scholarly journals Surveillance of influenza viruses isolated from travellers at Nagoya International Airport

2000 ◽  
Vol 124 (3) ◽  
pp. 507-514 ◽  
Author(s):  
K. SATO ◽  
T. MORISHITA ◽  
E. NOBUSAWA ◽  
Y. SUZUKI ◽  
Y. MIYAZAKI ◽  
...  

In order to conduct a survey of influenza viruses entering Japan via travellers arriving by airplanes, gargle solutions were collected from passengers who reported to the quarantine station of Nagoya International Airport complaining of respiratory symptoms. From 504 samples collected between August 1996 and March 1999, 30 influenza virus strains were isolated. Twenty-eight of the isolates were influenza A (H3N2) viruses and two were influenza B viruses. No H1N1 virus was isolated. Among 28 isolates of H3N2 virus, 3 strains were obtained outside the influenza season. Nucleotide sequences of the haemagglutinin (HA) genes of these isolates along with those from domestic patients were analysed in order to determine the influence of imported influenza viruses by travellers on epidemics in Japan. From the phylogenetic and chronological aspects, the possibility was suggested in one case in 1997/8 and two in the 1998/9 season that imported virus by travellers may have influenced the domestic influenza epidemics.

1995 ◽  
Vol 114 (3) ◽  
pp. 511-520 ◽  
Author(s):  
I. H. Brown ◽  
P. A. Harris ◽  
D. J. Alexander

SUMMARYSamples from a sow serum bank representative of the pig population of Great Britain collected during 1991–2, were examined for antibodies to influenza A, B and C viruses, using viruses which had been isolated from a variety of hosts. For influenza A viruses there was evidence of the continued circulation of ‘classical swine’ H1N1 virus (26%) seroprevalence), and human H3N2 viruses (39%) which are antigenically most closely-related to A/Port Chalmers/1/73 virus. In addition antibodies were detected to A/swine/England/201635/92 (8%), a strain of H3N2 virus which appears to have arisen by antigenic drift from conventional H3N2 swine strains. Specific antibodies (2%) were detected to an H1N1 virus (A/swine/England/195852/92) related most closely to avian H1N1 strains. In tests with human H1N1 and H3N2 viruses, excluding isolates from pigs, the highest seroprevalence was detected to the prevailing strains from the human population. Serological tests with avian H4 and H10, human H2, equine 1 and 2 influenza A viruses were all negative. Seven pigs seropositive by haemagglutination-inhibition, virus neutralization and immunoblotting assays for antibody to influenza B virus, were randomly distributed geographically suggesting that influenza B viruses may be transmitted to pigs but fail to spread. The seroprevalence to influenza C viruses was 9·9% indicating that these viruses are widespread in pigs. These results provide further evidence that the pig can be infected by a number of influenza viruses, some of which may have significance in the epidemiology of human influenza.


2014 ◽  
Vol 2014 ◽  
pp. 1-3
Author(s):  
Adriano Peris ◽  
Giovanni Zagli ◽  
Pasquale Bernardo ◽  
Massimo Bonacchi ◽  
Morena Cozzolino ◽  
...  

Pandemic influenza virus A(H1N1) 2009 was associated with a higher risk of viral pneumonia in comparison with seasonal influenza viruses. The influenza season 2011-2012 was characterized by the prevalent circulation of influenza A(H3N2) viruses. Whereas most H3N2 patients experienced mild, self-limited influenza-like illness, some patients were at increased risk for influenza complications because of age or underlying medical conditions. Cases presented were patients admitted to the Intensive Care Unit (ICU) of ECMO referral center (Careggi Teaching Hospital, Florence, Italy). Despite extracorporeal membrane oxygenation treatment (ECMO), one patient with H3N2-induced ARDS did not survive. Our experience suggests that viral aetiology is becoming more important and hospitals should be able to perform a fast differential diagnosis between bacterial and viral aetiology.


2009 ◽  
Vol 14 (32) ◽  
Author(s):  
H Uphoff ◽  
S Geis ◽  
A Grüber ◽  
A M Hauri

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.


2020 ◽  
pp. 26-28
Author(s):  
I. A. Malchikov ◽  
A. V. Slobodenyuk ◽  
I. V. Vyalykh ◽  
A. Yu. Markaran ◽  
Yu. V. Grigorieva ◽  
...  

