The complex non-linear associations of climate variability with seasonal influenza transmission in Shanghai, China

Abstract School closures are considered as a potential nonpharmaceutical intervention to mitigate severe influenza epidemics and pandemics. In this study, we assessed the effects of scheduled school closure on influenza transmission using influenza surveillance data before, during, and after spring breaks in South Korea, 2014–2016. During the spring breaks, influenza transmission was reduced by 27%–39%, while the overall reduction in transmissibility was estimated to be 6%–23%, with greater effects observed among school-aged children.

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Masks in a Post COVID-19 World: A Better Alternative to Curtailing Influenza?

10.1101/2021.07.03.21259943 ◽

2021 ◽

Author(s):

Henri Froese ◽

Angel G. A. Prempeh

Keyword(s):

Respiratory Diseases ◽

Seasonal Influenza ◽

Transmission Rate ◽

Model Fit ◽

Respiratory Specimen ◽

The Past ◽

Hypothetical Scenario ◽

Influenza Transmission ◽

Influenza Vaccinations ◽

The Impact

Over the course of the coronavirus pandemic, it has become apparent that non-pharmaceutical interventions such as masks and social distancing are of great help in mitigating the transmission of airborne infectious diseases. Additionally, data from respiratory specimen analysis from the past year show that current mask mandates established for COVID-19 have inadvertently reduced the rates of other respiratory diseases, including influenza. Thus, the question arises as to whether comparatively mild measures should be kept in place after the pandemic to reduce the impact of influenza. In this study, we employed a series of differential equations to simulate past influenza seasons, assuming people wore face masks. This was achieved by introducing a variable to account for the efficacy and prevalence of masks and then analyzing its impact on influenza transmission rate in an SEIR model fit to the actual past seasons. We then compared influenza rates in this hypothetical scenario with the actual rates over the seasons. Our results show that several combinations of mask efficacy and prevalence can significantly reduce the burden of seasonal influenza. Particularly, our simulations suggest that a minority of individuals wearing masks greatly reduce the number of influenza infections. Considering the efficacy rates of masks and the relatively insignificant monetary cost, we highlight that it may be a viable alternative or complement to influenza vaccinations. We conclude with a brief discussion of our results and other practical aspects.

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Successful interruption of seasonal influenza transmission under the COVID-19 rapid response in Zhejiang Province, China

Public Health ◽

10.1016/j.puhe.2020.10.011 ◽

2020 ◽

Vol 189 ◽

pp. 123-125

Author(s):

W. Cheng ◽

Z. Yu ◽

S. Liu ◽

W. Sun ◽

F. Ling ◽

...

Keyword(s):

Seasonal Influenza ◽

Zhejiang Province ◽

Rapid Response ◽

Influenza Transmission

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The complex associations of climate variability with seasonal influenza A and B virus transmission in subtropical Shanghai, China

The Science of The Total Environment ◽

10.1016/j.scitotenv.2019.134607 ◽

2020 ◽

Vol 701 ◽

pp. 134607 ◽

Cited By ~ 4

Author(s):

Yuzhou Zhang ◽

Chuchu Ye ◽

Jianxing Yu ◽

Weiping Zhu ◽

Yuanping Wang ◽

...

Keyword(s):

Climate Variability ◽

Influenza A ◽

Seasonal Influenza ◽

Virus Transmission ◽

B Virus

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Predicting seasonal influenza transmission using functional regression models with temporal dependence

PLoS ONE ◽

10.1371/journal.pone.0194250 ◽

2018 ◽

Vol 13 (4) ◽

pp. e0194250 ◽

Cited By ~ 2

Author(s):

Manuel Oviedo de la Fuente ◽

Manuel Febrero-Bande ◽

María Pilar Muñoz ◽

Àngela Domínguez

Keyword(s):

Regression Models ◽

Seasonal Influenza ◽

Functional Regression ◽

Temporal Dependence ◽

Influenza Transmission ◽

Functional Regression Models

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Cost-effectiveness of influenza control measures: a dynamic transmission model-based analysis

Epidemiology and Infection ◽

10.1017/s0950268813000423 ◽

2013 ◽

Vol 141 (12) ◽

pp. 2581-2594 ◽

Cited By ~ 7

Author(s):

S.-C. CHEN ◽

C.-M. LIAO

Keyword(s):

