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

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Morbidity patterns associated with seasonal influenza A/H1N1in Swaziland

Online Journal of Public Health Informatics ◽

10.5210/ojphi.v10i1.8939 ◽

2018 ◽

Vol 10 (1) ◽

Author(s):

Vusie Lokotfwako ◽

Nhlanhla Nhlabatsi ◽

Phinda Khumalo ◽

Siphiwe Shongwe ◽

Bongani Tsabedze ◽

...

Keyword(s):

Influenza Virus ◽

Influenza A ◽

Seasonal Influenza ◽

Index Case ◽

Influenza Viruses ◽

Influenza Surveillance ◽

Influenza B ◽

Epidemic Disease ◽

Influenza A H1n1 ◽

Private Laboratory

ObjectiveTo establish morbidity patterns of influenza A/H1N1 in Swaziland from 10th July to 15th August 2017.IntroductionInfluenza infection is caused by the influenza virus, a single-stranded RNA virus belonging to the Orthomyxoviridae family. Influenza viruses are classified as types A, B and C. Influenza A and B viruses can cause epidemic disease in humans and type C viruses usually cause a mild, cold-like illness. The influenza virus spreads rapidly around the world in seasonal epidemics, resulting in significant morbidity and mortality. On the 10th of July 2017, a case of confirmed Influenza A/H1N1 was reported through the immediate disease notification system from a private hospital in the Hhohho region. A 49 year old female was diagnosed of Influenza A/H1N1 after presenting with flu-like symptoms. Contacts of the index case were followed and further positive cases were identified.MethodsUpon identification of the index case, the rapid response teams conducted further investigations. Two nasal swaps from each sample were taken and sent to a private laboratory in South Africa for the detection of the virus RNA using RT-PCR to assess for the presence Influenza A, B and Influenza A/H1N1. Further laboratory results were sourced from a private laboratory to monitor trends of influenza. Data was captured and analyzed in STATA version 12 from STATA cooperation. Descriptive statistics were carried out using means and standard deviations. The Pearson Chi square test and student t test were used to test for any possible association between influenza A/H1N1 and the explanatory variables (age and sex).ResultsSurveillance data captured between 10th July 2017 and 15th August 2017 indicated that a total of 87 patients had their samples taken for laboratory confirmation. There were 45 females and 42 males and the mean age was 27 years (SD= 17). At least 25 of the 87 patients tested positive for influenza A while only 1 tested positive for influenza B. The prevalence of influenza A/H1N1 was 16%. The prevalence of influenza A/H1N1 among males was 19% compared to 13% in females; however the difference was not statistically significant (p=0.469). There was no association noted between age and influenza A/H1N1 (p=427). Upon further sub-typing results indicated that the circulating strain was influenza A/H1N1 pdm 09 strain which is a seasonal influenza. The epidemic task forces held weekly and ad-hoc meetings to provide feedback to principals and health messaging to the general population to allay anxiety.ConclusionsThough WHO has classified the influenza A/H1N1 strain pdm 0029 as a seasonal influenza, surveillance remains important for early detection and management. There is therefore an urgent need to set up sentinel sites to monitor and understand the circulating influenza strains. Health promotion remains crucial to dispel anxiety as the general public still link any influenza to the 2009 pandemic influenza. Finally the Ministry of Health should consider introducing influenza vaccines into the routine immunization schedule especially for children.References1. Global Epidemiological Surveillance Standards for Influenza. 2014 [cited 2015 15 April]; Available from: http://www.who.int/influenza/resources/documents/influenza_surveillance_manual/en/.2. Human cases of influenza at the human-animal interface, 2013. Wkly Epidemiol Rec, 2014.89(28): p. 309-20.3. WHO Global Influenza Surveillance Network. Manual for the laboratory diagnosis and virological surveillance of influenza. 2011 [cited 2015 April27]; Available from: http://www.who.int/influenza/gisrs_laboratory/manual_diagnosis_surveillance_influenza/en/.

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Report on influenza viruses received and tested by the Melbourne WHO Collaborating Centre for Reference and Research on Influenza in 2019

Communicable Diseases Intelligence ◽

10.33321/cdi.2021.45.43 ◽

2021 ◽

Vol 45 ◽

Author(s):

Heidi Peck ◽

Jean Moselen ◽

Sook Kwan Brown ◽

Megan Triantafilou ◽

Hilda Lau ◽

...

