Doctors’ phones are ringing and the emergency rooms are full of people coughing, wheezing and feverish. It’s the worst year for the flu in about 15 years.

“Our flu volume since December is up six-fold,” said Dr. Umair Baig, an emergency physician at Greater Baltimore Medical Center in Towson. “It’s way higher than it’s been in the decade-plus I’ve been here.”

The U.S. Centers for Disease Control and Prevention reported it’s the worst season since 2010-2011, and Baig said the crush in Maryland is leading to extra-long wait times in the emergency departments, which already had some of the longest waits in the country.

It’s disproportionately due to flu, he said, though he’s seeing patients with other viruses including COVID-19. Some are coming in with secondary infections related to those conditions, such as pneumonia.

The number of people hospitalized in Maryland from the flu peaked at the end of January with 666 people, state health data shows. But doctors say they’ve seen little relief this month in terms of the overall caseload. And there are still months to go in the season. Baig and other doctors noted it’s possible to get reinfected with a different strain of flu.

The state has reported 3,156 hospitalizations since late September due to the flu. Seven people — six adults and one child — infected with the flu have died.

Nationally, the picture is similar. An estimated 24 million people have been sickened from the flu. Roughly 310,000 have been hospitalized and 13,000 died, including 57 children.

“I’m seeing a lot of patients before they go to the emergency department and a lot after they get admitted,” said Dr. Wendie Grader-Beck, who specializes in internal medicine and pediatrics at the University of Maryland St. Joseph Medical Center in Towson. “What they have in common is they are not vaccinated.”

Data show fewer than 1 in 3 people have gotten a flu shot this season in the state, reflecting a lower vaccination rate across the country since the coronavirus pandemic.

The result is more people getting sick and a greater number of those suffering with complications related to the flu, experts say. Vaccines can prevent infection and lessen the effects when people do get sick, Grader-Beck said. People with underlying health conditions such as asthma or COPD can be especially vulnerable.

Even those who don’t feel they’re at risk for severe complications can still spend a miserable week in bed, especially if they haven’t been vaccinated, experts say.

Grader-Beck said she is still working to counter misinformation about the safety and effectiveness of vaccines. For most people, the benefits far outweigh the risks, preventing disease or significantly lessening the worst symptoms.

Vaccines are still widely available and can still be used to help prevent illness this season. Antiviral medications can be prescribed early in an infection to prevent severe illness. For some, Grader-Beck said, it’s also appropriate to take the medication to prevent infections for those who have been exposed to the flu.

There are several options available to those battling the flu.

Grader-Beck said there are home flu-COVID tests available to help confirm diagnoses. Those suffering symptoms can also make a telehealth appointment with their doctor during which they can learn whether they need a prescription, or even should go to the hospital. That kind of inpatient care, she said, is usually for those having trouble breathing, an irregular heart beat or shows sign of a secondary infection.

Those with active symptoms who need to leave the house should wear a surgical mask to prevent the spread of the flu, she added. Experts encourage everyone to wash their hands or use alcohol rub frequently.

Dr. Scott Burger, chief medical officer at University of Maryland Urgent Care, said a visit to a facility like his can often address a patient’s condition while preventing them from contributing to a bottleneck at a local emergency room.

State health officials have also launched an awareness campaign about the importance of inoculations. The $1.8 million, CDC-funded awareness campaign launched in December encourages people to get vaccinated against flu, COVID-19 and RSV.

The CDC recommends anyone 6 months or older get their flu and COVID vaccines, and pregnant women, infants, seniors and those with serious underlying medical conditions get inoculated for respiratory syncytial virus. The virus also known as RSV is highly contagious and especially dangerous to babies.

Pregnant people can get the RSV vaccine to protect their newborns between 32 and 36 weeks, and there is also a vaccine available for babies whose mothers were not vaccinated.

“RSV poses a significant threat to the health of our most vulnerable residents, including newborns and older adults, but there are safe and effective vaccines to protect ourselves and those we love,” said Dr. Nilesh Kalyanaraman, deputy secretary for public health services, in a statement.