Donor blood serum was tested to detect antibodies against circulating influenza viruses. The titer of specific antibodies was determined in the hemagglutination inhibition test (RTGA) against influenza viruses A/California/07/09(H1N1) pdm09, A/HongKong/4801/14(H3N2) and B/Brisben/46/15. In the pre-epidemic period 2018–2019, the immune layer of people with conditionally protective titers of antiviral antibodies was detected in terms of the lowest to A(H3N2) virus (50.0 %), the highest to influenza B (85.4 %). In the post-epidemic season of 2018–2019, the immune layer to influenza A(H1N1) pdm09 virus did not change significantly, which could indicate the preservation of the activity of this virus in the adult population; an increase in the immune layer of individuals with protective titers of antibodies to influenza A(H3N2) – 67.4 % and a decrease in influenza B virus – 49.2 %. A comparison of the results of laboratory data carried out in the pre- and post-epidemic seasons revealed significant differences in the number of people with average antibody titers against influenza A(H3N2) and B viruses (p < 0.05).


JMS SKIMS ◽  
2019 ◽  
Vol 22 (2) ◽  
Author(s):  
Syed Mudasir Qadri

Acute respiratory tract infection accompanying systemic symptoms are fever, malaise, coryza and myalgia. It is caused by influenza virus belonging to the orthomyxoviridae group. Three types of Influenza viruses occur in humans i.e. Influenza A, B and C All the known pandemics were caused by influenza A strains as it is known to change its genetic makeup by antigenic “shift” and “drift”. Influenza B is comparatively a genetically stable virus without any animal reservoir and Influenza C causes a milder disease. There is one more type, influenza D which occurs exclusively in cattle. The type A viruses are further divided into various subtypes based on the hemagglutinin “H” and neuraminidase “N” antigen expressed on their surface. There are 18 subtypes of hemagglutinin and 11 subtypes of neuraminidase. Influenza epidemics affect 10-20% of the global population on an average each year and are typically the result of minor antigenic variations of the virus or antigenic drift, which occur often in influenza A virus. On the other hand, pandemics which are associated with higher mortality appear at longer and varying intervals (often many decades) as a consequence of major genetic reassortment of the virus (antigenic shift) or adaptation of an avian or swine virus to humans (as with the pandemic H1N1 virus of 1918).


Author(s):  
M.E. Ignat’eva ◽  
I.Yu. Samoilova ◽  
L.V. Budatsyrenova ◽  
T.V. Korita ◽  
O.E. Trotsenko

We analyzed the epidemiological situations on influenza and acute respiratory viral infections during the 2015–2016, 2016–2017 and 2017–2018 epidemic seasons in the Republic of Sakha (Yakutia). The 2015–2016 and 2016–2017 epidemic seasons differed from the previous ones by a rather high intensity of the epidemic process, moderate duration of the epidemic awareness with a two-wave pattern of the course, high morbidity of the population at the epidemic peak and the absence of the disease’s severe forms in those vaccinated against influenza. During the 2015–2016 epidemic season, the influenza A (H1N1) virus was the dominant pathogen in Yakutia. During the 2016–2017 epidemic season, the first morbidity awareness was caused by the influenza A (H3N2) virus, the second morbidity awareness was caused by the influenza B virus. In contrast to previous two seasons the 2017–2018 epidemic season is characterized by lower intensity, a significant morbidity decrease of influenza and acute respiratory viral infections in different age groups of the population and a low level of influenza viruses' circulation. Influenza A (H3N2) virus dominated and joined influenza B virus circulation was registered subsequently during the 2017–2018 epidemic season.


2007 ◽  
Vol 14 (8) ◽  
pp. 1050-1052 ◽  
Author(s):  
Young Yoo ◽  
Jang Wook Sohn ◽  
Dae Won Park ◽  
Jeong Yeon Kim ◽  
Hye Kyung Shin ◽  
...  

ABSTRACT The performance of the SD Bioline rapid antigen test kit for influenza virus detection was evaluated with 295 respiratory specimens during the influenza season. The overall sensitivity and specificity of the SD Bioline test were 61.9% and 96.8% for the influenza A virus antigen and 54.5% and 100% for the influenza B virus antigen, respectively. The results were consistent with peak influenza activities.