Cost Effectiveness ◽

Natural Ventilation ◽

Seasonal Influenza ◽

School Setting ◽

Control Measures ◽

Transmission Model ◽

Model Based ◽

Dynamic Transmission Model ◽

Influenza Transmission ◽

The Cost

SUMMARYWe investigated the cost-effectiveness of different influenza control strategies in a school setting in Taiwan. A susceptible-exposure-infected-recovery (SEIR) model was used to simulate influenza transmission and we used a basic reproduction number (R0)–asymptomatic proportion (θ) control scheme to develop a cost-effectiveness model. Based on our dynamic transmission model and economic evaluation, this study indicated that the optimal cost-effective strategy for all modelling scenarios was a combination of natural ventilation and respiratory masking. The estimated costs were US$10/year per person in winter for one kindergarten student. The cost for hand washing was estimated to be US$32/year per person, which was much lower than that of isolation (US$55/year per person) and vaccination (US$86/year per person) in containing seasonal influenza. Transmission model-based, cost-effectiveness analysis can be a useful tool for providing insight into the impacts of economic factors and health benefits on certain strategies for controlling seasonal influenza.

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Increased urbanization reduced the effectiveness of school closures on seasonal influenza epidemics in China

Infectious Diseases of Poverty ◽

10.1186/s40249-021-00911-7 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Hao Lei ◽

Hangjin Jiang ◽

Nan Zhang ◽

Xiaoli Duan ◽

Tao Chen ◽

...

Keyword(s):

Seasonal Influenza ◽

Southern China ◽

Social Contact ◽

School Closure ◽

Surveillance Data ◽

Reproductive Number ◽

Influenza Surveillance ◽

Sirs Model ◽

Influenza Transmission ◽

The Impact

Abstract Background School closure is a common mitigation strategy during severe influenza epidemics and pandemics. However, the effectiveness of this strategy remains controversial. In this study, we aimed to explore the effectiveness of school closure on seasonal influenza epidemics in provincial-level administrative divisions (PLADs) with varying urbanization rates in China. Methods This study analyzed influenza surveillance data between 2010 and 2019 provided by the Chinese National Influenza Center. Taking into consideration the climate, this study included a region with 3 adjacent PLADs in Northern China and another region with 4 adjacent PLADs in Southern China. The effect of school closure on influenza transmission was evaluated by the reduction of the effective reproductive number of seasonal influenza during school winter breaks compared with that before school winter breaks. An age-structured Susceptible-Infected-Recovered-Susceptible (SIRS) model was built to model influenza transmission in different levels of urbanization. Parameters were determined using the surveillance data via robust Bayesian method. Results Between 2010 and 2019, in the less urbanized provinces: Hebei, Zhejiang, Jiangsu and Anhui, during school winter breaks, the effective reproductive number of seasonal influenza epidemics reduced 14.6% [95% confidential interval (CI): 6.2–22.9%], 9.6% (95% CI: 2.5–16.6%), 7.3% (95% CI: 0.1–14.4%) and 8.2% (95% CI: 1.1–15.3%) respectively. However, in the highly urbanized cities: Beijing, Tianjin and Shanghai, it reduced only 5.2% (95% CI: -0.7–11.2%), 4.1% (95% CI: -0.9–9.1%) and 3.9% (95% CI: -1.6–9.4%) respectively. In China, urbanization is associated with decreased proportion of children and increased social contact. According to the SIRS model, both factors could reduce the impact of school closure on seasonal influenza epidemics, and the proportion of children in the population is thought to be the dominant influencing factor. Conclusions Effectiveness of school closure on the epidemics varies with the age structure in the population and social contact patterns. School closure should be recommended in the low urbanized regions in China in the influenza seasons. Graphical abstract

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Preventive and protective measures reducing influenza transmission in general practice: a systematic review

BJGP Open ◽

10.3399/bjgpopen19x101657 ◽

2019 ◽

Vol 3 (3) ◽

pp. bjgpopen19X101657 ◽

Cited By ~ 3

Author(s):

Philipp Suter ◽

Tessa Kermode ◽

Carole Clair ◽

Yolanda Mueller ◽

Nicolas Senn

Keyword(s):

