scholarly journals Estimation of influenza activity in Vojvodina (Serbia) for five consecutive influenza seasons

2018 ◽  
Vol 75 (6) ◽  
pp. 589-597
Author(s):  
Mioljub Ristic ◽  
Mirjana Strbac ◽  
Snezana Medic ◽  
Vladimir Petrovic
Keyword(s):  
Influenza A ◽  
Influenza Season ◽  
Influenza Infection ◽  
Laboratory Data ◽  
Respiratory Illness ◽  
Case Definition ◽  
Influenza Surveillance ◽  
Influenza B ◽  
Case Definitions ◽  
Influenza A H1n1

Background/Aim. After pandemic 2009/10 influenza season, influenza A (H1N1)pdm09, A(H3N2) and B viruses have continued to circulate in the population. The aim of this study was to describe the epidemiological and virological characteristics of influenza and evaluate values of proposed case definitions of influenza like illness (ILI), severe acute respiratory illness (SARI) and acute respiratory distress syndrome (ARDS) for detecting laboratory-confirmed influenza cases in Vojvodina. Methods. We conducted a descriptive epidemiological study using surveillance reports and laboratory data from October 2010 to May 2015 (five surveillance seasons). Results. Out of 1,466 samples collected, 720 (49.1%) were laboratory confirmed as influenza. Influenza A infection was more frequently detected than influenza B infection. Using the case definition of ILI was a good predictor for influenza confirmation (p < 0.05) during 5 influenza seasons. The predominant age-range of patients with confirmed influenza A (42.2%) and B (43.0%) infections was 30 to 64, but the patients aged from 15 to 29 years were more likely to have influenza A (p = 0.0168). In the period from December to January, influenza A (17.8%) was more frequently registered than influenza B (7.6%). The highest number of deaths (19/38) and hospitalized patients (128/402) was registered during the last influenza season (2014/15). The immunosuppressed patients with confirmed influenza infection were more likely to have influenza B than influenza A (p = 0.0110). Conclusion. Our results indicate that influenza surveillance should be continued and expanded in order to fully assess the burden of the disease in given population.

scholarly journals Surveillance of influenza in the post-pandemic period in the Vojvodina, Serbia, October 2010 - May 2015

2017 ◽  
Vol 145 (7-8) ◽  
pp. 387-393
Author(s):  
Mioljub Ristic ◽  
Vesna Stojanovic ◽  
Vesna Milosevic ◽  
Jelena Radovanov ◽  
Tihomir Dugandzija ◽  
...  
Keyword(s):  
Influenza A ◽  
Laboratory Data ◽  
Weather Conditions ◽  
Respiratory Illness ◽  
Laboratory Method ◽  
World Health ◽  
School Age Children ◽  
Influenza Surveillance ◽  
Influenza B ◽  
Influenza A H1n1

Introduction/Objective. In August 2010, World Health Organization declared the beginning of the postpandemic phase of influenza surveillance. The aim of this study was to evaluate the epidemiological and virological characteristics of influenza and correlation between the influenza occurrence and weather conditions. Methods. We used surveillance reports of influenza and laboratory data from October 2010 to May 2015. Data for the analysis were collected through sentinel surveillance of influenza-like illness (ILI), severe acute respiratory illness (SARI), acute respiratory distress syndrome, and by virological surveillance. The nasal and throat swabs from all influenza cases were performed by the PCR laboratory method. Results. During the observed period, the highest rates of ILI were registered during the 2010/11 and 2012/13 seasons, with influenza A (H1N1)pdm09 and influenza B being predominant, respectively. The highest weekly age-specific rates of ILI were registered in school-age children (ages 5?14). Out of 1,466 samples collected, 720 (49.1%) were laboratory confirmed as influenza, and influenza A virus was more frequently detected than influenza B. Among confirmed cases of influenza, participation of patients with SARI or ILI was nearly equal (46% vs. 44.1%). There was a weak correlation observed between the decrease in temperature and rainfall and the increase in influenza detection (? = -0.04214 vs. ? = -0.01545, respectively, p > 0.05). Conclusion. There is a need for continuous surveillance in order to predict seasonal trends and prepare for a timely response to influenza outbreak.

