“My throat hurts.” “I can’t stop coughing and my nose won’t stop running.” “I suddenly spiked a fever.” — When symptoms like these appear, it can be difficult to tell on your own whether you have a common cold, the flu, or COVID-19.
While most colds resolve on their own, influenza is a condition where early use of antiviral medication can help reduce the severity of symptoms. Because other illnesses — such as COVID-19 and bacterial infections — require different approaches, getting an appropriate evaluation based on your symptoms and their progression is important.
Keldsen Family Clinic is a family-oriented clinic offering both Psychosomatic Medicine and Internal Medicine, a 1-minute walk from ‘Oizumi Yubinkyoku’ bus stop, accessible by Seibu Bus from Oizumi-Gakuen Station. We are open on weekends and holidays and also offer telemedicine. If you are concerned about fever, coughing, or a sore throat, please do not hesitate to reach out.
About Acute Upper Respiratory Infections
Conditions such as the common cold, influenza, and COVID-19 are collectively referred to in medical terms as “acute upper respiratory infections.” These occur when viruses or bacteria infect the upper respiratory tract — the airways including the nose, throat, and trachea — causing inflammation.
The vast majority are caused by viruses, with over 200 different types identified. This is precisely why there is no specific cure for the common cold — the standard approach is to manage symptoms while the body heals on its own.
On the other hand, antiviral medications are available for influenza and COVID-19. When diagnosed early, these medications may help shorten the duration of symptoms and reduce the risk of severe illness. Rather than dismissing symptoms as “just a cold,” it is important to see a doctor promptly when warranted.
At Keldsen Family Clinic, we carefully review the progression of your symptoms, perform tests when appropriate, and recommend the most suitable treatment plan.
What Are the Differences Between a Cold, the Flu, and COVID-19?
Common Cold
A cold is inflammation of the upper respiratory tract caused by a variety of viruses, including rhinoviruses, adenoviruses, and seasonal coronaviruses.
Key features:
- Symptoms tend to develop gradually
- Primarily involves a runny nose, nasal congestion, sneezing, and mild sore throat
- Fever, if present, is usually low-grade
- General fatigue is mild
- Recovery typically occurs within a few days to one week
Influenza
Influenza is an infection caused by influenza viruses (type A and type B), with outbreaks occurring primarily during the winter months each year.
Key features:
- Sudden onset of high fever (38°C / 100.4°F or higher)
- Intense fatigue, muscle pain, and joint pain
- Headache
- Sore throat and cough
- Runny nose (often appearing slightly later)
- Risk of complications such as pneumonia and encephalopathy in severe cases
COVID-19
With recent circulating variants, the way symptoms present has been changing.
Key features:
- Severe sore throat is often the primary complaint
- Fever, cough, fatigue, and headache
- Loss of taste and smell has become less common but may still occur
- Even mild cases tend to have symptoms lasting about one week
How to Tell Them Apart
- Gradual onset with nasal symptoms suggests a common cold
- Sudden high fever with systemic symptoms suggests influenza
- Severe sore throat combined with local outbreak patterns suggests COVID-19
That said, it is difficult to distinguish these conditions based on symptoms alone. A doctor will make a clinical judgment taking into account current outbreak trends and the progression of symptoms. In some cases, testing for influenza or COVID-19 can provide a definitive diagnosis.
Features and Symptoms of Colds and Infectious Diseases
Symptoms of infectious diseases vary from person to person and can range from mild to severe.
Specific Symptoms
Upper Respiratory Symptoms
- Runny nose, nasal congestion, and sneezing
- Sore throat or throat discomfort
- Cough and phlegm
- Hoarseness
- Ear pain or discomfort
Systemic Symptoms
- Fever (ranging from low-grade to high)
- Chills
- Fatigue and malaise
- Headache, muscle pain, and joint pain
- Loss of appetite
- Nausea and diarrhea (depending on the type of virus)
Complications to Watch For
- Bronchitis or pneumonia: Prolonged coughing, shortness of breath, chest pain
- Sinusitis: Yellow nasal discharge, pain in the cheeks or forehead, persistent nasal congestion
- Otitis media (middle ear infection): Ear pain, difficulty hearing
- Worsening of asthma: Shortness of breath, wheezing
When to Seek Medical Attention Promptly
- Fever of 38°C (100.4°F) or higher lasting 3 to 4 days or more
- Difficulty breathing or chest pain
- Inability to take fluids or signs of dehydration
- Confusion or drowsiness
- Fever in elderly individuals or those with underlying health conditions
- Fever during pregnancy
- Prolonged fever in young children
Treatment and Management of Colds and Infectious Diseases
For most colds, there is no specific cure, and treatment focuses on relieving symptoms (symptomatic therapy). For influenza and COVID-19, antiviral medications may be an option.
1. Treatment for the Common Cold (Symptomatic Therapy)
Cold medications do not eliminate the virus itself — they are designed to help ease uncomfortable symptoms.
- Antipyretics and analgesics: For fever, headache, and sore throat
- Expectorants: To help loosen and clear phlegm
- Antitussives (cough suppressants): For persistent or troublesome coughing
- Antihistamines: For a runny nose and sneezing
Getting adequate rest and allowing your immune system to fight off the virus is the cornerstone of treatment.
2. Treatment for Influenza
Anti-influenza medications, when taken within 48 hours of symptom onset, may help suppress viral replication, shorten the duration of fever, and reduce the risk of severe illness.
- Oseltamivir (Tamiflu): Oral medication
- Zanamivir (Relenza): Inhaled medication
- Baloxavir marboxil (Xofluza): Single-dose oral medication
- Laninamivir (Inavir): Inhaled medication
If influenza is suspected, seeking medical attention early is important.
3. Treatment for COVID-19
For those with mild symptoms, treatment primarily focuses on symptom management. However, antiviral medications may be used for individuals at higher risk of severe illness.
- Molnupiravir (Lagevrio)
- Nirmatrelvir/ritonavir (Paxlovid)
- Ensitrelvir (Xocova)
These medications have specific eligibility criteria and are prescribed at the discretion of a physician.
4. About Antibiotics
Colds are almost always caused by viruses, and antibiotics are not effective against them. Using antibiotics for a cold is generally not recommended, as it may cause side effects and contribute to antibiotic resistance.
However, if a secondary bacterial infection develops — such as bacterial pneumonia, otitis media, or sinusitis — antibiotics may be appropriate.
5. Self-Care and Prevention
Self-Care During Recovery
- Get plenty of rest and sleep
- Stay hydrated: To prevent dehydration
- Eat easy-to-digest foods: Such as porridge or soup
- Keep your room humidified: To prevent throat dryness
- Wear a mask: To help prevent spreading the infection to others
Preventing Infectious Diseases
- Wash your hands and gargle regularly
- Wear a mask during outbreaks or in crowded places
- Maintain adequate sleep and nutrition to support your immune system
- Get vaccinated: Discuss influenza, COVID-19, pneumococcal, and other vaccines with your doctor
- Ensure good ventilation and humidity control indoors
Colds, influenza, and COVID-19 can be difficult to tell apart, and depending on the symptoms, early treatment may be crucial. If you are experiencing fever or severe sore throat, or if you are feeling unwell during outbreak season, please do not hesitate to reach out to Keldsen Family Clinic. We are a 1-minute walk from ‘Oizumi Yubinkyoku’ bus stop, accessible by Seibu Bus from Oizumi-Gakuen Station, open on weekends and holidays, and also offer telemedicine.