Hawaii appears to be seeing the worst flu season in years with patients inundating medical clinics and emergency rooms across Oahu.

“This is the biggest Hawaii flu season in at least five years,” said Dr. Robert Ruggieri, owner of Island Urgent Care, which ran out of the flu vaccine Tuesday. “The vaccine (health officials are) estimating was about 10 percent effective this year because another major strain came through they weren’t expecting. There’s no question this is a bad strain. There are deaths all over the nation.”

State Department of Health officials did not say whether the strains being seen locally are covered by the vaccine, but are urging people 6 months and older to get the flu shot.

Australian health officials estimate the vaccine is 10 percent effective against a flu strain known as the H3N2 virus, according to the Centers for Disease Control and Prevention.

There has been a dramatic spike in flu cases over the last few weeks. Of the 976 deaths in Hawaii since flu season began in October, 134 were due to pneumonia and influenza, state Health Department statistics show.

“All these people are filling up the ERs. It’s totally out of hand,” said Dr. James Ireland, assistant clinical professor of medicine at the University of Hawaii John A. Burns School of Medicine. “In the last three weeks I’ve seen more flu than I have in the last year. Every other day I’m putting somebody in the hospital with the flu. There’s no doubt, it’s bad.”

Protecting against influenza is especially important for young children, pregnant women, seniors and those with high-risk conditions such as asthma, diabetes, heart and lung disease or a compromised immune system, the Health Department said.

“The flu can make chronic health problems even worse and trigger asthma attacks by causing further inflammation of the lungs and airways, while those with chronic congestive heart failure may experience a worsening of their condition,” state Epidemiologist Sarah Park said in a news release.

Besides the flu shot, DOH recommends frequently washing your hands, covering your mouth when coughing or sneezing and staying home when you’re sick.

The surge in flu cases comes after the DOH ended its “Stop Flu at School” vaccination program for dozens of Hawaii’s public schools this year due to reduced federal funding and other considerations. Since 2007 nearly 600,000 flu shots have been administered at more than 300 public, private and charter schools statewide. Over the past year vaccinations were administered at 167 schools.

Flu and pneumonia were the nation’s eighth leading cause of death in 2016. An estimated 25 million influenza cases were reported that year, resulting in 11 million medical visits, 310,000 hospitalizations and 12,000 deaths, CDC data shows.

“We’re definitely very busy. It seems like in the last two weeks we’ve gone from very little flu activity to several cases a day admitted through the ER,” said Dr. Rick Bruno, vice president of patient care at The Queen’s Medical Center. “Time will tell how big of a flu season this is going to be.”