scholarly journals What will the next influenza season bring about: seasonal influenza or the new A(H1N1)v? An analysis of German influenza surveillance data

2009 ◽  
Vol 14 (32) ◽  
Author(s):  
H Uphoff ◽  
S Geis ◽  
A Grüber ◽  
A M Hauri
Keyword(s):  
Influenza A ◽  
Seasonal Influenza ◽  
Influenza Season ◽  
Influenza Viruses ◽  
Moderate Intensity ◽  
Influenza Surveillance ◽  
Influenza B ◽  
Low Intensity ◽  
Influenza A H1n1 ◽  
Using Data

For the next influenza season (winter 2009-10) the relative contributions to virus circulation and influenza-associated morbidity of the seasonal influenza viruses A(H3N2), A(H1N1) and B, and the new influenza A(H1N1)v are still unknown. We estimated the chances of seasonal influenza to circulate during the upcoming season using data of the German influenza sentinel scheme from 1992 to 2009. We calculated type and subtype-specific indices for past exposure and the corresponding morbidity indices for each season. For the upcoming season 2009-10 our model suggests that it is unlikely that influenza A(H3N2) will circulate with more than a low intensity, seasonal A(H1N1) with more than a low to moderate intensity, and influenza B with more than a low to median intensity. The probability of a competitive circulation of seasonal influenza A with the new A(H1N1)v is low, increasing the chance for the latter to dominate the next influenza season in Germany.

Clinical symptoms cannot predict influenza infection during the 2013 influenza season in Bavaria, Germany

2015 ◽  
Vol 144 (5) ◽  
pp. 1045-1051 ◽  
Author(s):  
H. CAMPE ◽  
S. HEINZINGER ◽  
C. HARTBERGER ◽  
A. SING
Keyword(s):  
Clinical Symptoms ◽  
Respiratory Infections ◽  
Influenza Season ◽  
Influenza Infection ◽  
Clinical Signs ◽  
Diagnostic Value ◽  
Case Definition ◽  
Influenza Surveillance ◽  
Case Definitions ◽  
Laboratory Confirmation

SUMMARYFor influenza surveillance and diagnosis typical clinical symptoms are traditionally used to discriminate influenza virus infections from infections by other pathogens. During the 2013 influenza season we performed a multiplex assay for 16 different viruses in 665 swabs from patients with acute respiratory infections (ARIs) to display the variety of different pathogens causing ARI and to test the diagnostic value of both the commonly used case definitions [ARI, and influenza like illness (ILI)] as well as the clinical judgement of physicians, respectively, to achieve a laboratory-confirmed influenza diagnosis. Fourteen different viruses were identified as causing ARI/ILI. Influenza diagnosis based on clinical signs overestimated the number of laboratory-confirmed influenza cases and misclassified cases. Furthermore, ILI case definition and physicians agreed in only 287/651 (44%) cases with laboratory confirmation. Influenza case management has to be supported by laboratory confirmation to allow evidence-based decisions. Epidemiological syndromic surveillance data should be supported by laboratory confirmation for reasonable interpretation.

scholarly journals DETECTION OF INFLUENZA VIRUSES AMONG HOSPITALIZED CASES SUFFERING FROM SEVERE ACUTE RESPIRATORY ILLNESS (SARI) IN SANA’A CITY, YEMEN

2019 ◽  
Author(s):  
Dina Abdulljabbar Abdullah Al-Ademi ◽  
Abdulilah Hussein Al-Harazi ◽  
Hassan A. Al-Shamahy ◽  
Bushra Mohammed Jaadan
Keyword(s):  
Mortality Rate ◽  
Influenza A ◽  
Respiratory Illness ◽  
Hospitalized Patients ◽  
Influenza Viruses ◽  
Influenza Surveillance ◽  
Influenza B ◽  
Acute Respiratory Illness ◽  
Influenza A H1n1 ◽  
Severe Acute Respiratory Illness

