The amount of influenza-like illness doctors are seeing is now high in most states, including Pennsylvania and New Jersey, and it’s still increasing, the U.S. Centers for Disease Control and Prevention said in its weekly report on the viral disease.
A separate measure of whether flu has broad or more isolated geographic reach within states found that all but a handful of states are experiencing widespread illness.
The level of influenza-like illness has been elevated for two months. The percentage of respiratory cases testing positive for flu is similar to what has been seen at the peak of recent seasons. A map of reported visits for flu-like symptoms shows a season that started relatively early and gathered strength quickly.
The hospitalization rate so far is similar to that of previous seasons, the CDC said.
While seasons often start with influenza A viruses dominating, the influenza B/Victoria strain is causing the most illness so far this season. Typically, influenza A leads to more serious symptoms. Protection from B/Victoria was included in this year’s flu shot. The A(H1N1), which is also in the shot, is the second most common strain now.
The CDC estimated that the flu has sickened more than six million people so far this year, and has led to 55,000 hospitalizations and 2,900 deaths. Five new pediatric deaths were reported in the week ending Dec. 28. Pennsylvania has reported nine flu deaths. New Jersey, which does not report flu deaths among adults, has had one pediatric flu fatality.
Most of the strains of the virus now circulating respond to antiviral medications for flu. Flu vaccines, considered the best way to avoid flu or at least keep it less severe, are still available. But it takes two weeks after the shot is given for antibodies to fully develop.
In Pennsylvania, the Health Department said that B/Victoria is dominating in some regions of the state while A(H1N1) is more common in others. Influenza B is the predominant strain in New Jersey.