Keyword(s):

Influenza A ◽

Seasonal Influenza ◽

Significant Proportion ◽

Influenza Viruses ◽

World Health ◽

Influenza Surveillance ◽

Influenza B ◽

Surveillance And Response ◽

Influenza A H1n1 ◽

Potential Use

As part of its role in the World Health Organization’s (WHO) Global Influenza Surveillance and Response System (GISRS), the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne received a record total of 9,266 human influenza positive samples during 2019. Viruses were analysed for their antigenic, genetic and antiviral susceptibility properties. Selected viruses were propagated in qualified cells or embryonated hen’s eggs for potential use in seasonal influenza virus vaccines. In 2019, influenza A(H3N2) viruses predominated over influenza A(H1N1)pdm09 and B viruses, accounting for a total of 51% of all viruses analysed. The majority of A(H1N1)pdm09, A(H3N2) and influenza B viruses analysed at the Centre were found to be antigenically similar to the respective WHO recommended vaccine strains for the Southern Hemisphere in 2019. However, phylogenetic analysis indicated that a significant proportion of circulating A(H3N2) viruses had undergone genetic drift relative to the WHO recommended vaccine strain for 2019. Of 5,301 samples tested for susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir, four A(H1N1)pdm09 viruses showed highly reduced inhibition with oseltamivir, one A(H1N1)pdm09 virus showed highly reduced inhibition with zanamivir and three B/Victoria viruses showed highly reduced inhibition with zanamivir.

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National influenza mid-season report, 2020–2021

Canada Communicable Disease Report ◽

10.14745/ccdr.v47i01a01 ◽

2021 ◽

Vol 47 (1) ◽

pp. 1-4

Author(s):

Lisa Lee ◽

Kelly Butt ◽

Steven Buckrell ◽

Andrea Nwosu ◽

Claire Sevenhuysen ◽

...

Keyword(s):

Influenza A ◽

Seasonal Influenza ◽

Influenza Season ◽

Influenza Viruses ◽

Resistance Testing ◽

Influenza Surveillance ◽

Influenza B ◽

Strain Characterization ◽

Influenza Activity ◽

Low Levels

Canada's national influenza season typically starts in the latter half of November (week 47) and is defined as the week when at least 5% of influenza tests are positive and a minimum of 15 positive tests are observed. As of December 12, 2020 (week 50), the 2020-2021 influenza season had not begun. Only 47 laboratory-confirmed influenza detections were reported from August 23 to December 12, 2020; an unprecedentedly low number, despite higher than usual levels of influenza testing. Of this small number of detections, 64% were influenza A and 36% were influenza B. Influenza activity in Canada was at historically low levels compared with the previous five seasons. Provinces and territories reported no influenza-associated adult hospitalizations. Fewer than five hospitalizations were reported by the paediatric sentinel hospitalization network. With little influenza circulating, the National Microbiology Laboratory had not yet received samples of influenza viruses collected during the 2020-2021 season for strain characterization or antiviral resistance testing. The assessment of influenza vaccine effectiveness, typically available in mid-March, is expected to be similarly limited if low seasonal influenza circulation persists. Nevertheless, Canada's influenza surveillance system remains robust and has pivoted its syndromic, virologic and severe outcomes system components to support coronavirus disease 2019 (COVID-19) surveillance. Despite the COVID-19 pandemic, the threat of influenza epidemics and pandemics persists. It is imperative 1) to maintain surveillance of influenza, 2) to remain alert to unusual or unexpected events and 3) to be prepared to mitigate influenza epidemics when they resurge.

