Health Information Portal (HIP)

Philadelphia Influenza Surveillance Updates: PDPH tracks influenza activity in Philadelphia, especially severe influenza disease. Providers should report all hospitalized influenza cases, influenza deaths in children, and influenza outbreaks in closed settings like long-term care facilities and shelters.

Week 1: During week 1, influenza diagnoses at local emergency departments were still seasonally elevated but decreased for all age groups. Positive detections for influenza A at select local hospital laboratories remained high but declined sharply, while detections for influenza B remained low during week 1. Eighteen influenza outbreaks in long-term care facilities have been reported and confirmed (≥ 1 case of laboratory confirmed flu reported in a long-term care facility) during the 2025-2026 season to date.

Week 1 Report: Click here to download the latest weekly report of influenza activity (January 4, 2025—January 10, 2026) in a printable format.

State and National Influenza Surveillance Updates:

Pennsylvania: As of January 10, 2026, the Pennsylvania Department of Health (PADOH) respiratory virus summaries currently list influenza activity as moderate but decreasing rapidly. Activity levels in PA are based on laboratory confirmed influenza cases. For more information, please visit: https://www.pa.gov/agencies/health/diseases-conditions/infectious-disease/respiratory-viruses/respiratory-virus-dashboard.

United States: As of January 10, 2026, the CDC reported that influenza activity is elevated across the country but has decreased or remained stable for two consecutive weeks. In week 1, clinical laboratories reported 17,574 (18.6%) of 94,649 specimens tested positive for influenza, 93.0% of which were influenza A. Of influenza A specimens subtyped at public health labs, 87.8% have been subtyped as H3N2 and 12.2% have been subtyped as H1N1. In week 1, 19 jurisdictions with sufficient data reported minimal to moderate levels of activity, while 22 jurisdictions, including Pennsylvania and New York City, reported high activity. Additionally, 14 jurisdictions reported very high activity, including New York State and New Jersey. Activity levels are calculated from outpatient data reported to ILINet. For more information, please visit: https://www.cdc.gov/fluview/surveillance/2026-week-01.html.