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Background: The burden of influenza in primary care is difficult to assess, since most patients with symptoms of a respiratory infection are not tested. The case definition of "medically attended acute respiratory infection" (MAARI) in the German physician sentinel is sensitive; however, it requires modelling techniques to derive estimates of disease attributable to influenza and respiratory syncytial virus (RSV). Objectives: The objective of this paper was to review and extend our previously published model in order to estimate the burden of RSV and the differential burden of the two influenza B lineages (Victoria, Yamagata) as well as both influenza A subtypes on primary care visits. Methods: Data on MAARI and virological results of respiratory samples (virological sentinel) were available from 2010/11 until 2017/18. We updated the previously published generalized additive regression model to include RSV. Results: We found that the proportion of MAARI due to RSV is substantial only in the 0‐1‐ and 2‐4‐year‐old age groups (0‐1 years old: median 7.5%, range 4.0%‐14.8%; 2‐4 years old: median 6.5%, range 4.0%‐10.3%); in the 0‐1 years old age group, RSV leads in almost all seasons to a higher burden than any influenza type or subtype, but this is reversed in the age group 2‐4 years old. Conclusions: We succeeded in rearranging our previously published model on MAARI to incorporate RSV as well as the two influenza B lineages (Victoria, Yamagata) in the time period 2010 to 2018. [ABSTRACT FROM AUTHOR]

Please cite this paper as: Adhin et al. (2012) Trends of Influenza infection in Suriname. Influenza and Other Respiratory Viruses DOI: 10.1111/irv.12037. The trends of influenza infection in Suriname were assessed from February 2010 through February 2011. Testing of 393 patients with symptoms of acute respiratory infection (ARI) revealed 15·3% Influenza B and 18·6% could be identified as influenza A positive, consisting of 56% influenza A(H1N1)pdm09 and 44% seasonal A(H3N2). Influenza infection occurred throughout the year, and all three influenza types affected young children as the primary population. The annual incidence of A(H1N1)pdm09 was 6·88 per 100 000 inhabitants [CI] 4·87-9·45. The spread of influenza could neither be linked to tourist flow from the Netherlands nor to contact rates related to school schedules. [ABSTRACT FROM AUTHOR]

Please cite this paper as: Yang et al. (2011) Seroprevalence of pandemic (H1N1) 2009 influenza and effectiveness of 2010/2011 influenza vaccine during 2010/2011 season in Beijing, China. Influenza and Other Respiratory Viruses 6(6), 381-388. Background In the post-pandemic period, pandemic (H1N1) 2009 virus was expected to circulate seasonally and was introduced into trivalent influenza vaccine during 2010/2011 season in the Northern Hemisphere. Objectives The aim of this study was to examine the evolution of herd immunity against pandemic (H1N1) 2009 virus in Beijing, China, during 2010/2011 season and effectiveness of the 2010/2011 trivalent vaccine. Methods Two serological surveys were conducted before and after 2010/2011 season in Beijing. A case-control study was used to investigate vaccine effectiveness against influenza-like illness (ILI) and lower respiratory tract infection (LRI). Results A total of 4509 and 4543 subjects participated in the pre- and post-season surveys, respectively. The standardized seroprevalence of pandemic (H1N1) 2009 influenza increased from 22·1% pre-season to 24·3% post-season ( P < 0·001). Significant elevation in seroprevalence appeared in the ≥60 years age-group ( P < 0·001), but not in others. The 2010/2011 trivalent vaccine contributed to the higher post-seasonal seroprevalence in unvaccinated individuals ( P = 0·024), but not in those vaccinated with monovalent pandemic vaccine ( P = 0·205), as well as in those without prior immunity versus those with immunity. The adjusted effectiveness of the 2010/2011 trivalent vaccine was 79% protection against ILI (95% CI, 61-89%) and 95% against LRI (95% CI: 59-99%). Conclusions A slight increase in herd immunity against pandemic (H1N1) 2009 influenza was observed in Beijing, China, during the 2010/2011 season. Prior vaccination and immunity had a suppressive impact on immune response toward this novel influenza virus, elicited by 2010/2011 trivalent vaccine. This trivalent vaccine conferred good protection against ILI and LRI. [ABSTRACT FROM AUTHOR]