Wisconsin influenza activity is declining. Influenza A has been the dominant strain so far in Wisconsin, but the relative proportion of influenza B is increasing. Also, we are detecting more severe ARI in individuals with human metapneumovirus.
As of March 3, 2017, there had been 5,904 influenza-related hospitalizations since September 1, 2017; 65% of hospitalizations have been in individuals aged ≥65 years. There have been 742 admissions to ICUs, 58% were aged ≥65 years; and there have been 212 cases requiring mechanical ventilation, 54% aged ≥65 years. This level is well above last year at this time, and above the 4,546 hospitalizations reported at this time in 2014-2015.
The prevalence of influenza-like illness [fever of 100oF or higher and either cough or sore throat] in Wisconsin's primary care patients is at 2.5% and is declining.
9.8% of last week's primary care patients had all-cause respiratory infections.
The prevalence of acute diarrheal illness (ADI) in Wisconsin's primary care patients is at 1.5%
The most commonly identified viral cause of Acute Respiratory infections (ARI) in Wisconsin is Influenza A. Over the past 4 weeks the typical ARI case presenting for primary care has been 34.1 years old and 61% of patients have been female. 63% of patients identified a sick contact 1-to-3 days before illness onset and typically present to the clinic 3.5 days after illness onset. 36% of illnesses are characterized as mild, with 57% having moderate symptoms and 3% having severe symptoms.
|Typical Symptoms||Percent||Viruses in Circulation||Percent|
Antivirals need to be started with 48 hours of symptom onset to be effective against influenza
Antivirals started after 48 hours may be effective for hospitalized patients with confirmed influenza
For the 2017-2018 season to date (last week):
For up to date information, visit the zika page on CDC.
* The weekly influenza update is adapted from an email from Jon Temte, MD, PhD; Chair, Wisconsin Council on Immunization Practices; Professor, Department of Family Medicine and Community Health, University of Wisconsin School of Medicine and Public Health.