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Flu Update: CDC Warns Cases of More Severe Strain of Influenza On the Rise

Feb 27, 2019 08:54AM ● By Editor

By Pam Wright of weather.com - February 27, 2019


As the flu continues to spread across the county, the Centers for Disease Control and Prevention warns that a new, more severe strain is on the rise.

The dominant strain of the flu at the beginning of the season was influenza A H1N1. In recent weeks, more than half of the reported new cases are for influenza A H3H2, a variant of swine flu, the CDC reported in its weekly U.S. Influenza Surveillance Report Friday. 

H3N2 is a non-human influenza virus that originates from pigs. When a swine flu virus infects humans, it is referred to as a variant, the CDC notes. 

"Influenza H1N1 viruses have been predominant overall this season, accounting for more than 70 percent of viruses analyzed this season, except for the southeastern part of the county where H3N2 viruses have predominated all season," CDC spokesperson Kristen Nordlund told weather.com "Last season was an H3N2 predominant season and it was one of the most severe seasons we have had in recent years." 

Influenza A H3N2 concerns the CDC because it seems to spread more easily from pigs to humans than other swine flu viruses. The agency also worries that it could change and begin spreading easily from people to people and notes that children born after 2001 have little to no immunity against the H3N2 virus. 

"We know that H3N2 can be more severe for older adults and very young children," Nordlund said. 

Overall, while cases of all strains of influenza involving hospitalizations and deaths is "well below what was observed last season," 41 children have already died so far this season.

This year's flu shot does not protect against H3N2, although researchers are working to make a vaccine. However, a flu shot is still recommended because it can make the symptoms milder. 

Nordlund noted that it's never too late to get a flu shot.

"As long as flu is spreading vaccination should continue," Nordlund said. "It’s important to know that it takes about two weeks for protection to set in."

Even people who have already had the flu this year might want to consider getting the vaccine since you can become infected by multiple strains of influenza in a single season.

People at high risk for flu complications include children younger than 5, adults 65 years and older and pregnant women, the CDC says. Those with medical conditions such as asthma, chronic lung or heart disease, diabetes and obesity are also at risk for flu complications, including pneumonia.

Anti-virals like Tamiflu are effective in lessening the symptoms of the flu but are most effective if administered within 48 hours of the onset of symptoms.

The CDC recommends that people with symptoms like fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches and fatigue seek medical attention as quickly as possible to avoid possible deadly complications.