A sign advertising flu shots is displayed at a Walgreens pharmacy in San Francisco, California, on January 22, 2018. A strong strain of the H3N2 flu has claimed the lives of 74 Californians under the age of 65 since flu season began last October.
Justin Sullivan | Getty Images
A variant of the flu that affects children and seniors worse than other strains of the virus is currently prevalent in the US, preparing the country for a potentially bad flu season.
Public health labs have detected influenza A (H3N2) in 76% of more than 3,500 respiratory samples that tested positive for flu and analyzed for virus subtype, according to a surveillance report released Friday by the Centers for Disease Control and Prevention.
The H3N2 variant has historically been associated with more severe flu seasons for children and the elderly, according to Dr. Jose Romero, director of the CDC’s National Center for Immunization and Respiratory Disease.
“There are also early signs of flu causing serious illness this season in exactly these two groups of individuals,” Romero told reporters during a phone call earlier this month.
Flu hospitalizations have risen to a decade high this season. Overall, about 8 people per 100,000 are currently hospitalized with the flu, but seniors and the youngest children are much harder hit than other age groups, according to CDC data.
The hospitalization rate for seniors is more than double that of the general population at 18 per 100,000. For children under the age of five, the number of hospital admissions is about 13 per 100,000.
At least 4.4 million people have been sickened by the flu, 38,000 have been hospitalized and 2,100 have died since the start of the season. Seven children have died from the flu so far this season.
“If we have more H3N2, we tend to have a more severe flu season — so longer duration, more kids affected, more kids with serious illness,” says Dr. Andi Shane, a pediatrician and infectious disease expert at Children’s Healthcare Atlanta.
The other variant of influenza A, H1N1, is generally associated with less severe seasons compared to H3N2, Shane said. H1N1 makes up about 22% of samples that tested positive for flu and analyzed for a subtype, according to CDC.
The percentage of patients reporting symptoms similar to the flu, a fever of 100 degrees or more plus a sore throat or cough, is currently highest in Virginia, Tennessee, South Carolina, Alabama and Washington DC, according to CDC.
Respiratory disease is also very high in Arkansas, Colorado, Georgia, Kentucky, New Jersey, Maryland, Mississippi, New Mexico, North Carolina and Texas, according to CDC.
The CDC recommends that everyone 6 months or older get a flu shot. Children under 8 years of age receiving the vaccine for the first time should receive two doses for the best protection.
The flu vaccine is normally 40% to 60% effective at preventing illness, but people who do get sick are less likely to end up in the hospital or die, according to the CDC.
Public health officials are also encouraging people to stay home if they are sick, cover coughs and sneezes, and wash their hands regularly. Those who want to take extra precautions can consider wearing a face mask indoors in public.