What Are Flu Symptoms? How They Differ from COVID-19, and How to Treat Them

Flu season comes around every year, and as the cold weather sets in, many people begin to worry about developing symptoms like fever, body aches, and a sore throat. However, in the age of COVID-19, distinguishing between flu and COVID-19 symptoms has become more important—and more confusing—than ever.

This article will break down the common symptoms of the flu, explain how they differ from COVID-19 symptoms, and provide insight into the best ways to treat flu symptoms.

What Is the Flu?

The flu, or influenza, is a contagious respiratory illness caused by influenza viruses. It primarily affects the nose, throat, and sometimes the lungs, causing mild to severe illness. In some cases, especially among vulnerable groups like the elderly, young children, and those with underlying health conditions, it can lead to serious complications like pneumonia or hospitalization.

The flu is typically more severe than the common cold and spreads through droplets when an infected person coughs, sneezes, or talks. Flu viruses constantly mutate, which is why flu vaccines are updated annually to combat the most recent strains.

Common Flu Symptoms

Flu symptoms can vary from person to person, but the following are the most common:

• Fever: A sudden onset of a high temperature (often over 100°F or 37.8°C) is a hallmark symptom of the flu.
• Chills: Many flu sufferers experience chills or shivering alongside a fever.
• Muscle and Body Aches: Muscle pain, particularly in the back, arms, and legs, is a common flu symptom.
• Fatigue and Weakness: The flu can cause extreme tiredness that may last for weeks, even after other symptoms subside.
• Sore Throat: A scratchy or sore throat is common in flu cases.
• Cough: A dry or sometimes productive cough often accompanies the flu.
• Runny or Stuffy Nose: While more common with a cold, nasal congestion can also occur with the flu.
• Headaches: Flu sufferers often report headaches, sometimes accompanied by eye pain or sensitivity to light.
• Gastrointestinal Symptoms: Though more common in children, some adults may experience vomiting or diarrhea with the flu.

Symptoms of the flu usually come on suddenly and can range in severity. In most cases, the flu lasts about one to two weeks, though fatigue can persist longer.

How Flu Symptoms Differ From COVID-19 Symptoms

Since both the flu and COVID-19 are contagious respiratory illnesses, they share many overlapping symptoms. However, there are key differences to consider.

1. Onset of Symptoms

• Flu: Symptoms generally appear suddenly, often within 1 to 4 days after exposure.
• COVID-19: COVID-19 symptoms can take longer to appear, usually within 2 to 14 days after exposure.

2. Loss of Taste or Smell

• Flu: While rare, some flu sufferers may experience a reduced sense of taste or smell due to nasal congestion.
• COVID-19: A sudden loss of taste or smell, without nasal congestion, is one of the more distinctive symptoms of COVID-19 and can occur early in the infection.

3. Breathing Issues

• Flu: Flu patients may experience coughing and chest discomfort, but severe shortness of breath is less common.
• COVID-19: COVID-19 is more likely to cause breathing difficulties and persistent chest pain, especially in severe cases.

4. Severity and Complications

• Flu: In most cases, flu symptoms resolve within a week or two. However, it can cause severe complications in high-risk groups, such as pneumonia or exacerbation of chronic conditions like asthma.
• COVID-19: COVID-19 is more likely to result in severe complications, including respiratory failure, organ damage, and long-term health issues like “long COVID” symptoms, which can last for months after the initial infection.

5. Other Symptoms

• Flu: The flu generally causes more intense muscle aches, headaches, and fatigue.
• COVID-19: COVID-19 patients often report additional symptoms like gastrointestinal problems (nausea, vomiting, diarrhea) and neurological symptoms such as brain fog, confusion, and persistent headaches.

Both illnesses require prompt attention, especially in vulnerable groups, so testing is essential for determining whether someone has the flu or COVID-19.

How to Treat Flu Symptoms

Most cases of the flu can be treated at home with a combination of rest, hydration, and over-the-counter medications. Below are some of the best ways to manage flu symptoms.

1. Rest

Rest is one of the most important ways to help your body recover from the flu. The immune system works best when the body is well-rested, so it’s important to get plenty of sleep and take it easy during the day.

2. Stay Hydrated

Dehydration is common with the flu, especially if you have a fever or are sweating. Make sure to drink plenty of fluids like water, herbal teas, or electrolyte beverages. Avoid alcohol and caffeine, as they can contribute to dehydration.

3. Take Fever and Pain Relievers

Over-the-counter medications like acetaminophen (Tylenol) or ibuprofen (Advil) can help reduce fever and alleviate muscle aches, headaches, and sore throat pain. However, avoid giving aspirin to children and teenagers due to the risk of Reye’s syndrome.

4. Use a Humidifier

A humidifier can help relieve a sore throat, nasal congestion, and coughing by adding moisture to the air. This can ease discomfort, especially when combined with steam from a hot shower.

5. Take Cough Medicines and Lozenges

For coughs, over-the-counter cough medicines can be helpful, but make sure to read the labels carefully. Throat lozenges or honey (for adults and children over 1 year old) can soothe a sore throat.

6. Consider Antiviral Medications

In some cases, a healthcare provider may prescribe antiviral medications, such as oseltamivir (Tamiflu) or zanamivir (Relenza), which can help reduce the severity and duration of the flu if taken within the first 48 hours of symptom onset. These medications are especially useful for high-risk individuals, such as the elderly, pregnant women, and those with chronic health conditions.

7. Stay Isolated

To prevent spreading the flu to others, stay home from work or school, and avoid contact with other people until your fever has been gone for at least 24 hours without the use of fever-reducing medication.

When to Seek Medical Attention for the Flu

While most flu cases can be managed at home, there are certain symptoms that may warrant medical attention:

• Difficulty breathing or shortness of breath
• Chest pain or persistent pressure
• Severe muscle pain or weakness
• Dizziness, confusion, or difficulty staying awake
• Seizures
• Dehydration (no urination for 8 hours, dry mouth, dizziness)

Children, elderly individuals, pregnant women, and those with underlying health conditions are at higher risk of flu complications and should contact a healthcare provider if symptoms worsen.

Best Practices for Preventing the Flu

The best way to protect yourself from the flu is to get vaccinated annually. The flu vaccine is designed to protect against the most common strains of the virus each season and is updated yearly to account for mutations.

In addition to vaccination, the following precautions can help prevent the flu:

• Wash your hands: Regularly washing hands with soap and water for at least 20 seconds can help reduce the spread of flu viruses.
• Avoid touching your face: Flu viruses can enter your body through the nose, eyes, or mouth, so avoid touching your face with unwashed hands.
• Disinfect surfaces: Frequently clean and disinfect high-touch surfaces like doorknobs, countertops, and phones to reduce virus transmission.
• Cover your mouth when coughing or sneezing: Use a tissue or the inside of your elbow to cover your mouth and nose to prevent spreading droplets.

References:

1. Centers for Disease Control and Prevention: Flu Symptoms
2. World Health Organization: Influenza (Seasonal)
3. Mayo Clinic: Flu Treatment
4. Johns Hopkins Medicine: COVID-19 and Flu Differences