Assessment of two complementary influenza surveillance systems: sentinel primary care influenza-like illness versus severe hospitalized laboratory-confirmed influenza using the moving epidemic method

Torner, Núria; Basile, Luca; Martı́nez, Ana; Rius, Cristina; Godoy, Pere; Jané, Mireia; Domı́nguez, Àngela

doi:10.1186/s12889-019-7414-9

Cited by 17 publications

(22 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For this purpose, a simple method proposed by the WHO was used [22,29,30]. WHO is now recommending MEM, which is a more sophisticated method of reporting influenza activity adopted by the European Centre for Disease Prevention and Control [31][32][33][34] and adopted by several countries from other regions [35,36]. The analysis using the MEM application with 11 seasons of syndromic surveillance data showed clear seasonality to ILI activity and visual inspection of graphed data revealed a single seasonal peak per year.…”

Section: Discussionmentioning

confidence: 99%

Establishing seasonal and alert influenza thresholds in Morocco

et al. 2020

View full text Add to dashboard Cite

Background: Several statistical methods of variable complexity have been developed to establish thresholds for influenza activity that may be used to inform public health guidance. We compared the results of two methods and explored how they worked to characterize the 2018 influenza season performance-2018 season. Methods: Historical data from the 2005/2006 to 2016/2018 influenza season performance seasons were provided by a network of 412 primary health centers in charge of influenza like illness (ILI) sentinel surveillance. We used the WHO averages and the moving epidemic method (MEM) to evaluate the proportion of ILI visits among all outpatient consultations (ILI%) as a proxy for influenza activity. We also used the MEM method to evaluate three seasons of composite data (ILI% multiplied by percent of ILI with laboratory-confirmed influenza) as recommended by WHO. Results: The WHO method estimated the seasonal ILI% threshold at 0.9%. The annual epidemic period began on average at week 46 and lasted an average of 18 weeks. The MEM model estimated the epidemic threshold (corresponding to the WHO seasonal threshold) at 1.5% of ILI visits among all outpatient consultations. The annual epidemic period began on week 49 and lasted on average 14 weeks. Intensity thresholds were similar using both methods. When using the composite measure, the MEM method showed a clearer estimate of the beginning of the influenza epidemic, which was coincident with a sharp increase in confirmed ILI cases. Conclusions: We found that the threshold methodology presented in the WHO manual is simple to implement and easy to adopt for use by the Moroccan influenza surveillance system. The MEM method is more statistically sophisticated and may allow a better detection of the start of seasonal epidemics. Incorporation of virologic data into the composite parameter as recommended by WHO has the potential to increase the accuracy of seasonal threshold estimation.

show abstract

Section: Discussionmentioning

confidence: 99%

Establishing seasonal and alert influenza thresholds in Morocco

et al. 2020

View full text Add to dashboard Cite

show abstract

“…For this purpose, a simple method proposed by the WHO was used (21)(22)(23). WHO is now recommending MEM, which is a more sophisticated method of reporting in uenza activity adopted by the European Centre for Disease Prevention and Control (40-43) and adopted by several countries from other regions (34,44). The analysis using the MEM application with eleven seasons of syndromic surveillance data showed clear seasonality to ILI activity and visual inspection of graphed data revealed a single seasonal peak per year.…”

Section: Discussionmentioning

confidence: 99%

“…MEM was rst used in in the WHO European Region to estimate epidemic period and intensity using a minimum of ve historical seasons for the calculations and the target season (28). Despite the availability of only three years of virologic data in Morocco, we followed a WHO recommendation to use the composite parameter with MEM (44). This allowed a clearer cut estimation of the beginning of the in uenza epidemic period, characterized by a sharp increase in in uenza-con rmed ILI cases.…”

Section: Discussionmentioning

confidence: 99%

Establishing seasonal and alert influenza thresholds in Morocco

Rguig

Cherkaoui²,

McCarron³

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract Background: Several statistical methods of variable complexity have been developed to establish thresholds for influenza activity that may be used to inform public health guidance. We compared the results of two methods and explored how they worked to characterize the 2017-2018 season.Methods: Historical data from the 2005/2006 to 2016/2017 seasons were provided by a network of 412 primary health centers in charge of influenza like illness (ILI) sentinel surveillance. We used the WHO averages and the moving epidemic method (MEM) to evaluate the proportion of ILI visits among all outpatient consultations (ILI%) as a proxy for influenza activity. We also used the MEM method to evaluate three seasons of composite data (ILI% multiplied by percent of ILI with laboratory-confirmed influenza) as recommended by WHO. Results: The WHO method estimated the seasonal ILI% threshold at 0.9%. The annual epidemic period began on average at week 46 and lasted an average of 18 weeks. The MEM model estimated the epidemic threshold (corresponding to the WHO seasonal threshold) at 1.5% of ILI visits among all outpatient consultations. The annual epidemic period began on week 49 and lasted on average 14 weeks. Intensity thresholds were similar using both methods. When using the composite measure, the MEM method showed a clearer estimate of the beginning of the influenza epidemic, which was coincident with a sharp increase in confirmed ILI cases. Conclusions: We found that the threshold methodology presented in the WHO manual is simple to implement and easy to adopt for use by the Moroccan influenza surveillance system. The MEM method is more statistically sophisticated and may allow a better detection of the start of seasonal epidemics. Incorporation of virologic data into the composite parameter as recommended by WHO has the potential to increase the accuracy of seasonal threshold estimation.

show abstract

“…For this purpose, a simple method proposed by the WHO was used (21)(22)(23). WHO is now recommending MEM, which is a more sophisticated method of reporting influenza activity adopted by the European Centre for Disease Prevention and Control (40)(41)(42)(43) and adopted by several countries from other regions (34,44). The analysis using the MEM application witheleven seasons of syndromic surveillance data showed clear seasonality toILI activity and visual inspection of graphed data revealed a single seasonal peak per year.…”

Section: Discussionmentioning

confidence: 99%

Establishing seasonal and alert influenza thresholds in Morocco

Rguig

Cherkaoui²,

McCarron³

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract Background: Several statistical methods of variable complexity have been developed to establish thresholds for influenza activity to inform public health guidance. We compared the results of two methods and explored how they worked to characterize the 2017-2018 season.Methods: Historical data from the 2005/2006 to 2016/2017 seasons were provided by a network of 412 primary health centers in charge of influenza like illness (ILI) sentinel surveillance. We used the WHO averages and the moving epidemic method (MEM) to evaluate the proportion of ILI visits among all outpatient consultations (ILI%) as a proxy for influenza activity. We also used the MEM method to evaluate three seasons of composite data (ILI% multiplied by percent of ILI with laboratory-confirmed influenza) as recommended by WHO.Results: The WHO method estimated the seasonal ILI% threshold at 0.9%. The annual epidemic period begins on average at week 46 and lasts an average of 18 weeks. The MEM model estimated the epidemic threshold (corresponding to the WHO seasonal threshold) at 1.5% of ILI visits among all consultations. The annual epidemic period began on week 49 and lasted on average 14 weeks. Intensity thresholds were similar using both methods. When using the composite measure, the MEM method showed a clearer estimate of the beginning of the influenza epidemic, which was coincident with a sharp increase in confirmed ILI cases.Conclusions: We found that the threshold methodology presented in the WHO manual is simple to implement and easy to adopt for use by the Moroccan influenza surveillance system. The MEM method is more statistically sophisticated and may allow a better detection of the start of seasonal epidemics. Incorporation of virologic data into the composite parameter as recommended by WHO has the potential to increase the accuracy of seasonal threshold estimation.

show abstract

Assessment of two complementary influenza surveillance systems: sentinel primary care influenza-like illness versus severe hospitalized laboratory-confirmed influenza using the moving epidemic method

Cited by 17 publications

References 20 publications

Establishing seasonal and alert influenza thresholds in Morocco

Establishing seasonal and alert influenza thresholds in Morocco

Establishing seasonal and alert influenza thresholds in Morocco

Establishing seasonal and alert influenza thresholds in Morocco

Contact Info

Product

Resources

About