Influenza

Surveillance of seasonal influenza

The ICDC is responsible for the ongoing surveillance of seasonal influenza in Israel.
The aim of influenza surveillance is to create an updated picture on influenza activity. The information is utilized by the health ministry administration in the process of decision making, and is an important source of information for the medical community, the media and the general public.
A national surveillance system was set up in the early 2000's based mainly on administrative data collected routinely by the health system (such as primary care physician visits and emergency room visits).
Surveillance of influenza is based on two modalities: clinical and laboratory surveillance.
Clinical surveillance comprises the collection and analysis of data on patient visits to community clinics and hospital emergency rooms.

Community data: Data from the two largest HMO's (Maccabi and Clalit) on patients diagnosed with influenza, influenza-like illness, upper respiratory infection or pneumonia are transferred to the ICDC on a daily basis.
Hospital data: Daily aggregated data are received from hospital ER's, on visits of patients (adults and children) diagnosed with pneumonia or acute upper respiratory infection. In addition, daily data are collected on bed occupancy rates in internal and pediatric wards (based on the Ministry of Health database), and on mortality from pneumonia as well as all-cause mortality.

A sentinel network of outpatient clinics distributed throughout Israel. This network, established by the ICDC in 1996, supplies data based on nasopharyngeal specimens of a sample of patients presenting with influenza-like symptoms. The specimens are analysed by the central virology laboratory of the Ministry of Health, and the ICDC receives weekly reports on positive identifications of influenza and RSV.
Sheba Medical Center: weekly data on influenza and other respiratory viruses detected among hospitalized patients.

The clinical and laboratory data are analysed and summarized in weekly reports, in Hebrew and English, which are published on the website of the ICDC.
An annual summary report of influenza activity is also available on the ICDC website in Hebrew and English.