ALBANY — A late-season spike in flu infections in New York is prompting cautionary advisories from state health officials.
In weeks 15 through 18 of this flu season — April 10 through May 7 — 32,037 new infections were confirmed statewide.
The average for the same four weeks in the preceding 10 years was just 3,430 cases.
The seasonal influenza outbreak in New York typically starts slowly in autumn, peaks in late winter, then tapers off in spring.
In the current influenza season, reported cases peaked earlier than normal, in December, then bottomed out in January and February, then began to rebound in mid-March.
This bimodal pattern is unusual, the state Department of Health said Friday in an advisory to New York’s medical community, and it’s unknown whether influenza activity will remain elevated or for how long.
DOH said it would be extending its surveillance of influenza beyond its normal May 31 conclusion date, and continuing to provide updates as long as influenza activity remains elevated.
For the week ended May 7, a total of 7,945 new cases were reported in New York, 90% of which were the A(H3) virus that has been predominant this flu season in the state.
The A(H3) strain can cause illness in people of all ages but is known to be particularly infectious in young children and older adults, DOH said.
Of the 100,656 influenza cases confirmed by lab tests through May 7, 59% were in patients younger than 18. Of the 5,600-plus hospitalizations reported through that date, 42% involved patients age 65 or older.
The state Department of Health earlier this week told The Daily Gazette:
“This is unusual, but not unprecedented. The last time the flu season was extended was 2013. These trends are not limited to New York — the extension of the flu season and the continued elevated number of cases is a national trend.
“Flu seasons often vary in their severity, based on the flu viruses that are circulating, the effectiveness of that season’s vaccine, and the number of individuals vaccinated.”
Through May 14, the DOH reported, 108,958 cases had been reported in the 2021-2022 flu season. That’s the third-highest total in a 13-year database maintained by DOH going back to 2009-2010.
The highest was 2019-2020, which saw 157,758 confirmed cases, but it coincided with the arrival of the COVID pandemic, which may have altered influenza testing and infection patterns.
The second-highest case total was 128,247 in 2017-2018. During that flu season, only 5,008 cases were confirmed in weeks 15-18, compared with the 32,037 in the same four weeks this year.
State Health Commissioner Dr. Mary T. Bassett this week urged New Yorkers to protect themselves:
“It is easy to become complacent about the flu when our minds are on the latest COVID-19 wave and with the weather turning warmer,” she said in a news release. “But we know that influenza rates are climbing alongside COVID-19 cases, so we must be vigilant these next few weeks and take precautions to keep healthy. Wear a mask in indoor public spaces if living in high-risk counties or personally at-risk, and stay home if you feel ill.”
DOH said the flu vaccine remains effective late in the season and anyone age 6 months or older can receive it up to June 30.
The following list of area counties shows the season–to-date total of influenza cases for 2021-2022 and, in parentheses, the seasonal average from 2009-2010 to present:
ALBANY: 667 (708)
FULTON: 147 (169)
MONTGOMERY: 200 (208)
RENSSELAER: 367 (336)
SARATOGA: 1,215 (913)
SCHENECTADY: 396 (694)
SCHOHARIE: 81 (72)
NY STATE: 108,598 (60,998)
More from The Daily Gazette: