Maine caught up with the rest of the nation this week, reporting “widespread” flu activity in all 16 counties, according to the U.S. Centers for Disease Control and Prevention.

Virtually the entire country is now reporting widespread flu, the first time that’s happened in 13 years. The flu season, which runs from October to May, started early and has so far been severe, according to the federal CDC.

But until Friday, Maine, New Hampshire, New Jersey and Hawaii had been spared the “widespread” designation because those states had relatively fewer cases than other parts of the country. Hawaii was the only state not experiencing widespread flu activity as of Friday.

“I suppose it took a little longer to inch its way up here,” said Dr. Siiri Bennett, an epidemiologist with the Maine Center for Disease Control and Prevention. Bennett said Maine’s population is more sparse, which may help prevent flu from spreading. But it also has an older population, so those who contract influenza are more at risk.

Through Jan. 6, Maine had reported 768 cases of people who had tested positive for flu, almost all for H3N2, a virulent strain of influenza A more likely to result in hospitalization. During the same time period, 211 flu cases in Maine required hospitalization, about 27 percent.

While Maine reported 5,830 flu cases in 2016-17, the strains circulating were less severe and only 14 percent required hospitalization, according to the CDC. Older people with the flu are more likely to be hospitalized – the mean age of flu cases requiring hospitalization last year in Maine was 68.

Caroline Cornish, a Maine Medical Center spokeswoman, said the hospital has seen an increased number of flu cases in the emergency department this year, but not an unusual amount.

“It’s January, so we’re getting flu cases,” Cornish said.

There have been 13 deaths at least partly attributable to influenza in Maine through Jan. 11, according to the Maine CDC. For the entire 2016-17 flu season, Maine had 71 flu-related deaths. Nationally, there are typically more than 2,000 flu-related deaths each week during flu season, according to the federal CDC.

Influenza is a contagious respiratory illness that usually comes on suddenly, according to the CDC. Symptoms can include fever, cough, sore throat, stuffy nose, muscle or body aches, headaches and fatigue. Symptoms can also include vomiting and diarrhea, though this is more common in children than adults. Complications, which may be serious, can include pneumonia, bronchitis, and ear and sinus infections.

Health experts say people can still protect themselves by getting flu shots, usually available at little or no cost at primary care practices, local drugstores or workplaces.

Because scientists have to predict months in advance what strains of flu will be circulating, the flu shot doesn’t protect against all strains. However, those who get a shot and still contract the flu experience milder and shorter symptoms, research suggests.

The vaccine was 48 percent effective in 2016-17 and 59 percent effective in 2015-16, according to the federal CDC. It’s not yet known how effective the vaccine is for this season.

During flu season, people should be particularly vigilant about practicing good hygiene, including frequent hand washing, avoiding contact with sick people and covering the mouth when coughing.

The actual number of flu cases is far higher than the number of reported cases, because most people recover at home and are never tested. The federal CDC estimates that there are 9.2 million to 35.2 million cases of the flu each season nationally, with hospitalizations ranging from 140,000 to 710,000.

Bennett, the Maine CDC epidemiologist, said that older populations are more at risk, especially those in long-term care facilities, such as nursing homes or assisted living centers. There have been 24 outbreaks – defined as three or more people falling ill from the flu – in long-term care facilities this season.

“We’re hoping this is the peak, but we really can’t say,” said Bennett, noting that the flu is notoriously unpredictable. “We don’t have a crystal ball.”

Last year, for instance, there were 467 cases in Maine through the end of January, but 5,830 cases by the end of the season. However, about 40 percent of the cases were for influenza B, a less virulent strain.

Dr. Dan Jernigan, who heads up the federal CDC’s influenza division, told STAT news that this flu season is expected to be severe.

“There’s lots of flu in lots of places,” he said.

Staff Writer Joe Lawlor can be contacted at 791-6376 or at:

jlawlor@pressherald.com

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