Weekly U.S. Influenza Surveillance Report

CDC's Influenza Division produces a weekly influenza surveillance report, FluView. According to this week's report (Oct 28- Nov 3), seasonal influenza activity is at levels below baseline in the United States.

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Synopsis:

Influenza activity in the United States remains low, although small increases in activity were reported. Influenza A(H1N1)pdm09, influenza A(H3N2), and influenza B viruses continue to co-circulate, with influenza A(H1N1)pdm09 viruses reported most commonly by public health laboratories since September 30, 2018. Below is a summary of the key influenza indicators for the week ending November 3, 2018:

Viral Surveillance: Influenza A viruses have predominated in the United States since the beginning of July. The percentage of respiratory specimens testing positive for influenza in clinical laboratories was low.

Virus Characterization:The majority of influenza viruses characterized antigenically and genetically are similar to the cell-grown reference viruses representing the 2018–2019 Northern Hemisphere influenza vaccine viruses.
Antiviral Resistance:All viruses tested since late May show susceptibility to the antiviral drugs oseltamivir, zanamivir, and peramivir.

Influenza-like Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) increased slightly to 1.8%, which is below the national baseline of 2.2%. One of 10 regions reported ILI at or above their region-specific baseline level.

ILI State Activity Indictor Map: One state experienced moderate ILI activity, three states experienced low ILI activity; and New York City, the District of Columbia, Puerto Rico and 46 states experienced minimal ILI activity.

Geographic Spread of Influenza:The geographic spread of influenza in two states was reported as regional; Guam and six states reported local activity; the District of Columbia, Puerto Rico, the U.S. Virgin Islands and 40 states reported sporadic activity; and two states reported no activity.
Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the system-specific epidemic threshold in the National Center for Health Statistics (NCHS) Mortality Surveillance System.
Influenza-associated Pediatric Deaths: No influenza-associated pediatric deaths were reported to CDC for week 44.