Systematic Review ◽

Seasonal Influenza ◽

Controlled Trial ◽

Influenza Infection ◽

Experimental Studies ◽

Cochrane Central Register ◽

Protective Measures ◽

Protection Measures ◽

Influenza Transmission ◽

The Impact

BackgroundSeasonal influenza and influenza-like illnesses are widespread, with an impact on GP consultations. GPs apply many preventive and protective measures to prevent seasonal influenza transmission, with no clear evidence of their effectiveness in this setting.AimTo review the effectiveness of preventive and protective measures to reduce the transmission of seasonal influenza and influenza-like illnesses in GP practices.Design & settingA systematic review was conducted of the literature in Medline, Embase, and the Cochrane Central Register databases published between January 1960 and April 2014, later extended to January 2018.MethodPreferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria were used. Controlled trials and experimental studies were included. Study quality was assessed according to the Cochrane risk of bias tool.ResultsOut of 5727 articles screened, only two studies were finally retained: one study about the seasonal influenza vaccination of GPs to prevent transmission from patients or staff, and one about surface disinfection. The first study was a controlled trial, which showed limited evidence for seasonal influenza infection reduction among GPs through vaccination. The second, an experimental study, performed a virus screening on toys in the waiting area before and after disinfection. No study on protection measures was found that assessed the impact on influenza transmission in general practices.ConclusionThe evidence is scarce on interventions that reduce influenza transmission in GP practices.

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Modeling and Predicting Seasonal Influenza Transmission in Warm Regions Using Climatological Parameters

PLoS ONE ◽

10.1371/journal.pone.0009450 ◽

2010 ◽

Vol 5 (3) ◽

pp. e9450 ◽

Cited By ~ 100

Author(s):

Radina P. Soebiyanto ◽

Farida Adimi ◽

Richard K. Kiang

Keyword(s):

Seasonal Influenza ◽

Influenza Transmission

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Reduction of Seasonal Influenza Transmission among Healthcare Workers in an Intensive Care Unit: A 4-Year Intervention Study in Thailand

Infection Control and Hospital Epidemiology ◽

10.1086/656565 ◽

2010 ◽

Vol 31 (10) ◽

pp. 996-1003 ◽

Cited By ~ 9

Author(s):

Anucha Apisarnthanarak ◽

Timothy M. Uyeki ◽

Pilaipan Puthavathana ◽

Rungrueng Kitphati ◽

Linda M. Mundy

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Healthcare Workers ◽

Seasonal Influenza ◽

Care Center ◽

Antiviral Treatment ◽

Tertiary Care ◽

Economic Benefits ◽

Community Acquired Pneumonia ◽

Influenza Transmission

Objective.To evaluate the feasibility and effectiveness of an influenza control bundle to minimize healthcare-associated seasonal influenza transmission among healthcare workers (HCWs) in an intensive care unit (ICU) equipped with central air conditioning.Methods.A quasi-experimental study was conducted in a 500-bed tertiary care center in Thailand from July 1, 2005, through June 30, 2009. The medical ICU (MICU) implemented an influenza control bundle including healthcare worker (HCW) education, influenza screening of adult community-acquired pneumonia patients, antiviral treatment of patients and ill HCWs who tested positive for influenza, promotion of influenza vaccination among HCWs, and reinforcement of standard infection control policies. The surgical ICU (SICU) and coronary care unit (CCU) received no intervention.Results.The numbers of influenza infections among HCWs during the pre- and postintervention periods were 18 cases in 5,294 HCW-days and 0 cases in 5,336 HCW-days in the MICU (3.4 vs 0 cases per 1,000 HCW-days; P < .001), 19 cases in 4,318 HCW-days and 20 cases in 4,348 HCW-days in the SICU (4.4 vs 4.6 cases per 1,000 HCW-days; P = .80), and 18 cases in 5,000 HCW-days and 18 cases in 5,143 HCW-days in the CCU (3.6 vs 3.5 cases per 1,000 HCW-days; P = .92), respectively. Outbreak-related influenza occurred in 7 MICU HCWs, 6 SICU HCWs, and 4 CCU HCWs before intervention and 0 MICU HCWs, 9 SICU HCWs, and 8 CCU HCWs after intervention. Before and after intervention, 25 (71%) and 35 (100%) of 35 MICU HCWs were vaccinated, respectively (P < .001); HCW vaccination coverage did not change significantly in the SICU (21 [70%] of 30 vs 24 [80%] of 30; P = .89) and CCU (19 [68%] of 28 vs 21 [75%] of 28; P = .83). The estimated costs of US $6,471 per unit for postintervention outbreak investigations exceeded the intervention costs of US $4,969.Conclusion.A sustained influenza intervention bundle was associated with clinical and economic benefits to a Thai hospital.

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