5 Illnesses that cause flu-like symptoms: Identifying, treating, and when to seek help

Flu-like symptoms, which include fever, chills, body aches, fatigue, and headache, can arise from various illnesses beyond the flu itself. Recognising these symptoms is vital for appropriate treatment and understanding when professional healthcare is necessary. In this guide, we’ll examine flu symptoms, five illnesses that mimic flu symptoms, tips for distinguishing between conditions, available treatments, and when to seek medical help.

What are common symptoms of the flu?

The flu, or influenza, is a viral respiratory infection that typically causes:

• High fever
• Chills and sweats
• Muscle or body aches
• Fatigue or weakness
• Headache
• Sore throat, cough, and congestion

While these symptoms are flu indicators, they can overlap with other illnesses. Identifying their unique qualities can help differentiate the flu from other possible conditions.

Illnesses that can cause flu-like symptoms

Certain illnesses have similar symptoms to the flu, making diagnosis challenging without testing. Here are five common conditions that may cause flu-like symptoms:

COVID-19:

COVID-19, caused by the SARS-CoV-2 virus, shares symptoms with the flu, such as fever, chills, body aches, and fatigue. However, COVID-19 often includes unique symptoms like loss of taste or smell, which rarely occur with the flu. COVID can also cause prolonged symptoms (known as “long COVID”) that persist even after recovery from the acute phase.

Mononucleosis (Mono):

Also called “the kissing disease,” or Glandular Fever, mono is caused by the Epstein-Barr virus. It produces flu-like symptoms, including fatigue, sore throat, and swollen lymph nodes, but fever in mono is often less intense and can last longer. Mono typically also causes extreme fatigue that may persist for weeks or even months.

Strep throat:

Strep throat, a bacterial infection, can cause fever, sore throat, and swollen lymph nodes. While body aches are less common, people with strep throat often experience throat pain, difficulty swallowing, and white patches in the throat. Unlike viral illnesses, strep requires antibiotics for effective treatment.

Pneumonia:

Pneumonia, an infection of the lungs, can present flu-like symptoms, including fever, chills, fatigue, and body aches. Unlike the flu, pneumonia may also cause shortness of breath, chest pain, and a persistent, sometimes productive cough.

How can you tell if you have the flu, COVID, or another illness?

Flu, COVID-19, and other infections share common symptoms, making it difficult to differentiate them without medical testing. Here are a few distinctions:

• Symptom duration: The flu generally lasts 1-2 weeks, while COVID-19 symptoms may extend or recur due to long COVID.
• Unique symptoms: Loss of taste or smell is more characteristic of COVID-19, while a sore throat with visible white patches is typical of strep throat.
• Physical signs: Conditions like the flu may present with a runny nose and cough, whereas mono often leads to prolonged fatigue and swollen lymph nodes.

Testing is often necessary to confirm the cause, as these overlapping symptoms can make at-home diagnosis challenging.

How are flu-like symptoms treated?

Treating flu-like symptoms depends on the underlying cause, but general supportive care includes:

• Rest and hydration: Adequate rest and fluid intake support immune function and recovery.
• Over-the-counter medications: Medications like paracetamol or ibuprofen can reduce fever and body aches. Decongestants or cough suppressants may relieve other symptoms.
• Antivirals or antibiotics: Prescription antivirals are available for the flu, while antibiotics treat bacterial infections like strep throat.
• Hydration and nutrition: Proper hydration is vital, especially for illnesses with fever, to prevent dehydration.

When a specific diagnosis is confirmed, your healthcare provider will provide targeted treatment. Adhering to their guidance can help prevent complications and improve recovery times.

Can flu-like symptoms be prevented?

There are preventive measures to reduce the risk of contracting flu-like illnesses:

• Vaccination: Annual flu shots and COVID-19 vaccinations significantly reduce the risk of severe illness.
• Hygiene practices: Frequent handwashing, using sanitiser, and avoiding touching your face can prevent the spread of germs.
• Avoiding sick contacts: Avoid close contact with those who are ill, especially during flu season.
• Healthy lifestyle: Maintaining a balanced diet, getting regular exercise, and managing stress support a strong immune system.

What tests can diagnose flu-like illnesses?

Several tests are available to confirm the cause of flu-like symptoms:

• Rapid flu test: A swab test that provides quick results for influenza.
• COVID-19 test: PCR or antigen tests can detect COVID-19. These are available at healthcare facilities, pharmacies, and for at-home use.
• Monospot test: A blood test used to diagnose mono.
• Strep test: A rapid test or throat culture can confirm strep throat.
• Blood tests and imaging: For conditions like pneumonia, blood tests and chest X-rays may be necessary for accurate diagnosis.

When should flu-like symptoms be treated via telehealth?

Telehealth services offer a convenient option for managing flu-like symptoms from home. Here’s when telehealth is a suitable choice:

• Mild symptoms: If symptoms are mild and manageable, a telehealth consultation can provide advice and potential prescriptions.
• Need for symptom relief: A telehealth provider can suggest over-the-counter remedies or prescribe medications to ease symptoms.
• Monitoring chronic conditions: If you have a chronic condition (like asthma or diabetes) and develop flu-like symptoms, a telehealth consultation can help monitor your health.

Telehealth appointment can be a convenient first step, though an in-person visit may be necessary for testing or if symptoms worsen.

When to go to the emergency room?

Certain flu-like symptoms require immediate attention. Go to the ER if you experience:

• Difficulty breathing or shortness of breath
• Persistent chest pain or pressure
• Sudden confusion or inability to stay awake
• High fever (above 39.4°C) that doesn’t improve with medication
• Severe dehydration, shown by dizziness, infrequent urination, or dry skin

FAQs about flu-like symptoms

Can lack of sleep cause flu-like symptoms?

Yes, insufficient sleep can weaken the immune system, making you more susceptible to illness and causing fatigue, headaches, and body aches that mimic flu symptoms.

What If I have flu-like symptoms during pregnancy?

Pregnant women should seek medical advice if they experience flu-like symptoms, as certain infections can pose risks to both mother and baby. Consulting a healthcare provider ensures that symptoms are appropriately managed.

What If I have conjunctivitis and flu-like symptoms?

Conjunctivitis (pink eye) alongside flu-like symptoms could indicate an underlying viral or bacterial infection. Consult a doctor if you notice redness, eye discharge, or if symptoms persist, as these signs may require specific treatment.

Final thoughts

Flu-like symptoms, while common, can be caused by a variety of illnesses that require different treatments. Understanding these illnesses and recognising when to seek medical care, especially during cold and flu season, is essential for effective treatment and prevention. Telehealth can be a valuable resource for initial consultations, while emergency care may be necessary for severe or persistent symptoms. Stay informed and proactive to manage your health effectively.