1995 ◽  
Vol 115 (3) ◽  
pp. 591-601 ◽  
Author(s):  
S. Nakajima ◽  
F. Nishikawa ◽  
K. Nakamura ◽  
K. Nakajima

SummaryThe epidemiology of influenza A in Japan was studied during 1979–91 and viruses isolated from reinfections during 1983–91 were analysed, Of 2963 influenza viruses isolated during this period, 922 and 1006 were influenza A(H1N1) and A(H3N2) viruses respectively; the others were influenza B viruses. Influenza A(H1N1) and A(H3N2) caused 5 and 6 epidemics respectively, most accompanied by antigenic drift. Seventeen reinfections with H1N1 and 17 with H3N2 were detected during our study. The primary and reinfection strains isolated from 7 H1N1 and 10 H3N2 cases were studied by haemagglutination-inhibition, and amino acid and nucleotide sequences of the HA1 region of the haemagglutinin. Most of the primary and reinfection strains were antigenically and genetically similar to the epidemic viruses circulating at that time. However, in 4 out of 10 cases of reinfection with influenza H3N2 virus, reinfection strains were genetically different from the epidemic viruses.


2016 ◽  
Vol 21 (42) ◽  
Author(s):  
Norio Sugaya ◽  
Masayoshi Shinjoh ◽  
Chiharu Kawakami ◽  
Yoshio Yamaguchi ◽  
Makoto Yoshida ◽  
...  

The 2014/15 influenza season in Japan was characterised by predominant influenza A(H3N2) activity; 99% of influenza A viruses detected were A(H3N2). Subclade 3C.2a viruses were the major epidemic A(H3N2) viruses, and were genetically distinct from A/New York/39/2012(H3N2) of 2014/15 vaccine strain in Japan, which was classified as clade 3C.1. We assessed vaccine effectiveness (VE) of inactivated influenza vaccine (IIV) in children aged 6 months to 15 years by test-negative case–control design based on influenza rapid diagnostic test. Between November 2014 and March 2015, a total of 3,752 children were enrolled: 1,633 tested positive for influenza A and 42 for influenza B, and 2,077 tested negative. Adjusted VE was 38% (95% confidence intervals (CI): 28 to 46) against influenza virus infection overall, 37% (95% CI: 27 to 45) against influenza A, and 47% (95% CI: -2 to 73) against influenza B. However, IIV was not statistically significantly effective against influenza A in infants aged 6 to 11 months or adolescents aged 13 to 15 years. VE in preventing hospitalisation for influenza A infection was 55% (95% CI: 42 to 64). Trivalent IIV that included A/New York/39/2012(H3N2) was effective against drifted influenza A(H3N2) virus, although vaccine mismatch resulted in low VE.


2013 ◽  
Vol 142 (5) ◽  
pp. 933-939 ◽  
Author(s):  
A. DE DONNO ◽  
A. IDOLO ◽  
M. QUATTROCCHI ◽  
A. ZIZZA ◽  
G. GABUTTI ◽  
...  

SUMMARYThe aim of this study was to evaluate the presence of influenza virus co-infections in humans and changes in the genetic variability of A(H3N2) virus strains in southern Italy from 1999 to 2009. A partial sequence of the haemagglutinin (HA) gene by human influenza H3N2 strains identified in oropharyngeal swabs from patients with influenza-like illness was analysed by DNA sequencing and a phylogenetic analysis was performed. During the seasons 1999–2000, 2002–2003, 2004–2005 and 2008–2009, the influenza viruses circulating belonged to subtype H3N2. However, A(H1N1) subtype virus and B type were respectively prevalent during the 2000–2001, 2006–2007, 2007–2008 and 2001–2002, 2003–2004, 2005–2006 seasons. The HA sequences appeared to be closely related to the sequence of the influenza A vaccine strain. Only the 2002–2003 season was characterized by co-circulation of two viral lineages: A/New York/55/01(H3N2)-like virus of the previous season and A/Fujian/411/02(H3N2)-like virus, a new H3 variant. In this study, over the decade analysed, no significant change was seen in the sequences of the HA gene of H3 viruses isolated.


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