Influenza is a major cause of morbidity and mortality around the world. So national influenza surveillance have been important for understanding the epidemiology of influenza over time. The aims of this study were to determine the prevalence rate of influenza viruses among hospitalized patients with severe acute respiratory illness (SARI), identify circulating types and subtypes of influenza viruses among them, and determine the risk factors associated with SARI. A total of 320 hospitalized patients suffering from SARI at Al Joumhouri University hospital in Sana’a city were enrolled; and their age was ranged from < 1 year to ≥ 56 years. Both nasopharyngeal and oro-pharyngeal swabs were collected from each patient and tested by using rRT-PCR technique for the detection of influenza A, influenza B and subtypes of influenza A viruses (A/H1N1(2009) and A/H3N2). The crude prevalent rate of influenza viruses among SARI patients was 10.9%;the female rate was 12.4%, and the male rate was 9.9%. The rate of Flu A in the total SARI cases was 5.9% and for Flu B was 5%. In addition 3.8% of SARI patients were suffering from influenza A/H3N2, 2.2% from influenza A/H1N1(2009) infections; and the mortality rate for influenza infections was 17.1%. Also, a high mortality rate was occurred in influenza infections in age groups 36-45 years and 6-15 years. Also, there was a significant association between flu infection; and 46-55 years group (OR=2.8), Winter time (OR=17.5), cardiac diseases (OR=9.1), and diabetic mellitus (OR=3.7). In conclusion: both influenza A and B were represented as a causative agents of SARI, and Influenza A/H3N2 was present subtype followed by A/H1N1(2009). The frequency of influenza viruses ascertain among SARI patients in Yemen highlights the need for health authorities to develop strategies to reduce morbidity among at-risk population in the course of vaccine recommendation.

scholarly journals Virological analysis of fatal influenza cases in the United Kingdom during the early wave of influenza in winter 2010/11

2011 ◽  
Vol 16 (1) ◽  
Author(s):  
J Ellis ◽  
M Galiano ◽  
R Pebody ◽  
A Lackenby ◽  
CI Thompson ◽  
...  
Keyword(s):  
United Kingdom ◽  
Vaccine Strain ◽  
Influenza A ◽  
Influenza Season ◽  
Severe Illness ◽  
Influenza B ◽  
The United Kingdom ◽  
Influenza A H1n1 ◽  
Influenza Activity ◽  
Children And Young Adults

The 2010/11 winter influenza season is underway in the United Kingdom, with co-circulation of influenza A(H1N1)2009 (antigenically similar to the current 2010/11 vaccine strain), influenza B (mainly B/Victoria/2/87 lineage, similar to the 2010/11 vaccine strain) and a few sporadic influenza A(H3N2) viruses. Clinical influenza activity has been increasing. Severe illness, resulting in hospitalisation and deaths, has occurred in children and young adults and has predominantly been associated with influenza A(H1N1)2009, but also influenza B viruses.

scholarly journals Co-circulation of the two influenza B lineages during 13 consecutive influenza surveillance seasons in Italy, 2004–2017

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Simona Puzelli ◽  
◽  
Angela Di Martino ◽  
Marzia Facchini ◽  
Concetta Fabiani ◽  
...  
Keyword(s):  
Influenza A ◽  
Respiratory Illness ◽  
Influenza Surveillance ◽  
Influenza B Virus ◽  
Influenza B ◽  
Virus Infections ◽  
Ha Gene ◽  
B Virus ◽  
B Lineage ◽  
Trivalent Vaccine

Abstract Background Since 1985, two antigenically distinct lineages of influenza B viruses (Victoria-like and Yamagata-like) have circulated globally. Trivalent seasonal influenza vaccines contain two circulating influenza A strains but a single B strain and thus provide limited immunity against circulating B strains of the lineage not included in the vaccine. In this study, we describe the characteristics of influenza B viruses that caused respiratory illness in the population in Italy over 13 consecutive seasons of virological surveillance, and the match between the predominant influenza B lineage and the vaccine B lineage, in each season. Methods From 2004 to 2017, 26,886 laboratory-confirmed influenza cases were registered in Italy, of which 18.7% were type B. Among them, the lineage of 2465 strains (49%) was retrieved or characterized in this study by a real-time RT-PCR assay and/or sequencing of the hemagglutinin (HA) gene. Results Co-circulation of both B lineages was observed each season, although in different proportions every year. Overall, viruses of B/Victoria and B/Yamagata lineages caused 53.3 and 46.7% of influenza B infections, respectively. A higher proportion of infections with both lineages was detected in children, and there was a declining frequency of B/Victoria detections with age. A mismatch between the vaccine and the predominant influenza B lineage occurred in eight out of thirteen influenza seasons under study. Considering the seasons when B accounted for > 20% of all laboratory-confirmed influenza cases, a mismatch was observed in four out of six seasons. Phylogenetic analysis of the HA1 domain confirmed the co-circulation of both lineages and revealed a mixed circulation of distinct evolutionary viral variants, with different levels of match to the vaccine strains. Conclusions This study contributes to the understanding of the circulation of influenza B viruses in Italy. We found a continuous co-circulation of both B lineages in the period 2004–2017, and determined that children were particularly vulnerable to Victoria-lineage influenza B virus infections. An influenza B lineage mismatch with the trivalent vaccine occurred in about two-thirds of cases.

