As the 2018 flu season continues in the United States, one thing is becoming apparent: It’s a doozy. On February 9, health officials from the Centers for Disease Control and Prevention (CDC) reported that people with flu-like symptoms were seeking care at clinics and emergency departments at a level not seen since the 2009 flu. Widespread flu activity was seen in 48 states, with the sharpest increases in the eastern and southern states. At least 63 flu-related deaths in children had been reported, and influenza or pneumonia was causing nearly one out of ten adult deaths in the country.

 “This is a pretty bad flu season,” says Dr. Susan Donelan, Medical Director and Assistant Professor of Infectious Disease at Stony Brook University’s School of Medicine. “It’s one of the worst that I can recall in quite some time, both in how widespread it is and extent to which people are being hospitalized.”

Why is flu so severe this year?

Of the four seasonal flu strains circulating this year, the predominant one is H3N2, a subtype of an influenza A. About 8 out of 10 cases of flu occurring in the United States are caused by a strain of H3N2 (not to be confused with an H3N2 strain circulating in dogs or a different one found in pigs). H3N2 first emerged in Hong Kong in 1968, when it killed an estimated 1 million people worldwide.

No new genetic changes have been found that would make H3N2 more deadly this year – it’s just a nasty strain of influenza. The strain caused enough hospitalizations and deaths in Australia in July and August to earn the nickname “Aussie flu.”

How effective is the flu vaccine?

While this year’s flu vaccine protects well against three of the four influenza viruses circulating this year – another influenza A subtype, H1N1, and two Type B strains, Victoria and Yamagata – it doesn’t protect well against H3N2.

In Australia, the vaccine was only about 10% effective against the H3N2 subtype. However, that doesn’t mean that the flu will affect the United States in the same way, for several reasons. The same strain of H3N2 circulated last winter in the US, so more people are likely immune. And in Austraila, vaccination is only recommended for vulnerable populations – young children, older adults, pregnant women, and those with underlying diseases or weakened immune systems.

In the US, flu vaccine is recommended for almost everyone six months of age and older. However, only about 4 out of 10 adults, and 6 out of 10 children, receive the vaccine in any given year, according to CDC data.

Still, it’s too early to tell exactly how effective the vaccine will be in the US. “Vaccine effectiveness is something you calculate and assess after the season is over,” explains Donelan. “That’s when we can do a ‘lookback’ and estimate of the people who get ill, of those who got vaccinated, how many presented to a clinic, emergency department? How many ended up in the ICU or died?”

Other things also affect a person’s response to the flu vaccine. For instance, people with other health problems, especially weakened immune systems, may not have an ideal response to the vaccine; if they do get ill, it’s more likely that they will become seriously ill and perhaps die.

Most years, flu vaccine is about one-third effective, according to Donelan, who says she expects to see similar efficacy this year. “It’s never been as low in the U.S. as the 10% that was touted as the Australian experience,” she says. “It depends on how many people got the vaccine and who determined the viral subtypes that would be included in the vaccine. I don’t know how they do that in Australia as opposed to how we do that here.”

Who is Most at Risk?

For most healthy teens and adults, a bout of the flu is a miserable week or two of cough, fever, and body aches. But for very young children, older adults, pregnant women, and people with other conditions such as asthma, heart disease, or diabetes, the flu can be dangerous. Most people hospitalized with the flu this year are 65 years or older, with those in the 50-64 age group coming in a close second. Young children, of course, are at risk, because they may have little to no immunity. However, deaths have been reported this year in healthy adolescents and adults.

How Can I Protect Myself and My Family?

What can people do to reduce their risk? “I can’t help but emphasize that it is not too late to get a flu shot,” says Donelan.

While the flu shot may not offer complete protection against the flu, it may help to shorten the duration of illness and lessen symptoms. However, you’ll still be at full risk for about two weeks after you get the shot, while your immunity develops.

“Often people will tell me ‘I got the flu shot and then I got the flu,’” Donelan says. “But if you wait until the flu is prevalent, chances are that you’ll encounter the flu before you’ve developed a significant antibody response.”