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Epidemiology of influenza: findings from surveillance system of 40 hospital in Thailand, 2010-2019

European Journal of Public Health ◽

10.1093/eurpub/ckaa165.1098 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

T Eamchotchawalit ◽

P Piyaraj ◽

P Narongdej ◽

S Charoensakulchai ◽

C Chanthowong

Keyword(s):

Real Time ◽

Surveillance System ◽

Influenza A ◽

Seasonal Influenza ◽

Influenza Viruses ◽

Cold Chain ◽

Influenza Surveillance ◽

Influenza B ◽

Private Hospitals ◽

Influenza A H1n1

Abstract Background Although recent efforts from some Asian countries to describe burden of influenza disease and seasonality, these data are missing for the vast majority, including the private section of Thailand. A near real-time laboratory-based influenza surveillance system, in a network of 40 hospitals was implemented aiming to determine influenza strains circulating in the private hospitals of Thailand and know characteristics, trend and burden of influenza viruses. Methods We obtained the data by monitoring patients with influenza-like illness (ILI) at a network of 40 private hospitals across Thailand. Throat-swab specimens in viral transport media were collected and transported within 24 h of collection using a cold-chain system. The respiratory samples were tested by rapid influenza diagnostic tests and real-time reverse transcription polymerase chain reaction. Results From January 2010 to November 2019, a total of 1,300,594 subjects were tested and 320,499 cases of influenza were identified. Of those positive cases, 116,317(36.3%) were influenza type B, 185,512(57.9%) were influenza A unspecified subtype, 8,833(2.7%) were influenza A(H1N1)pdm2009 and 6,371(1.9%) were seasonal influenza A(H3N2). Positive rate were 50.5 and 49.5 in female and male. Positivity rate was 41.4% in persons 15-49 years followed by 29.1% in 15-14 years, 17.6% in under five children and 11.7% in > 49 years. In 2018-2019 season, the highest positivity rate observed in February and March (39.3%) followed by April (34.2%) and January (32.3%) while the lowest positivity rate was in May (18.1%). Conclusions In Thailand, seasonal Influenza A(H3N2), Influenza A(H1N1)pdm2009 and Influenza B viruses were circulating during 2010-2019. In last season, positivity rate and number of cases peaked in February and March. Key messages Influenza is one of public health problems in Thailand. The need to introduce influenza vaccine and antivirus is important to prevent and treat the disease in future.

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Influenza Project in Myanmar

Journal of Disaster Research ◽

10.20965/jdr.2014.p0842 ◽

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.

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Report on influenza viruses received and tested by the Melbourne WHO Collaborating Centre for Reference and Research on Influenza in 2017

Communicable Diseases Intelligence ◽

10.33321/cdi.2019.43.25 ◽

2019 ◽

Vol 43 ◽

Cited By ~ 1

Author(s):

Merryn Roe ◽

Matthew Kaye ◽

Pina Iannello ◽

Hilda Lau ◽

Iwona Buettner ◽

...

Keyword(s):

Influenza A ◽

Seasonal Influenza ◽

Vaccine Virus ◽

Influenza Viruses ◽

World Health ◽

Influenza Surveillance ◽

Influenza B ◽

Neuraminidase Inhibitors ◽

Response System ◽

Surveillance And Response

As part of its role in the World Health Organization’s (WHO) Global Influenza Surveillance and Response System (GISRS), the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne received a record total of 5866 human influenza positive samples during 2017. Viruses were analysed for their antigenic, genetic and antiviral susceptibility properties and were propagated in qualified cells and hens’ eggs for use as potential seasonal influenza vaccine virus candidates. In 2017, influenza A(H3) viruses predominated over influenza A(H1)pdm09 and B viruses, accounting for a total of 54% of all viruses analysed. The majority of A(H1)pdm09, A(H3) and influenza B viruses analysed at the Centre were found to be antigenically similar to the respective WHO recommended vaccine strains for the Southern Hemisphere in 2017. However, phylogenetic analysis indicated that the majority of circulating A(H3) viruses had undergone genetic drift relative to the WHO recommended vaccine strain for 2017. Of 3733 samples tested for susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir, only two A(H1)pdm09 viruses and one A(H3) virus showed highly reduced inhibition by oseltamivir, while just one A(H1)pdm09 virus showed highly reduced inhibition by zanamivir.

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Circulating influenza viruses and the effectiveness of seasonal influenza vaccine in Romania, season 2012-2013 / Virusurile gripale circulante și eficacitatea vaccinului gripal sezonier în România, în sezonul 2012-2013

Revista Romana de Medicina de Laborator ◽

10.1515/rrlm-2015-0007 ◽

2015 ◽

Vol 23 (1) ◽

Author(s):

Daniela Pitigoi ◽

George Necula ◽

Viorel Alexandrescu ◽

Maria Elena Mihai ◽

Carmen Maria Cherciu ◽

...

