high incidence rate in < 65 year old. Influenza B/Victoria lineage,although detected at low levels increased in frequency, in agreement with the lowest level of seroprotection detected in the general population before the start of 2015/2016 season (21.8%; 95% CI: 18.7-24.0%). CONCLUSIONS There was a correlation between virus circulation, incidence rates for each age group and the previous seroprotection for seasonal influenza viruses.Our study highlights the value of measuring the serological profile for influenza to establishe risk groups for infection for which an increase preventive measures, including vaccination, should be fostered.
- Influenza severe cases in hospitals, between 2014 and 2016 in PortugalPublication . Guiomar, Raquel; Pechirra, Pedro; Cristóvão, Paula; Costa, Inês; Conde, Patrícia; Corte-Real, Rita; Branquinho, Paula; Silvestre, Maria José; Almeida Santos, Madalena; Fernandes, Isabel; Dias, Isabel; Rodrigues, Sónia; Sena, Nadir; Lazzara, Daniela; Sobrinho Simões, Joana; Costa, Maria do Rosário; Guimarães, João Tiago; Rodrigues, Fernando; Pereira-Vaz, João; Correia, Lurdes; Andrade, Graça; Freitas, Ludivina; Figueira, Neuza; Sanches, Raquel; Marques, Mónica; Barros, Margarida; Mota Vieira, Luísa; Cabral Veloso, Rita; Castelo Branco, Cláudia; Pimentel, Sílvia; Duarte, Joana; Pereirinha, Tânia; Bulhões, Sara; Moniz, Raquel; Brilhante, Maria José; Bruges Armas, Jácome; Pimentel Couto, Ana Rita; Santos, Margarida; Soares, Marta; Melo Cristino, José; Ribeiro, Carlos; Carvalho, Dinah; Barreto, Rosário; Ramos, Maria Helena; Castro, Ana Paula; Matos Santos, Ana Cláudia; Cunha, Mário; Martins, Luís; Almeida, Sofia; Peres, Maria João; Viseu, Regina; Inácio, Filipe; Mota, PaulaBackground: Since 2009, the Portuguese Laboratory Network (PLNID) for Influenza Diagnosis has integrated 15 Laboratories in mainland and Atlantic Islands of Azores and Madeira. This PLNID added an important contribute to the National Influenza Surveillance Program regarding severe and hospitalized influenza cases. The present study aims to describe influenza viruses detected in influenza like illness (ILI) cases: outpatients (Outp), hospitalized (Hosp), and intensive care units (ICU), between 2014 and 2016. Methods: The PLNID performs influenza virus diagnosis by biomolecular methodologies. Weekly reports to the National Influenza Reference Laboratory ILI cases tested for influenza. Reports include data on detecting viruses, hospital assistance, antiviral therapeutics, and information on death outcome. Were reported during two winter seasons 8059 ILI cases,being 3560 cases in 2014/15 (1024 in Outp, 1750 Hosp, and 606 in ICU) and 4499 cases in 2015/2016 (1933 in Outp, 1826 Hosp, and 740 in ICU). Results: The higher percentage of influenza positive cases were detected in Outp in both seasons, 18% during 2014/15 and 20% in 2015/16. In 2014/15,influenza cases were more frequent in individuals older than 65 years old and these required more hospitalizations,even in ICU. In 2015/16,the influenza cases were mainly detected in individuals between 15-64 years old. A higher proportion of influenza positive cases with hospitalization in ICU were observed in adults between 45-64 years old.During the study period,the predominant circulating influenza viruses were different in the two seasons: influenza B and A(H3) co-circulated in 2014/15,and influenza A(H1)pdm09 was predominant during 2015/16. Even when influenza A is notthe dominant virus, A(H3) and A(H1)pdm09 subtypes correlate with higher detection rate in hospitalized cases (Hosp and UCI), with higher frequencies in adults older than 45. Influenza B,detected in higher proportion in outpatients, was frequently relatedwith influenza cases in younger age groups: 0-4 and 5-14 years old. Conclusions: This study highlights the correlation of theinfluenza virus type/subtype that circulates in each season with the possible need for hospitalization and intensive care in special groups of the population. Circulation of influenza A subtypes can cause more frequentdisease in individuals older than 45, with need of hospitalization including intensive care. On the other hand, influenza B is more frequently associated with less severe cases and with infection in children and younger adults. Influenza B circulation might predict lower number of hospitalizations.The identification of influenza type in circulation,byPLNID ineach season, could guide action planning measures in population health care.