Donelan says social distancing, which she describes as “kind of a viral version of sheltering in place,” is one effective method to slow the spread of flu. “When a school if closed because of the impact of flu in the community, it’s better not to congregate at the mall, gym, or other meeting places where people who may be incubating the flu are cross-pollinating,” she explains. “It’s a well-described methodology of trying to halt the spread of flu and other communicable diseases.”

What if I Get Sick?

If you are sick, you’ve got two goals: Get better, and don’t spread the disease.

“People who are sick shouldn’t go to work, to the mall, or other public places,” says Donelan. “We get flu from other people. People can shed the virus a day before they become ill. If you’re sick, follow cough and sneeze etiquette. Use a tissue, then throw it away. Remain hydrated; if you’ve been prescribed Tamiflu, take it.”

Most people can take care of themselves at home, but this is not the time for heroics. “If you start to feel better and then, two or three days later, you start feeling worse, absolutely contact your doctor or go to the emergency department. That’s a classic pattern for bacterial infection.”

If you live alone, call a friend, let them know you’re sick, and ask them to check on you regularly – via phone call or text, so they don’t get sick. Conversely, if you know someone who lives alone, you can do the checking in. “I always worry about people who live alone in general,” says Donelan.

If you do get sick:

• Ask your doctor about anti-viral medications such as Tamiflu. “Most studies suggest a benefit to initiation of Tamiflu in acute influenza,” says Donelan. Call your doctor if you start to feel the aches and pains of flu. Tamiflu works best if started immediately.
• Stay home: Don’t become a flu vector yourself. Stay home, especially if you work with young children, older people, or others who might be at greater risk of complications from the flu. You can go back to work 24 hours after your fever goes away without medication.
• Cover your cough. Every time you cough, you spray virus-laden droplets 3 to 6 feet away. Cough or sneeze into your elbow or shoulder, or use a tissue to cover your mouth and nose. Then throw away the tissue and wash your hands.
• Rest (but not on your back): Rest is essential – your body needs it to shore up the immune system and fight off the virus. But don’t rest horizontally. Sitting up allows better drainage from your lungs and will help you sleep better.
• Steam Away: Fill a bowl or the bathroom sink with hot water, and breathe in the steam. Or run a hot shower and sit in the bathroom. You can add a drop or two of menthol or eucalyptus oil if you’d like, although there’s no proof they really help with symptoms.
• Drink plenty of fluids and eat nutritious foods. Yes, you’re just lying in bed, but your body needs lots of fluid and energy to fight the invading virus. Eat and drink salty soups, tea, citrus, melon, and other foods high in nutrition and liquid content. Avoid caffeinated beverages such as coffee, tea, or colas, which can cause dehydration.
• Medicate: Discomfort can be lessened with acetaminophen (paracetamol – brand name Tylenol) or other over-the-counter anti-fever drugs, such as ibuprofen (Motrin) or naproxyn (Aleeve). Adults can take aspirin, but never give aspirin to children 16 and younger, as it may cause Reye’s syndrome. Avoid using cold and cough medications that contain antihistamines (which can dry up secretions) or cough suppressants, both of which can make it harder to clear phlegm from the lungs.

What about Kids?

Like most adults, most kids who develop the flu will recover on their own. But some children will need medical intervention, and caregivers need to watch for signs that things are not going well. “Very young children can’t verbalize what they’re feeling,” says Donelan. “Don’t feel badly about pestering your pediatrician. That’s what they do.”  

“Kids can change on a dime,” she explains. “You don’t have a child who says ‘Yesterday I felt better, but I feel lousy today.’ They like to look at books, then they don’t want to look at books; they like to watch TV, then they’re not interested in TV. If they’re not making wet diapers, drinking fluids, or if you can’t get their fever down, have the child evaluated. Parents know their kids, if something doesn’t seem right, trust yourself.”

• Children should be seen emergently if:
  • They are having difficulty breathing or breathing very quickly
  • Their skin turns bluish
  • They have a fever with a rash
  • They are so irritable that they don’t want to be held
  • They aren’t drinking enough fluid (measure by number of diapers in very young children)
  • Not waking up or responding to you

Additional Resources

For more tips on reducing the spread of flu, see the CDC’s Tip Sheet https://www.cdc.gov/flu/pdf/freeresources/general/everyday-preventive-actions-8.5×11.pdf