The flu season in the United States started very early. It’s hitting the South and the West now

NEW YORK (AP) — The U.S. flu season has started early and is escalating quickly.

The Centers for Disease Control and Prevention released its latest update Friday, reporting that seven states reported high flu activity last week, compared to two states the week before.

The CDC also said that more than 3% of doctor visits last week were for flu-like illnesses, signaling that flu season is truly underway.

Louisiana is experiencing the worst so far.

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Flu season is “taking off and it’s heading in a direction that’s only expected to intensify in the next month or two,” said Dr. Fred Lopez, an infectious disease specialist at the LSU Health Sciences Center in New Orleans.

“If you haven’t been vaccinated, you should get vaccinated now,” he added.

Early-season flu activity is higher than typically seen at this point in the year, although it’s not clear whether that means this season will be worse than others, according to the CDC update.

But that’s not a good sign: The flu hospitalization rate in mid-October was the highest seen in an early fall in more than 15 years, noted Dr. Anna Durbin of Johns Hopkins University during a recent press briefing.

The CDC estimates that at least 2.6 million illnesses, 36,000 hospitalizations and 2,100 deaths so far this season are linked to flu infections.

The outbreak began in the South and West of the country, and states experiencing high flu activity so far include California, Louisiana, Oregon, South Carolina, Tennessee, Texas and Washington, according to the CDC.

It’s not uncommon for Louisiana to be among the first to see flu season increase each year. This is due at least in part to low vaccination rates, high poverty rates and the difficulties people face accessing health care, Lopez said.

Doctors expect an accelerated spread of the flu and other respiratory viruses as people travel and gather later this month for Thanksgiving.

“As we prepare to gather with family and friends during the upcoming holidays, it is especially important to get vaccinated,” Dr. Nicole Iovine, an infectious disease specialist affiliated with the University of Florida, said in an emailed statement this week.

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People should not get vaccinated if they are currently experiencing significant symptoms, as the body’s immune system is otherwise strained. But people should get a flu vaccine even if they’ve already had an infection this fall, because the vaccine protects against three types of flu viruses, and it’s not unusual for more than one strain to circulate each season, Lopez said.

Last winter’s flu season spiked in late December, and infections were particularly intense in some parts of the country. At the time, New York City health officials called it the busiest season in 20 years.

The season faded over the next few months and virtually ended by the end of March. But that spring, the CDC estimated there were at least 32 million illnesses, 380,000 hospitalizations and 24,000 deaths that season.

This fall, most of the illnesses so far are caused by a version of the H1N1 influenza A virus whose mutations have the potential to slip through the immune system’s defenses more easily. However, the data available so far suggests that the current vaccine “can recognize” the circulating virus and act against it, Andrew Pekosz, an immunology expert at Johns Hopkins University, said at a recent press briefing.

Health officials won’t know for months exactly how effective this year’s vaccine is. But “for now there is no reason to worry,” he said.

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