As predicted by experts earlier this fall, the 2022-2023 flu season is shaping up to be one for the record books. According to the Centers for Disease Control and Prevention (CDC), Alabama, Georgia, Mississippi, North Carolina, Tennessee, South Carolina, Virginia, and Washington DC are categorized in purple as “very high” for flu activity about one month ahead of schedule. Five more states (Arkansas, Kentucky, Louisiana, New Jersey, and New Mexico) are close behind in the maroon “very high” category.

According to the CDC’s Flu View, as of November 5, nearly 14,000 positive flu tests have been reported, more than 12 times the number reported at the same time in 2019. Additionally, there have been an estimated 1,300 deaths from the flu, including at least three children.

Check this CDC map to see if you live in a ‘high risk’ flu state

This flu transmission is happening earlier than usual, as the winter flu season typically heats up in December and January. Hospitalizations for flu at this rate and month in flu season haven’t been this high since the 2009 swine flu pandemic, according to the CDC.

[Related: No, you can’t get the flu from a flu shot.]

Predicting the severity of the flu season can be a real guessing game, as the virus is constantly mutating. “We’ve been saying for the last few years to expect bad flu seasons, and that didn’t pan out,” said Andrew Handel, a pediatric infectious disease specialist at Stony Brook University, in an interview with PopSci last month. “I think the public gets very frustrated with our predictions about flu seasons, but it’s all a prediction based on the best information we have available.”

However, for this flu season, there are a few critical indicators that we are in for a tough winter. The United States looks to Australia for a glimpse of what to expect, since flu season typically kicks off in the southern hemisphere. According to data from Australia’s Department of Health and Aged Care, the country just faced one of the worst flu seasons in five years. One of the positives outcomes from analyzing this flu data is that scientists can see which strains of the virus are circulating the most, and that knowledge can create more effective annual flu vaccines. Jennifer Lighter, a pediatric infectious disease doctor at NYU Langone Health, told PopSci last month that scientists don’t really have the estimates of how effective this year’s vaccine is until after cases emerge, but “we know that the current vaccine is matching well with what’s circulating in communities in the southern hemisphere.”

[Related: Is it flu or RSV? It can be tough to tell.]

However, vaccination rates for the flu remain pretty low. Only 57 percent of eligible children were immunized against influenza during the 2021-2022 flu season— a 5.6 percent drop from the pre-pandemic 2019-2020 season, according to the CDC. For adults, the number was even lower, with a range of 35.9 to 60 percent vaccinated during the 2021-2022 season. This in addition to waning immunity since most people’s immune systems haven’t been exposed to the flu for about three years, due to social distancing mask requirements due to the COVID-19 pandemic making the flu virtually disappear, points to a rough flu season.

There are many ways to protect yourself against the flu, with the first being getting vaccinated. “The flu shot is analogous to the COVID shot. There may be breakthroughs but they’re both preventing severe disease and keeping you out of the hospital,” Lighter said. “And that’s really the main purpose of a vaccine—to keep you from getting significantly sick.”

The CDC also recommends staying home when sick, covering your mouth and nose when you sneeze, frequent hand washing, and general health habits (getting enough sleep, healthy food, and exercise).