The flu variant, which hits kids and the aged tougher than different strains, is presently dominant in america

A sign advertising flu shots is displayed at a Walgreens pharmacy in San Francisco, California January 22, 2018. A strong strain of H3N2 flu has killed 74 Californians under the age of 65 since flu season began last October.

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A variant of the flu that hits children and the elderly worse than other strains of the virus is currently dominant in the US, setting the country up for what could be a bad flu season.

Public health labs have detected influenza A (H3N2) in 76% of the more than 3,500 respiratory samples that tested positive for the flu and analyzed for the virus subtype, according to a surveillance report released Friday by the Centers for Disease Control and Prevention.

according to dr Jose Romero, director of the CDC’s National Center for Immunization and Respiratory Diseases, has historically linked the H3N2 variant to more severe flu seasons in children and the elderly.

“There are also early signs of influenza causing severe illness in these very two groups of people this season,” Romero told reporters on a call earlier this month.

The flu hospitalization rate has risen to a decade high this season. Overall, about 8 in 100,000 people are currently hospitalized with the flu, but seniors and the youngest children are hit much harder than other age groups, according to CDC data.

The hospitalization rate for seniors is 18 per 100,000, more than twice that of the general population. For children under the age of five, the hospitalization rate is about 13 per 100,000.

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At least 4.4 million people have contracted 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.

“Typically, when we have more H3N2, we have a more severe flu season — so longer duration, more children affected, more children with severe illness,” said Dr. Andi Shane, pediatrician and infectious disease specialist at Children’s Healthcare Atlanta.

The other influenza A variant, H1N1, is generally associated with less severe seasons compared to H3N2, Shane said. H1N1 accounts for about 22% of samples that test positive for flu and are analyzed for a subtype, according to the CDC.

The percentage of patients reporting flu-like symptoms, 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 the CDC.

Respiratory illness is also very high in Arkansas, Colorado, Georgia, Kentucky, New Jersey, Maryland, Mississippi, New Mexico, North Carolina and Texas, according to the CDC.

The CDC recommends that everyone 6 months and older get a flu shot. Children under the age of 8 receiving the vaccine for the first time should receive two doses for the best protection.

The flu vaccine is typically 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 when sick, cover coughs and sneezes, and wash hands frequently. Those wishing to take extra precautions may consider wearing a face mask in public.