This year’s flu season is shaping up to be a severe one, with increasing reports of emergency department and outpatient visits for influenza-like illness, and hospital admissions for all causes of pneumonia.
Last week, the Centers for Disease Control and Prevention (CDC) announced interim studies that showed the 2014-2015 flu vaccine to be only 23 percent effective in preventing influenza illness requiring medical attention. Most influenza strains identified so far this season have been H3N2 subtype influenza A viruses, and the difficulty preventing the flu likely reflects the predominance in the United States of a different H3N2 subtype than the one included in the vaccine.
“There’s still a benefit to getting the vaccine,” said Albert Shaw, MD, PhD, a Yale Medical Group infectious-disease specialist. Flu vaccines are prepared months before doctors know which strains of flu will be most prevalent; this year’s vaccine still protects against other strains that could circulate at higher levels later in the season (such as influenza B), and may provide some degree of protection from H3N2. “There is evidence that even a poor match can potentially diminish the severity of symptoms,” Dr. Shaw said.
Even if the vaccine were only 10 percent effective, he added, studies suggest “we’re still talking about saving thousands of hospital admissions, particularly in adults over age 65, in a fairly active influenza season.”
Especially for vulnerable groups, flu can be a true menace that can lead to hospitalization and death, often from pneumonia. These groups include people older than 65 or younger than 2, as well as those with underlying health problems, especially chronic lung disease (including asthma and COPD), diabetes, chronic heart, kidney or liver disease, or obesity. Other at-risk groups include pregnant and postpartum women, Native Americans, residents of long-term care facilities and nursing homes, those receiving immunosuppressive medications or chemotherapy, and those with immunodeficiency syndromes such as HIV infection.
If you have symptoms, call right away
Everyone should be familiar with flu symptoms, which include body aches, cough, sore throat, runny nose, headache, fatigue, and (in most people) fever. People in vulnerable groups experiencing flu-like symptoms should be given antiviral medications quickly. Oseltamivir (Tamiflu®) is the most widely prescribed antiviral medication; the other two are zanamivir (Relenza®) and peramivir (Rapivab®).
These drugs could make a life-or-death difference, especially when they are started in the first 48 hours of illness. High-risk or hospitalized patients shouldn’t wait for test results to confirm the flu before receiving antivirals.
Lower-risk people can benefit, too. A course of antivirals may shorten the illness by a day or more, said Shaw, who recommends calling a provider as soon as flu-like symptoms begin. “It’s certainly worth it for most people,” he says.
Apart from antivirals, old-fashioned advice for flu patients still applies: rest, time, over-the-counter treatments for fever and cough, and plenty of fluids to replace the loss of fluids from the lungs and skin through fever.
Flu can quickly take a turn for the worse. Anyone with flu-like symptoms should seek emergency care if they experience chest pain or pressure, trouble breathing, lightheadedness or confusion, trouble taking in enough fluids, severe vomiting, or symptoms that improve and then return with fever and cough. Children should see a provider right away if they develop trouble breathing or eating; become bluish, irritable, or dehydrated (for example, crying without tears or wetting fewer diapers); break into a rash with fever; or get better, and then worse again with fever and cough.
If you’re in high-risk group, Shaw stressed, “you have to have a lower threshold for contacting your physician.”
For detailed information on flu prevention, treatment, and caregiving, visit http://www.cdc.gov/flu/index.htm.