The United States is at the peak of one of the more active flu seasons in recent years, U.S. Centers for Disease Control and Prevention officials announced Friday.
Dan Jernigan, the director of the Influenza Division of the National Center for Immunization and Respiratory Diseases, said the season is "very active," and there are early indicators it may be severe. In the 13 years his office has tracked flu maps, this year is the first the entire continental United States has experienced a widespread flu outbreak.
"Flu is everywhere in the U.S. right now," Jernigan said.
He said the season started early and is "probably peaking right about now," causing a rapid increase in flu-related doctor visits and hospitalizations.
Jernigan and CDC Director Brenda Fitzgerald attribute the high flu activity to the prevalence of the H3N2 flu, this year's most common form of flu. H3N2 is associated with more severe illness, especially among children and the elderly. Flu seasons during which H3 viruses are prevalent are usually worse and come with more hospitalizations and deaths.
In the last week, doctors have seen an uptick in flu-related doctors visits while the rate of flu hospitalizations nearly doubled. The most recent hospitalization rate for flu was 22.7 per 100,000 people, up from 13.7 per 100,000 last week.
The strain is taking its worst toll on the elderly, but is also causing complications for Baby Boomers and young children. Those older than age 65 are experiencing the highest hospitalization rates, but those age 50 to 64 also have seen high numbers. In the last week, hospitalizations of children under five have almost doubled and there were seven more pediatric deaths, bringing the season total to 20.
Jernigan projected this year will be worse than the 2012-13 flu season, during which H3N2 was prevalent and there were about 56,000 estimated deaths. But the severity of this flu season isn't expected to be quite as bad as the 2014-15 season, during which vaccine effectiveness was very low and there were about 700,000 hospitalizations.
Since 2010, the CDC estimates there have been between 9.2 and 60.8 million flu cases each year. Annual hospitalizations range from 140,000 to 710,000 and deaths are estimated between 12,000 and 56,000 each year.
Even though we're at the peak, we likely have 11 to 13 more weeks left in the flu season.
"Even if we have hit the top of the curve or the peak of the seasonal activity, it still means we have a lot more flu to go," he said.
The best way to prevent the flu is to get the vaccine, said Fitzgerald, the CDC director. She said there's still time.
But, the vaccines are "far from perfect," Fitzgerald said. Jernigan said the effectiveness rate of this year's vaccines against the predominant H3 virus will be about 30%.
"We are very well aware that we need to have better flu vaccines," Jernigan said.
Aside from the vaccine, the CDC recommends people take their own steps to avoid the flu. This includes avoiding people who are sick, staying home when sick, cover your cough and frequently wash your hands.