Keyword(s):

Influenza Vaccine ◽

Vaccine Strain ◽

Influenza A ◽

Seasonal Influenza ◽

Influenza Viruses ◽

Nucleotide Sequencing ◽

Influenza B ◽

Seasonal Influenza Vaccine ◽

Negative Case ◽

Influenza A H1n1

AbstractBackgound. Using influenza epidemiological and virological surveillance data, we aimed at investigating the profile of influenza viruses circulating in Romania during the season 2012-2013 and estimating the effectiveness (VE) of the seasonal vaccine. Methods. We tested all specimens collected from patients with influenza like illness (ILI) in the national surveillance system between week 40/2012 to week 20/2013. Influenza A/B positive specimens identified by molecular detection (RT-PCR) were further characterized. We used hemagglutination inhibition assay for antigenic characterization and chemiluminiscence assay for the antiviral susceptibility testing. Subsequently we conducted nucleotide sequencing of hemagglutinin and neuraminidase genes and phylogenetic tree analyses. We estimated influenza VE using the test negative case-control study design, as 1-odds ratio of vaccination among ILI cases positive for influenza and ILI negative controls. Results and Discussions. We tested 1087 specimens, and 537 cases were positive (56.2% influenza B, 40.6% A(H1N1)pdm09, 3.2% A(H3N2). Sixty-four influenza viruses were antigenically and/or genetically characterized. A(H1N1)pdm09 viruses were related to the vaccine strain A/ California/07/2009 and clustered with genetic group 6 similar to A/St. Petersburg/27/2011. Influenza B viruses belonged to clade 2 of type B/Yamagata lineage, related to B/Estonia/55669/2011 except one, B/Victoria lineage, representative strain B/Brisbane/60/2008. A(H3) viruses clustered with group 3C of the A/Victoria/208/2009 clade, similar to the vaccine strain A/Victoria/361/2011. All tested strains (57) demonstrated susceptibility to oseltamivir and zanamivir. The adjusted seasonal influenza vaccine effectiveness against influenza A(H1N1)pdm09 (N=119) was 76.9% (95% CI: -113.4, 98.5), suggesting a good protection, consistent with the good match between the vaccine and circulating strains.

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Influenza-associated mortality for circulatory and respiratory causes during the 2013-2014 through the 2018-2019 influenza seasons in Russia

10.1101/19012856 ◽

2019 ◽

Author(s):

Edward Goldstein

Keyword(s):

Influenza Vaccination ◽

Influenza A ◽

Temporal Trends ◽

Influenza Viruses ◽

Federal State ◽

Influenza B ◽

Influenza A H1n1 ◽

Using Data ◽

Antiviral Medications ◽

Respiratory Causes

AbstractBackgroundInformation on influenza-associated mortality in Russia is limited and largely related to deaths with influenza in the diagnosis that represent a small fraction of all influenza-associated deaths.MethodsUsing previously developed methodology (Goldstein et al., Epidemiology 2012), we regressed the monthly rates of mortality for respiratory causes, as well as circulatory causes (available from the Russian Federal State Statistics Service (Rosstat)) during the 2013/14 through the 2018/19 influenza seasons linearly against the monthly proxies for the incidence of influenza A/H3N2, A/H1N1 and B (obtained using data from the Smorodintsev Research Institute of Influenza (RII) on influenza/ARI consultations, testing of respiratory specimens and genetic/antigenic characterization of influenza viruses), adjusting for the baseline rates of mortality not associated with influenza circulation and temporal trends.ResultsFor the 2013/14 through the 2018/19 seasons, influenza circulation was associated with an average annual 17636 (95% CI (9482,25790)) deaths for circulatory causes and 4179 (3250,5109) deaths for respiratory causes, with the largest number of deaths (32298 (18071,46525) for circulatory causes and 6689 (5019,8359) for respiratory causes) estimated during the 2014/15 influenza season. Influenza A/H3N2 was responsible for 51.8% of all circulatory influenza-associated deaths and 37.2% of all respiratory influenza-associated deaths. Influenza A/H1N1 was responsible for 23.4% of all circulatory influenza-associated deaths and 29.5% of all respiratory influenza-associated deaths. Influenza B was responsible for 24.9% of all circulatory influenza-associated deaths and 33.3% of all respiratory influenza-associated deaths, with the overwhelming majority of those deaths being caused by the B/Yamagata viruses. Compared to the 2013/14 through the 2015/16 seasons, during the 2016/17 through the 2018/19 seasons (when levels of influenza vaccination were significantly higher), the volume of influenza-associated mortality declined by about 16.1%, or 3809 annual respiratory and circulatory deaths.ConclusionsInfluenza circulation is associated with a substantial mortality burden in Russia, particularly for circulatory deaths, with some reduction in mortality rates observed following the major increase in influenza vaccination coverage. Those results support the potential utility of further extending the levels of influenza vaccination, the use of quadrivalent influenza vaccines, and extra efforts for protecting individuals with circulatory disease in Russia, including vaccination and the use of antiviral medications.

