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.
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.