scholarly journals Estimating vaccine effectiveness against laboratory-confirmed influenza among children and adolescents in Lower Saxony and Saxony-Anhalt, 2012–2016

2017 ◽  
Vol 146 (1) ◽  
pp. 78-88 ◽  
Author(s):  
A. MÖHL ◽  
L. GRÄFE ◽  
C. HELMEKE ◽  
D. ZIEHM ◽  
M. MONAZAHIAN ◽  
...  
Keyword(s):  
Influenza A ◽  
Respiratory Illness ◽  
Vaccine Effectiveness ◽  
Federal State ◽  
Influenza B ◽  
Surveillance Systems ◽  
Lower Saxony ◽  
Federal States ◽  
German Federal States ◽  
Influenza A H1n1

SUMMARYInfluenza vaccine effectiveness (VE) has to be estimated anew for every season to explore vaccines’ protective effect in the population. We report VE estimates against laboratory-confirmed influenza A(H1N1)pdm09, A(H3N2) and influenza B among children aged 2–17 years, using test-negative design. Pooled data from two German federal states’ surveillance systems for acute respiratory illness from week 40/2012 to 20/2016 was used, yielding a total of 10 627 specimens. Odds ratios and 95% confidence intervals (95% CIs) for the association between laboratory-confirmed influenza and vaccination status were calculated by multivariate logistic regression adjusting for age, sex, illness onset and federal state. VE was estimated as 1-Odds Ratio. Overall adjusted VE was 33% (95% CI: 24·3–40·7). A strong variation of VE between the seasons and subtypes was observed: highest season- and subtype-specific VE of 86·2% (95% CI: 41·3–96·7) was found against A(H1N1)pdm09 in 7–17-year-olds in 2015/16. Low estimates of VE were observed against A(H3N2) in any season, e.g. 1·5% (95% CI: −39·3–30·3) in 2014/15. Estimates showed a tendency to higher VE among 7–17-year-old children, but differences were not statistically significant. Although our findings are common in studies estimating influenza VE, we discussed several explanations for observed low VE.

Dual and Triple Infections With Influenza A and B Viruses: A Case-Control Study in Southern Brazil

2019 ◽  
Vol 220 (6) ◽  
pp. 961-968 ◽  
Author(s):  
Tatiana Schäffer Gregianini ◽  
Ivana R Santos Varella ◽  
Patricia Fisch ◽  
Letícia Garay Martins ◽  
Ana B G Veiga
Keyword(s):  
Influenza Virus ◽  
Influenza A ◽  
Clinical Symptoms ◽  
Antiviral Treatment ◽  
Influenza Virus Infection ◽  
H3n2 Virus ◽  
Influenza Surveillance ◽  
Influenza B Virus ◽  
Influenza B ◽  
Influenza A H1n1

Abstract Influenza surveillance is important for disease control and should consider possible coinfection with different viruses, which can be associated with disease severity. This study analyzed 34 459 patients with respiratory infection from 2009 to 2018, of whom 8011 were positive for influenza A virus (IAV) or influenza B virus (IBV). We found 18 cases of dual influenza virus infection, including coinfection with 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09) and influenza A(H3N2) virus (1 case), A(H1N1)pdm09 and IBV (6 cases), A(H3N2) and IBV (8 cases), and nonsubtyped IAV and IBV (3 cases); and 1 case of triple infection with A(H3N2), A(H1N1)pdm09, and IBV. Compared with 76 monoinfected patients, coinfection was significantly associated with cardiopathy and death. Besides demographic characteristics and clinical symptoms, we assessed vaccination status, antiviral treatment, timeliness of antiviral use, hospitalization, and intensive care unit admission, but no significant differences were found between coinfected and monoinfected cases. Our findings indicate that influenza virus coinfection occurs more often than previously reported and that it can lead to a worse disease outcome.

