Did you know that you can have the flu without having flu symptoms? It’s particularly true for people over age 65—and it can be really dangerous.

To understand why, consider the H3N2 flu strain that’s been circulating this flu season. It is so fierce that it has overwhelmed many people, even many of those who were vaccinated against it. Hospitals are packed, hundreds of people have already died, and many more are at risk while the season continues into the spring. As always, people over 65 are more vulnerable than younger people to flu-related serious illness (such as pneumonia), hospitalization and death.

Here’s the shocker: A new study found that older people going to hospitals with respiratory illnesses—during flu season—were less likely than younger people to be tested for the flu! Here’s what the study found—and how to protect yourself…

UNDERCOVER OPERATION

Researchers analyzed how often flu tests were ordered for 1,422 patients who were admitted to four Tennessee hospitals during several of the past flu seasons. Many, but not all, had symptoms that can signal the flu, including cough or fever. The researchers looked at the rates of testing for the flu according to doctors’ orders. They also independently—and surreptitiously—tested each patient for the flu themselves.

Results: Doctors flu-tested only 28% of patients, and were only about half as likely to order flu testing for patients 65 or older than they were for patients who were younger.

Important finding: More than one-quarter of the older people with confirmed influenza infection in this study did not have classic influenza-like signs such as cough and fever. Here’s why: Older people often don’t develop the cardinal signs of infection from the flu—their immune systems do not respond as vigorously as younger people’s. For example, they’re less likely to develop a fever, which is one of nature’s defenses against many viruses and bacteria. Plus, older people may have lower normal temperatures, so the typical definition of fever (above 100.4°F) may not be the right guide.

As a result, in older people with the flu, it might initially seem like a worsening of symptoms of chronic conditions they already have, such as asthma, congestive heart failure or chronic obstructive pulmonary disease (COPD). Or they might just feel fatigued and under the weather. But doctors should know better—especially during flu season—because these patients are actually in grave danger.

WHY PROMPT DIAGNOSIS MATTERS

Knowing that you have the flu is critically important. Even though early symptoms of the flu may appear less worrisome in older people than in younger people, the flu can—and often does—ultimately come roaring forth in these older people and turn very serious very quickly. Research suggests that in people who are “high-risk”—and everyone age 65 or older is considered high-risk— early use of antiviral medications can significantly reduce the risk for serious complications of the flu, including bronchitis, pneumonia and death.

Important: The 15-minute rapid-flu test often used in doctors’ offices and hospitals frequently results in “false negatives,” meaning you may have the flu but the test doesn’t detect it. So if your rapid test is negative, ask your doctor to also give you a follow-up test, which can take a few hours.

If you’ve already had the flu shot and you feel ill during flu season, ask to be tested for the flu anyway. Especially this year, the vaccine is not a good match for the actual flu that is circulating, so it is quite possible to get the flu even though you’ve been vaccinated.

GET TESTED—BUT PROTECT YOURSELF FIRST

Because the flu results in such serious illness and risk for death this year, the Centers for Disease Control and Prevention (CDC) issued an emergency update that says that people at high risk who are suspected of having the flu should be started on antiviral medications immediately—even before an influenza test confirms the presence of the virus. It’s best to start antiviral medications within the first two days of having symptoms, and the earlier they’re started, the better they work. But the drugs may still be beneficial when treatment is started later. (Note: It’s still important to get accurate test results to find out if you do indeed have the flu, since that knowledge can guide your continued treatment.)

Bottom line: If you are over 65 and you don’t feel well, get tested for the flu even if you do not have a fever or cough. Don’t wait to see what happens or until you get much sicker—anti-influenza medication works best the sooner you start it and can help you avoid hospitalization. It’s possible that doctors and hospitals may be more attuned to flu testing this bad-flu year, but if it is not offered, ask to have the test.

More ways to protect yourself…

  • If you have not yet received a flu vaccination this season, get one. It’s not as effective this year as in many years, but it’s better than not getting it at all. And no, it’s not too late.
  • Ask your doctor about getting vaccinated against pneumococcal disease to protect you against pneumonia and other illnesses that can make the flu particularly deadly. The onetime-only vaccination series (usually two shots administered one year apart) is recommended for all people age 65 and older.

To learn more ways to prevent, survive and recover from the flu, see The Bottom Line Guide to Outliving the Flu.