Nurse Emily Brown, right, gives a flu shot to a Dignity Health Northridge staff member. All health care workers must be vaccinated every year.

There is no “good” flu season. But there can be very bad ones. And the 2017-18 flu season could be one of the worst ever in Los Angeles county, the state, the country and worldwide.

A particularly vicious influenza strain is not only making people ill, it is proving quite resistant to the vaccines initially developed to combat it.

Which is why health officials from the Valley, the Los Angeles County Department of Pubic Health, the state Department of Public Health (CDPH)  and the Centers for Disease Controls and Prevention (CDC) continue to urge the public to get flu shots if they have not yet received one, and have not become sick — along with frequent hand-washing or the wearing of a mask if you have a cough — in an effort to stem the further spreading of influenza virus.

“Two deadly strains are running back to back — one is the flu and the other is an upper respiratory standard cold/flu that is extremely severe,” said Dr. Diana Liv, a physician for Dignity Health Family Practice Medicine in Northridge.

“The upper respiratory one can go to pneumonia if you are predisposed. It’s not too late to vaccinate. And if you are sick, stay home; it’s extremely contagious.” 

At a press conference on Wednesday, Jan. 10, LA health officials confirmed 36 influenza-associated deaths in Los Angeles County. Last year at this time, 13 deaths associated with influenza had been reported. This flu season, emergency room visits for influenza-like illness symptoms are up 130 percent.

On Tuesday, Jan. 9, the state health department sent out a release saying flu activity in California”is widespread” and at levels usually seen at the peak of the influenza season.

According to the CDPH’s most recent report — for the week ending December 30 —  27 influenza-associated deaths in persons under 65 years of age were reported. Only influenza deaths in persons less than 65 years are reported to CDPH so the total number of deaths due to influenza is higher.

Last year, 68 had died from the flu by the end of February. But officials are concerned it this flu season could “outpace” that total.

“With the increase in influenza impacting many communities across the entire state, it is important to get a flu shot now if you have not done so already,” said Dr. Karen Smith, CDPH director and state public health officer.

In Los Angeles county, 33 people of all ages have died from the flu since October. 

Nationally, the CDC, in its latest influenza report dated Dec. 30, showed California as one of 46 states showing a “widespread activity” of influenza, and the proportion of outpatient visits for influenza has been at or above the national baseline average (2.2 percent) for six weeks so far this season.

The virus that has health officials most concerned is an influenza “A” strain known medically as H3N2. An influenza tracked in Australia this summer has produced the highest reported outbreak in that country’s history, with more than 200,000 cases reported by November.

What has been equally vexing for health officials has been the limited effectiveness of the initial vaccines.

There are typically four strains of flu — “A” strains and/or “B” strains — that manufacturers prepare vaccines for. The vaccines for this year were first decided upon in September 2016, and were made available seven months later.

But it turned out that H3N2 was much stronger and more resistant than anticipated for the vaccines first produced.

Dr. Pat Salber, a former emergency room physician who now runs a media company based in Marin, CA, just north of San Francisco, and a healthcare website known as The Doctor Weighs In,” told the San Fernando Valley Sun/El Sol that even in good years vaccines are primarily “40 percent to 60 percent” effective in combating influenza strains.

This year the effective rate against H3N2 have been 30 percent and below.

“It is why emergency rooms are filling up with people,” Salber said.

“All viruses don’t behave the same. And they mutate all the time,” she continued. “When vaccine manufacturers try to figure out the strains and vaccines, they do it by analyzing what goes around the world. And the early numbers of vaccine this year is not as effective this time as it has been in prior years, not as much protection for the strain that is dominant this year.”

But the fact is, Salber said, the flu shot “is still the best thing people can do” to protect themselves.

Those particularly at risk for developing flu-related complications include children younger than age 5 (and especially younger than age 2), adults 65 years and older, pregnant women, and residents in long-term health facilities.

It can take from 10 days to two weeks for the vaccine to work properly, so doctors are urging non-vaccinated people to act.

“Even if you get (the flu), it may be milder than if you had not gotten the shot at all. And you can still get the shot even though the flu season has started,” Salber said.

Individuals in high-risk groups that experience flu symptoms (i.e. fever, chills and feeling very tired accompanied by sore throat, muscle or body aches, headaches, or nasal congestion), should contact their health care provider early in the illness.

According to the CDPH, antiviral drugs can be prescribed by a physician and also work best if started within two days of getting sick. Individuals who are not in high risk groups and who have mild illness typically do not need medical care or antiviral drugs. These individuals should stay home and avoid contact with other people.

Anyone who experiences more severe symptoms —  such as trouble breathing, pain or pressure in the chest or abdomen, difficulty eating or drinking, or confusion — should contact their health care provider or seek emergency care. 

The flu season in the USA typically begins in October and peaks in March; it can also last until May.