- Influenza in pregnant women during 3 seasons, between 2013-2016 in PortugalPublication . Conde, Patrícia; Cristóvão, Paula; Costa, Inês; Pechirra, Pedro; Guiomar, RaquelBackground: Since the 2009 pandemic, pregnant women (PW) have been assumed has a high risk group for increased morbidity and mortality linked to influenza infection. From 2013 to 2016, the Portuguese Influenza Surveillance Programme integrates an obstetric unit network that reports influenza-like illness (ILI) cases and collects nasopharyngeal samples for influenza surveillance and diagnosis. This study aims to characterize cases of influenza infection in pregnant women during 2013-2016 in Portugal. Methods: Between 2013 and 2016, cases of ILI in PW were compared with ILI in childbearing age women (NPW), between 15 and 44 years. In study period were reported 634 ILI cases (220 ILI in 2013/14, 152 in 2014/15 and 262 in 2015/16) of each 149 in PW. Influenza and other respiratory viruses diagnosis were performed by multiplex RT-PCR. Data regarding symptoms, hospitalization, vaccination and antiviral treatment were recorded. Results: During the overall study period the proportion of influenza confirmed cases were similar in PW and NPW, 51% and 54% respectively. The analysis by (sub)type of influenza virus revealed that A(H1)pdm09 season was detected 1.3 times more frequently in PW than in NPW during 2013/14, situation not so evident during 2015/16 season, with low ILI incidence rates. B/Yamagata viruses were identified in PW in a proportion 1.5 times higher than in NPW (2014/15 season). Influenza A(H3) was detected in higher proportion in NPW, 2 to 4 times higher, in 2013/14 and 2014/15 seasons, respectively, when compared with PW. The other respiratory viruses were found in higher percentage among PW, with a positive rate between 55% and 68% during the 3 seasons. RSV, parainfluenza vírus and human metapneumovirus have a higher prevalence in PW, while human rhinovirus reach the higher percentage among NPW. In 660 women ILI cases that reported vaccination status, vaccine coverage was higher in NPW (6.3%;29/463) compared to PW (4.1%;6/143). Vaccine failures were registered in 45% (13/29) cases in NPW and in 67% in PW (4/6). Information on antiviral treatment was reported in 406 ILI cases. Antivirals were prescribed in 8.6% (28/235) of NPW and in 13.6% (11/81) of PW. Were reported 10 PW with need of hospitalization, 6 of these cases positive for influenza A(H1)pdm09 and 1 positive forrhinovirus. None of hospitalized PW were vaccinated. Conclusions: Study shows that PW must still considered a high risk group for influenza and other respiratory viruses infection. Study highlight that influenza A and B presents a higher frequency of infection in PW compared to NPW that might be associated with increased risk for complications. Reinforcement of vaccination campaign will be a challenge in influenza prevention, nevertheless, influenza vaccination is free and highly recommended in Portugal for PW risk group.
