The flu, or influenza, is a respiratory illness caused by a virus that typically presents with symptoms like fever, body aches, cough, and fatigue. While most people improve within about a week, symptoms can seem to get better and then return, a phenomenon often called a flu relapse. This can be concerning.
Understanding Flu Relapse
One common reason for returning flu symptoms is a secondary bacterial infection. The influenza virus can weaken the immune system, making the body more susceptible to other pathogens. This vulnerability can lead to bacterial infections like pneumonia, bronchitis, or sinus and ear infections, which often manifest with new or worsening symptoms after the initial viral illness has improved. These secondary infections are a significant cause of complications.
Another possibility for returning symptoms is persistent viral activity or incomplete recovery from the initial flu infection. If the immune system has not fully cleared the virus, or if a person resumes strenuous activities too soon, the body may not have adequate time to recover, causing symptoms to re-emerge. While less common, reinfection with a different strain of the influenza virus is also possible, as these viruses constantly mutate, and immunity to one strain does not guarantee protection against another.
Recognizing the Signs of a Relapse
Distinguishing a true flu relapse from lingering post-flu symptoms or other illnesses is important. A relapse typically involves a return of significant, acute flu-like symptoms after a period of feeling better, often a few days to a week of improvement. Look for symptoms that are worse than the initial flu or are entirely new, rather than just a prolonged cough or fatigue, which can linger for weeks after the initial infection.
Specific indicators that may suggest a relapse include a high fever returning after it subsided, a severe cough that produces colored phlegm, or the onset of shortness of breath. Intense fatigue and severe body aches reappearing are also signs to monitor. These worsening or new symptoms, especially after a period of improvement, suggest a new challenge.
When to Seek Medical Care for Flu Relapse
There are specific warning signs that indicate the need for prompt medical attention during a flu relapse. Seek immediate care if you experience:
- Difficulty breathing
- Shortness of breath
- Persistent pain or pressure in the chest or abdomen
- Sudden dizziness
- Confusion
- Inability to stay awake or arouse
- Severe or persistent vomiting
- Seizures
A fever that returns after being gone for several days, especially if high, or a worsening of chronic medical conditions also signals the need for professional medical advice. Certain individuals are at higher risk for complications and should be particularly cautious, including infants, young children, pregnant women, adults aged 65 and older, and people with underlying health conditions like asthma, diabetes, or heart disease. If there is any uncertainty about the severity of symptoms or if they are concerning, consulting a healthcare provider is always recommended.
Managing Symptoms During a Flu Relapse
While awaiting or after seeking medical advice, several self-care strategies can help manage symptoms during a flu relapse. Adequate rest is important, as it allows the immune system to conserve energy and fight infection. Returning to normal activities too quickly can prolong recovery.
Staying well-hydrated is important to prevent dehydration. Drinking plenty of fluids like water, clear broths, and electrolyte solutions helps replace fluids lost through fever. Over-the-counter medications such as acetaminophen or ibuprofen can help reduce fever and alleviate body aches and headaches.
It is important to avoid aspirin for children and teenagers due to the risk of Reye’s syndrome. Practicing good hygiene, such as frequent hand washing and covering coughs, helps prevent further spread. If antibiotics are prescribed for a secondary bacterial infection, complete the full course as directed by a healthcare professional.