Respiratory illnesses are common year-round, but they become especially prevalent during cold and flu season. Two viruses that often cause confusion due to overlapping symptoms are adenovirus and influenza. While both can make you feel miserable, they are not the same illness, and knowing the difference can help you seek the right care at the right time. Understanding how adenovirus and influenza present, how they spread, and when to visit urgent care can make a meaningful difference in recovery and preventing complications.

For same-day illness diagnosis and treatment, visit the walk-in clinic at AFC Urgent Care Elizabeth. Our medical team is available 7 days a week to examine your condition and provide the best treatment. Just walk-in or plan your visit in advance below!

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What is Adenovirus?

Adenovirus is a group of viruses that can cause a wide range of illnesses, particularly affecting the respiratory system. Unlike influenza, adenovirus infections occur throughout the year and are especially common in children, though adults can become infected as well. Adenovirus can spread through close personal contact, respiratory droplets, and contact with contaminated surfaces. It is also known for being more resistant to common disinfectants, making it highly contagious in settings such as schools, daycares, and shared spaces.

Common symptoms of adenovirus include:

• Sore throat
• Runny or stuffy nose
• Cough
• Fever
• Pink eye (conjunctivitis)
• Diarrhea or stomach discomfort (in some cases)

Symptoms may develop gradually and can last longer than a typical cold, especially in young children or those with weakened immune systems.

What is Influenza?

Influenza, commonly known as the flu, is a highly contagious respiratory illness caused by influenza viruses. Flu infections are most common in the fall and winter months and tend to spread rapidly within communities. Unlike adenovirus, the flu often has a sudden onset and can cause more intense, full-body symptoms. While many people recover within 1 to 2 weeks, influenza can lead to serious complications, especially in older adults, young children, pregnant women, and those with chronic medical conditions.

Typical influenza symptoms include:

• Sudden fever and chills
• Severe fatigue
• Body aches and muscle pain
• Headache
• Dry cough
• Sore throat and congestion

Some people may also experience nausea and vomiting, particularly children.

Key Differences in Symptoms and Illness Patterns

Because both viruses can cause sore throat, cough, and fever, telling them apart without testing can be difficult. However, there are some general differences that may offer clues.

Adenovirus infections often:

• Develop more gradually
• Cause lingering symptoms
• Include eye redness or gastrointestinal symptoms

Influenza infections often:

• Begin suddenly
• Cause more intense fatigue and body aches
• Lead to higher fevers

That said, symptom severity varies from person to person and overlap is common, making professional evaluation essential.

When to Seek Testing and Treatment at Urgent Care

If you’re feeling ill and symptoms are interfering with daily life, urgent care can help determine the cause. Many urgent care centers offer rapid flu testing and can evaluate symptoms to rule out other conditions such as strep throat, COVID-19, or RSV. You should consider visiting urgent care if you experience:

• High or persistent fever
• Severe fatigue or body aches
• Difficulty breathing or chest discomfort
• Symptoms that worsen or don’t improve after several days
• Illness in a high-risk individual

If influenza is diagnosed early, antiviral medications may be prescribed to reduce symptom severity and duration. Adenovirus infections are typically managed with supportive care, focusing on symptom relief and hydration.

Get Walk-In Testing & Symptom Relief at AFC Urgent Care Elizabeth

While adenovirus and influenza share many symptoms, they differ in how they develop, how long they last, and how they’re treated. Because it can be difficult to tell them apart at home, testing and evaluation at urgent care provide clarity and peace of mind. Come visit the walk-in clinic at AFC Urgent Care Elizabeth. Early diagnosis allows for appropriate treatment, faster recovery, and reduced risk of spreading illness to others. We offer fast, walk-in care with on-site diagnostic testing and treatment options tailored to your needs. No appointment is necessary! If you have any additional questions about illness treatment, or other services we provide, please contact us directly at (908) 677-5900.