- Phylogeny of influenza A(H1)pdm09 viruses, detected in Portugal between 2009 and 2016Publication . Pechirra, Pedro; Cristóvão, Paula; Conde, Patrícia; Costa, Inês; Guiomar, RaquelBackground: Influenza A(H1)pdm09 viruses show a constant antigenic pattern since its emergence in the 2009 pandemics. However, since then, these viruses have been increasing their genetic diversity. This fact supports the need for continuous monitoring of genetic characteristics of influenza A(H1)pdm09 viruses, which can suddenly acquire new antigenic properties or decrease their susceptibility to antiviral drugs. Methods: From the 2009 pandemic until 2016, the Portuguese NIC has detected 1634 influenza A(H1)pdm09 viruses in the scope of the Portuguese Influenza Surveillance Programme. During this period, 586 viruses were isolated and characterised antigenically by HI assays. Genetic characterisation was also performed for 195 viruses by HA1 subunit sequencing. Results: All studied influenza A(H1)pdm09 viruses revealed no antigenic diversity, being antigenically similar to the vaccine strain A/California/7/2009. In the pandemic season viruses belonged to a single genetic group 1 (A/Hong Kong/2212/2010). In the 2010/2011 season, Portuguese pandemic viruses showed some genetic diversity, being distributed by 4 genetic groups (3,4,5, and 6). During these 2 seasons, viruses presented one or two amino acid changes in antigenic sites, comparing to A/California/7/2009 vaccine strain. During 2011-2013, were detected H1 virus from group 7 (A/St. Petersburg/100/2011). Most influenza H1pdm viruses circulating in 2012/2013 belonged to the subgroup 6C (represented by A/Estonia/76677/2013) harbouring 2 amino acid substitutions in antigenic sites of hemagglutinin (S185T and S203T). Since 2013/2014 season, all H1pdm viruses clustered in the subgroup 6B (A/South Africa/3626/2013) and their hemagglutinins fixed 3 amino acid changes located in antigenic sites (K163Q, S185T and S203T). During the last season 2015/2016, within 6B group, new H1pdm viruses have emerged giving rise to a new subgroup represented by the strain A/New York/61/2015 (6B.1). Most 2015/2016 viruses present an additional amino acid substitution in HA antigenic sites comparing with the vaccine strain: S71P in 6B group and S162N in 6B.1 subgroup. Conclusions: Most influenza A(H1)pdm09 viruses, since its emergence until today, remain antigenically similar to the H1 vaccine strain - A/California/7/2009. However, over the last 7 seasons, these viruses have diversified into different genetic groups. As expected, is also observed the fixation of an increasing number of amino acid substitutions in antigenic sites. The genetic characterisation, in the scope of virological surveillance of influenza, is crucial to understand possible pathways of evolution and antigenic drift of these viruses.
- Influenza A(H3) whole genome analysis: searching causes for vaccine failure in 2011/2012Publication . Pechirra, Pedro; Maia, Ana Carina; Sampaio, Daniel Ataíde; Borges, Vítor; Gomes, João Paulo; Guiomar, RaquelBackground: The 2011/2012 season in Portugal, was characterized by an excess mortality and influenza vaccine failures. Predominant influenza A(H3) viruses with new antigenic properties were associated with potential host immune evasion. The aim of this study was to determine possible viral genetic causes that may be associated with cases of vaccine failure by performing a whole genome-based comparison of viruses detected in vaccinated (vacc) and unvaccinated (unvacc) individuals in 2011/2012 season. Methods: In 2011/12 season, 678 nasopharyngeal swabs from ILI cases were analyzed by the Portuguese NIC. Were detected 260 influenza A(H3) and 6 B/Yamagata viruses. For whole genome sequencing (WGS) 25 A(H3) positive samples, 20 from vacc and 5 from unvacc individuals, were selected. Each of the influenza genomic segments was submitted to standard or multiplex PCR amplification. WGS was performed on a MiSeq platform. Multiple alignments, phylogenetic and mutational analysis were performed using MEGA software 6.0. Results: Influenza A(H3) viruses clustered into different genetic clades, reflecting the clades circulating in Portugal, in2011/2012. 20 viruses belonged to clade 6 (reference strain A/Iowa/19/2010) and 5 viruses have clustered in the clade 3: 1 from clade 3A (A/Stockholm/18/2011), a second from clade 3B (A/England/259/2011) and 3 viruses from clade 3C (A/Victoria/361/2011). Viral genomes were highly similar at nucleotide level, ranging 98.2% – 100.0% of similarity. Matrix and nucleoprotein genomic segments were the most conserved, whereas the highest number of substitutions leading to amino acid changes was observed in hemagglutinin and neuraminidase segments (comparisons performed against the vaccine strain A/Perth/16/2009). The deduced amino acid sequences of viral proteins did not reveal any particular feature assigned to the group of vacc or unvacc individuals. Conclusions: In all 8 genomic segments of studied viruses no particular amino acid substitution was found to be associated with the vacc or unvacc cases. The observed differences were associated with the genetic distances between the clades to which viruses belong rather than with vaccine failure. Still, WGS in influenza surveillance is a powerful tool for monitoring the overall evolution of viral genome and establishment of molecular markers for, disease severity and drug resistance. This study points that a full evaluation of influenza vaccine failures should integrate not only data on virus characteristics, but also on host genetic polymorphisms related to immunity and serosurveys in order to better evaluate interindividual variation in influenza vaccine-induced immune responses.