Common Cold and Flu
نزلات البرد والإنفلونزا
Both are viral respiratory infections, but influenza (flu) tends to come on more suddenly and cause more severe symptoms — high fever, body aches, and fatigue — than the common cold, which usually causes milder symptoms like a runny nose and sore throat. Most cases resolve with rest and fluids.
This information is for general awareness only and does not replace professional medical advice. Consult a doctor for diagnosis and treatment.
Quick answer
The common cold and influenza (flu) are both viral infections of the nose, throat and airways. Colds are usually milder, with a runny nose, sneezing and sore throat. Flu tends to start suddenly with fever, body aches and marked tiredness.
Most healthy people recover at home in about a week with rest, fluids and simple symptom relief. Antibiotics do not work against viruses.
Flu can be serious in young children, pregnant women, older adults and people with chronic conditions. Seek medical care for difficulty breathing, chest pain, confusion, dehydration, or symptoms that worsen after improving.
Symptoms
Runny or blocked nose and sneezing
Typical of a cold.
Sore throat
Cough
Fever
Higher and more sudden with flu.
Body aches and chills
Marked in flu.
Tiredness and headache
Flu can cause extreme tiredness for days.
Loss of appetite
Symptom guides
Causes and risk factors
Causes
- Cold viruses — Rhinoviruses and other viruses; more than 200 types cause colds.
- Influenza viruses — Types A and B cause seasonal flu.
- Spread through droplets and contact — Coughs and sneezes, and touching contaminated surfaces then the face.
Risk factors
- Close contact with people who are ill
- Young children and crowded settings
- Older age (for flu complications)
- Pregnancy
- Chronic conditions — Asthma, heart, lung, kidney or liver disease, diabetes.
- Weakened immune system
How is it diagnosed?
Colds and flu are usually diagnosed from symptoms, especially during flu season. Tests are used when the result would change management.
Symptom assessment
Onset, fever, body aches and how unwell you feel, along with local flu activity.
Rapid flu or PCR tests
Considered in high-risk patients, during outbreaks, or hospital care.
Chest examination and X-ray
If pneumonia or another complication is suspected.
Related tests
Treatment
Most people need only supportive care. For flu, doctors may prescribe antiviral medicines to selected patients — usually people at higher risk, treated early.
Rest and fluids
Symptom relief
Simple pain and fever relief, saline nose drops or sprays, and throat soothers, as advised by a pharmacist or doctor.
Antivirals for flu
For high-risk patients or severe illness; most effective when started early.
Avoid unnecessary antibiotics
They don't work against colds or flu.
Stay home while unwell
To avoid spreading infection.
Don't give aspirin to children or teenagers, and check with a pharmacist before giving cold medicines to young children.
When should you see a doctor?
Arrange a medical assessment if
- Symptoms lasting more than about ten days, or improving then worsening
- High fever lasting more than three days
- A young child, pregnant woman or older adult with flu-like illness
- You have a chronic condition such as asthma, heart disease or diabetes
- Ear pain, or persistent sinus pain and green nasal discharge with fever
Seek urgent care if
- Difficulty breathing or shortness of breath
- Chest pain or pressure
- Confusion, severe drowsiness or fainting
- Signs of dehydration — very little urine, dizziness
- In babies: refusing feeds, blue lips, or unusual floppiness
Prevention
Annual flu vaccination
Recommended especially for higher-risk groups.
Wash hands often
Cover coughs and sneezes
Use a tissue or your elbow.
Avoid close contact with people who are ill
Stay home when sick
Frequently asked questions
What is the difference between a cold and flu?
Colds come on gradually and are usually mild — runny nose and sore throat. Flu is more sudden and severe, with fever, aches and marked tiredness.
How long do colds and flu last?
A cold usually lasts about a week; flu often improves in a week, though tiredness and cough can linger.
Do antibiotics help colds and flu?
No. They act against bacteria, not viruses.
Is the flu vaccine effective?
It reduces the risk of flu and of serious complications, though protection varies by year and person. It is recommended annually for higher-risk groups.
When am I contagious?
You can spread the virus from about a day before symptoms until several days after.
Can flu be dangerous?
Yes, especially for young children, older adults, pregnant women and people with chronic illnesses; it can lead to pneumonia.
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