scholarly journals Occurrence of influenza B/Hong Kong-Like strains in Brazil, during 2002

2003 ◽  
Vol 45 (1) ◽  
pp. 51-52 ◽  
Author(s):  
Terezinha Maria de Paiva ◽  
Maria Akiko Ishida ◽  
Maria Gisele Gonçalves ◽  
Margareth Aparecida Benega ◽  
Maria Candida Oliveira de Souza ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Hong Kong ◽  
Influenza A ◽  
Vaccination Campaign ◽  
Age Groups ◽  
Respiratory Illness ◽  
The Elderly ◽  
Influenza B ◽  
Surveillance Period ◽  
Influenza A H1n1

Through the influenza virus surveillance from January to October 2002, influenza B/Hong Kong-like strains circulating in the Southeast and Centre East regions of Brazil have been demonstrated. This strain is a variant from B/Victoria/02/88 whose since 1991 and until recently have been isolated relatively infrequently and have been limited to South-Eastern Asia. A total of 510 respiratory secretions were collected from patients 0 to 60 years of age, with acute respiratory illness, living in the Southeast and Centre East regions of Brazil, of which 86 (17.13%) were positive for influenza virus. Among them 12 (13.95%) were characterized as B/Hong Kong/330/2001; 3 (3.49%) as B/Hong Kong/1351/2002 a variant from B/Hong Kong/330/2001; 1 (1.16%) as B/Sichuan/379/99; 1 (1.16%) as B/Shizuoka/5/2001, until now. The percentages of cases notified during the surveillance period were 34.88%, 15.12%, 15.12%, 4.65%, 15.12%, 13.95%, in the age groups of 0-4, 5-10, 11-15, 16-20, 21-30, 31-50, respectively. The highest proportion of isolates was observed among children younger than 4 years but serious morbidity and mortality has not been observed among people older than 65 years, although B influenza virus component for vaccination campaign 2002 was B/Sichuan/379/99 strain. This was probably due to the elderly protection acquired against B/Victoria/02/88. In addition, in influenza A/Panama/2007/99-like (H3N2) strains 22 (25.58%) were also detected, but influenza A(H1N1) has not been detected yet.

Influenza Project in Myanmar

2014 ◽  
Vol 9 (5) ◽  
pp. 842-847
Author(s):  
Reiko Saito ◽  
◽  
Yadanar Kyaw ◽  
Yi Yi Myint ◽  
Clyde Dapat ◽  
...  
Keyword(s):  
Influenza A ◽  
Drug Susceptibility ◽  
Influenza Viruses ◽  
World Health ◽  
Influenza Surveillance ◽  
Influenza B ◽  
Laboratory Capacity ◽  
Influenza A H1n1 ◽  
Resistant Strains ◽  
Health Organization

The epidemiological study of influenza in Southeast Asia is limited. We surveyed influenza in Myanmar from 2007 to 2013. Nasopharyngeal swabs were collected from patients in the two cities of Yangon and Nay Pyi Taw. Samples were screened using rapid influenza diagnostic kits and identified by virus isolation. Isolates were characterized by cyclingprobe-based real-time PCR, drug susceptibility assay, and sequencing. Samples collected numbered 5,173, from which 1,686 influenza viruses were isolated during the seven-year study period. Of these, 187 strains were of seasonal influenza A(H1N1), 274 of influenza A(H1N1)pdm09, 791 of influenza A(H3N2), and 434 of influenza B. Interestingly, two zanamivir and amantadine-resistant strains each were detected in 2007 and 2008. These rare dual-resistant strains had a Q136K mutation in the NA protein and S31N substitution in the M2 protein. Our collaboration raised the influenza surveillance laboratory capacity in Myanmar and led Yangon’s National Health Laboratory – one of the nation’s leading research institutes – to being designated a National Influenza Center by the World Health Organization.

Sign in / Sign up

Export Citation Format

Share Document