Health officials report that the U.S. influenza season has begun. At least seven states have reported high levels of illness, and other areas of the country are seeing an increase in cases.
The Centers for Disease Control and Prevention published new influenza data on Friday. It showed very high activity in Louisiana last week, and high activity also in Alabama, Florida Georgia, Mississippi, New Mexico, and South Carolina. The flu activity was high in Puerto Rico and the District of Columbia, where officials declared an epidemic of influenza earlier this month.
“We’re going to the races,” Dr. William Schaffner said, an infectious disease expert at Vanderbilt University.
The winter flu season usually begins in December or early January. It started in October of last year and will be arriving in November this year.
The flu activity in New York City was mild but increasing. While flu activity in Alaska has been high for several weeks, Alaska did not provide data last week.
The tracking of flu during flu season is based in part on the reports from people who have flu-like symptoms and visit doctors’ offices or hospitals. Many people are not tested for flu, so their infection cannot be confirmed by lab. COVID-19, as well as other respiratory viruses, can sometimes cloud the picture.
Alicia Budd who heads the CDC’s influenza surveillance team said that several indicators show “continued increase” in flu.
The flu virus that has been causing the most hospitalizations this year is not the one that causes the greatest amount of deaths and hospitalizations among the elderly.
The CDC estimates that at least 780,000 people have been infected with flu this fall. At least 8,000 of them were hospitalized, and there are at least 490 deaths related to flu, including at least one infant.
Budd stated that the effectiveness of the current influenza vaccines is not known, but that the shots are well matched to the strains of flu that are currently showing up. CDC data shows that in the U.S. about 35% adults and 33% children have received a flu vaccine. This is down from last year for both categories.
The flu vaccination rate is higher than the rates of COVID-19 or RSV. Around 14% of adults, 5% of children and 13.5% of older adults have received the COVID-19 vaccine.