The ALERT Algorithm: How to Simply Define a Period of Elevated Disease Incidence

Despite the number of infections, hospitalizations, and deaths from influenza each year, developing the ability to predict the timing of these outbreaks has remained elusive. Public health practitioners have lacked a reliable, easy-to-implement method for predicting the onset of a period of elevated influenza incidence in a community. We (a team of statisticians, epidemiologists, and clinicians) have developed a model to help public health practitioners develop simple, adaptable, data-driven rules to define a period of increased disease incidence in a given location.

May 02, 2019

The Evolution of the WHO/NREVSS Influenza Surveillance System: The Challenges and Opportunities that Accompany Electronic Laboratory Data

The Influenza Division (ID) in the Centers for Disease Control and Prevention (CDC) maintains the WHO/NREVSS surveillance system, a network of laboratories in the U.S. that report influenza testing results. This system has seen many changes during the past 40 years, especially since the 2009 H1N1 pandemic. This was due in large part to increased adoption of HL7 messaging via PHLIP. PHLIP data is detailed, standardized influenza testing information, reported in near real-time.

May 02, 2019

The Growth and Variation of Symptoms of Influenza-like Illness: An Application of the Linear Growth Curve Model in Syndromic Surveillance in Rural China

Symptoms of influenza-like illness (ILI) were reported daily by health workers via the integrated syndromic surveillance system in rural China (ISSC)(1).


To analyze the growth and variation of ILI reports using individual growth curve model.

May 02, 2019

Evaluation of the Influenza Sentinel Surveillance System in Singapore 2011-2012

MOH's national sentinel surveillance programme for influenza is part of the WHO international laboratory-based surveillance network to detect the emergence and spread of new antigenic variants of influenza viruses. Virological sample collection is on-going and is carried out during both outbreak and non-outbreak periods.In 2011 and 2012, the sentinel surveillance programme involved a total of 169 sites (18 government primary care clinics and 151 private/general practitioner [GP] clinics).


April 28, 2019

Two-stage Approach for Detecting Aberration of Influenza-like Illness

Pandemic 2009 H1N1 influenza and recent H7N9 influenza outbreaks made the public aware of the threat of influenza infection. In fact, annual influenza epidemic caused heavy disease burden and high economic loss around the world [1, 2]. Although the virological surveillance provided the high sensitivity and specificity for testing results, the timeliness and the cost of the test were not feasible for extensive public health surveillance. In addition, traditional sentinel physician surveillance also encountered many challenges such as the representativeness and reporting bias.

May 02, 2019

Influenza Sentinel Surveillance in Lagos State Nigeria, 2009 _ 2011

Outbreaks of Avian influenza (AI) in poultry were first reported in Nigeria in 2006 (1). The only human case was reported in 2007 (1). The epizootics of AI among poultry and wild birds and subsequent risk to human health highlighted the need to detect influenza viruses with pandemic potential and for establishment of Influenza Sentinel Surveillance (ISS) System.

April 28, 2019

Under-ascertainment of Illness due to Influenza in Administrative Databases, a Population-based Record Linkage Study

Under-ascertainment of severe outcomes of influenza infections in administrative databases has long been recognised. After reviewing registered deaths following an influenza epidemic in 1847, William Farr, of the Registrar-General's Office, London, England, commented: ''the epidemic carried off more than 5,000 souls over and above the mortality of the season, the deaths referred to that cause [influenza] are only 1,157"[1].

May 02, 2019

Influenza Surveillance in the Department of Veterans Affairs (VA): 2012-2013 Influenza Season

Influenza is associated with significant morbidity and mortality nationally each year and VA's large elderly population is at particular risk. VA Office of Public Health (OPH) has monitored influenza and influenza-like-illness (ILI) activity using the VA's biosurveillance system since 2009 (1,2). VA influenza surveillance capacity has expanded significantly in recent years to include inpatient influenza data, telephone triage data, laboratory testing data and enhanced geospatial mapping capabilities.


April 28, 2019

Multiple Surveillance Systems Track an Active Flu Season

Each season in the United States a multi-component influenza surveillance system monitors and describes influenza activity. This presentation will describe the overall picture of influenza virus circulation and compare data from each of the surveillance components to previous years to better understand what turned out to be a season with high levels of activity. Also, to provide a global context for this season, data from the U.S. will be compared to other Northern Hemisphere countries, and a selection of vaccine strains for the 2013-2014 will be covered.

September 28, 2017

ILI and SARI Surveillance along the California & Arizona Borders with Mexico, 2011-12

National borders do not prevent the transmission of pathogens and associated vectors among border populations. The Naval Health Research Center (NHRC) has collaborated with the Mexican Secretariat of Health, the U. S. Department of State’s Biosecurity Engagement Program (BEP) and the U. S. Centers for Disease Control and Prevention (CDC) in concert with local health officials to conduct ILI surveillance (since 2004) and SARI surveillance (since 2009) in the border region.


May 17, 2018


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