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Report on influenza viruses received and tested by the Melbourne WHO Collaborating Centre for Reference and Research on Influenza in 2018

Communicable Diseases Intelligence ◽

10.33321/cdi.2020.44.16 ◽

2020 ◽

Vol 44 ◽

Author(s):

Olivia H Price ◽

Natalie Spirason ◽

Cleve Rynehart ◽

Sook Kwan Brown ◽

Angela Todd ◽

...

Keyword(s):

Influenza A ◽

Seasonal Influenza ◽

Significant Proportion ◽

Vaccine Virus ◽

Influenza Viruses ◽

World Health ◽

Influenza Surveillance ◽

Influenza B ◽

Response System ◽

Surveillance And Response

As part of its role in the World Health Organization’s (WHO) Global Influenza Surveillance and Response System (GISRS), the WHO Collaborating Centre for Reference and Research on Influenza in Melbourne received a total of 3993 human influenza-positive samples during 2018. Viruses were analysed for their antigenic, genetic and antiviral susceptibility properties. Selected viruses were propagated in qualified cells or hens’ eggs for use as potential seasonal influenza vaccine virus candidates. In 2018, influenza A(H1)pdm09 viruses predominated over influenza A(H3) and B viruses, accounting for a total of 53% of all viruses analysed. The majority of A(H1)pdm09, A(H3) and influenza B viruses analysed at the Centre were found to be antigenically similar to the respective WHO-recommended vaccine strains for the Southern Hemisphere in 2018. However, phylogenetic analysis indicated that a significant proportion of circulating A(H3) viruses had undergone genetic drift relative to the WHO-recommended vaccine strain for 2018. Of 2864 samples tested for susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir, three A(H1)pdm09 viruses showed highly reduced inhibition by oseltamivir, while one B/Victoria virus showed highly reduced inhibition by both oseltamivir and zanamivir.

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A multiplex one-step real-time RT-PCR assay for influenza surveillance

Eurosurveillance ◽

10.2807/ese.16.07.19798-en ◽

2011 ◽

Vol 16 (7) ◽

Author(s):

I Huber ◽

H Campe ◽

D Sebah ◽

C Hartberger ◽

R Konrad ◽

...

Keyword(s):

Real Time ◽

High Throughput ◽

Influenza A ◽

Multiplex Assay ◽

Influenza Viruses ◽

Influenza Surveillance ◽

Influenza B ◽

Rt Pcr ◽

Influenza A H1n1 ◽

One Step

For surveillance purposes real-time PCR assays for influenza viruses had to be adapted to the pandemic influenza A(H1N1)2009 strain. We combined published primers and probes for influenza A, influenza B and an internal amplification control with a detection system for influenza A(H1N1)2009 to set up a rapid, reliable, simple and cost-effective high-throughput multiplex one-step real-time RT-PCR. The workflow also includes automated sample preparation for high-throughput screening. The lower limit of detection of the multiplex assay was 3.5x102 RNA copies per PCR reaction. The diagnostic sensitivity of the multiplex assay was 87.7%, but increased to 99.4% for influenza-positive samples yielding Ct values of less than 34 cycles in the respective diagnostic assay. High specificity was confirmed by sequencing and correct detection of 15 reference samples from two quality assurance studies. The multiplex PCR was introduced for surveillance of samples from a network of general practitioners and paediatricians in Bavaria, Germany during the influenza pandemic of 2009. Comparison with surveillance data from reported cases proved the reliability of the multiplex assay for influenza surveillance programmes.

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