Good news: This year’s flu vaccine appears to be particularly effective at preventing severe cases.

Bad news: Only about 40 percent of Americans eligible for flu shots have received one.

More good news: There’s still time to get protected before the virus peaks in Oklahoma, said Oklahoma Medical Research Foundation physician-scientist Hal Scofield, M.D.

According to the Centers for Disease Control and Prevention, influenza affects, on average, about eight percent of the U.S. population each year. The virus annually kills about 35,000 Americans and sends another 450,000 to the hospital.

Young children, people 65 years and older, and those with chronic medical conditions such as congestive heart failure, asthma, or diabetes are at greatest risk of severe disease.

“In the Southern Hemisphere, flu season runs about six months ahead of ours, which provides us with a window into the severity and most common strain as well as the effectiveness of the vaccine,” said Scofield, who also is associate chief of staff for research at the Oklahoma City VA Medical Center.

“This year, the vaccine appears to be a great match for the virus,” Scofield said. “Although complete data isn’t available yet, Australian health authorities reported that this year’s vaccine significantly reduced the risk of ending up in the doctor’s office from the flu.”

According to the CDC, pharmacies and doctor’s offices had administered about 51 million doses of adult vaccine as of November 25 – 13 percent below the same time last year. Similarly, the percentage of U.S. children who had received flu shots through early December was lower than at the same time for the past four years.

A survey conducted in August by the National Foundation for Infectious Diseases found 65 percent agreement among American adults that an annual flu shot is the best prevention, yet 43 percent didn’t plan to get one or were unsure if they would get one this year.

Among those in the latter group, 32 percent cited concern about side effects.

The most common flu vaccine side effects are soreness, redness or swelling at the injection site, and sometimes, low-grade fever. But, according to OMRF Executive Vice President & Chief Medical Officer Judith James, M.D., Ph.D., none of this is cause for alarm. “It’s your body developing protective immunity, and compared to contracting the flu, it’s nothing.”

James added that many fear getting a flu shot can cause the flu.

“The vaccine is made from proteins, not the virus,” said James, a member of the National Academy of Medicine and chair of OMRF’s Arthritis and Clinical Immunology Research Program. “It isn’t possible to get the flu from the vaccine.”

She noted that the flu vaccine typically reaches full effectiveness in two weeks.

As of the first week of December, Oklahoma flu activity is low, but increasing. According to the CDC, flu rates are high in neighboring states of Texas, New Mexico, and Colorado, and rising in Arkansas.

“Vaccination is your best defense, along with practicing smart health hygiene,” James said. “Stay home if you feel ill, wash your hands frequently and cover your nose and mouth when you sneeze or cough.”