flu MRI what to expect

Overview

Flu (influenza) is a common viral infection of the nose, throat, and lungs. An MRI is a scan that uses magnetic fields to create detailed pictures of the inside of your body. MRI is not used to diagnose flu, but it may be ordered by a doctor to look for complications of flu, such as pneumonia, sinusitis, or inflammation of the brain or heart.

Flu is very common – millions of people get it each year. However, having an MRI for flu is not common. It is only used when a doctor suspects a serious complication or needs a closer look at an area affected by the flu.

Flu can affect anyone, but young children, older adults, pregnant women, and people with chronic health conditions are more likely to develop complications. If complications are suspected, an MRI may be recommended for these higher-risk groups.

Symptoms

Common symptoms

• Fever or chills
• Cough (often dry)
• Sore throat
• Runny or stuffy nose
• Muscle or body aches
• Headache
• Fatigue or extreme tiredness

Symptoms in children

• All the common symptoms above
• Ear pain
• Vomiting or diarrhea
• Poor feeding or decreased activity (in babies)
• Fussiness or crying more than usual

Symptoms in older adults

• Confusion or sudden changes in thinking
• Weakness or dizziness
• Fever may be lower than usual or absent
• Worsening of chronic conditions like heart failure or lung disease

Causes

Main causes

• Influenza viruses – there are two main types, A and B, that cause seasonal flu outbreaks
• The virus spreads through tiny droplets when an infected person coughs, sneezes, or talks
• You can also catch the flu by touching a surface with the virus on it and then touching your mouth, nose, or eyes

Risk factors

• Age – children under 5 and adults over 65 are at higher risk
• Pregnancy, especially in the later months
• Chronic conditions like asthma, diabetes, heart disease, or kidney disease
• A weakened immune system (e.g., from cancer treatment, organ transplant, or HIV)
• Living in a group setting like a nursing home or dormitory
• Obesity

When to see a doctor

See a doctor urgently if:

• Go to urgent care or see your doctor the same day if you have trouble breathing, chest pain, confusion, or severe dehydration
• If you have a high fever that doesn't come down with self-care, or if you feel very weak and can't keep fluids down
• For children – if they have a fever with a rash, are not waking up, or are not drinking enough fluids

Book a routine appointment if:

• If you have flu-like symptoms that are not getting better after a few days
• If you have a chronic health condition and think you have the flu – ask your doctor about early treatment options
• If you have been around someone with the flu and have health risks, ask about preventive measures

Diagnosis

Flu is usually diagnosed by a doctor based on your symptoms and a physical exam. Sometimes a quick swab test from your nose or throat is done to confirm the virus. An MRI is not part of routine flu testing. It is used only if a doctor suspects a complication, like pneumonia, sinus infection, or inflammation of the brain (encephalitis).

Tests that may be done

• Physical exam and health history
• Rapid influenza diagnostic test (nasal swab) – gives results quickly
• Polymerase chain reaction (PCR) test – more accurate, takes a bit longer
• MRI (magnetic resonance imaging) – if a complication is suspected, to look at organs like the brain, heart, or lungs

What to expect at your appointment

If your doctor recommends an MRI, you can expect a safe, painless scan that typically lasts 15 to 60 minutes. You'll lie on a motorized table that slides into a large tube-shaped machine. It's important to remain still. You may be given earplugs or headphones because the machine is loud. In some cases, a dye (contrast material) is injected into a vein to make images clearer. The technician will ask about any metal implants or medical devices before the scan.

Treatment

Treatment for flu focuses on relieving symptoms and letting your body fight the virus. Antibiotics don't work against viruses, but your doctor may prescribe an antiviral medicine if you are at high risk or very sick. This medicine works best if started within 1 to 2 days of symptoms.

Self-care at home

• Rest as much as possible – your body needs energy to heal
• Drink plenty of fluids – water, broth, or herbal tea to prevent dehydration
• Use a humidifier or take a warm shower to help loosen a cough
• Gargle with salt water for a sore throat (but do not swallow)
• Use over-the-counter pain relievers or fever reducers – ask your pharmacist which one is best for you

Medical treatments

Your doctor may prescribe antiviral medication if you are at high risk of complications, are very sick, or have a chronic condition. These medications can shorten the illness and make symptoms milder if taken early. Always follow your doctor's instructions – never share or take someone else's antiviral medicine. The usual care for flu also includes managing fever, cough, and body aches with approved over-the-counter remedies. You should avoid aspirin in children and teenagers due to a serious condition called Reye's syndrome.

When is surgery considered?

Surgery is not needed to treat the flu or for an MRI. In very rare cases where a complication like a sinus abscess or brain swelling requires surgical drainage, surgery may be considered – but this is extremely uncommon.

Living with this condition

While recovering from the flu, plan to stay home from work or school and focus on rest. It's normal to feel tired for a week or two. Don't push yourself back into normal activities too quickly – let your body guide you. Drink fluids regularly and get plenty of sleep.

Lifestyle tips

• Wash your hands often with soap and water, especially after coughing or sneezing
• Cover your mouth and nose with a tissue or your elbow when coughing or sneezing
• Clean frequently touched surfaces like doorknobs and phones
• Stay away from others you care for if you are still contagious – you can spread the flu for up to a week

Diet and exercise

You may not feel like eating much, but try to have light, nutritious foods like soup, yogurt, fruits, and vegetables. Avoid heavy meals and drinking alcohol. Gentle movement like short walks can help as you recover, but avoid intense exercise until you feel fully better.

Mental health and emotional wellbeing

Being sick with the flu can feel lonely and frustrating, especially if you have to stay in bed for days. It's normal to feel anxious or low. Try to stay connected by phone or video calls – talking to friends or family can lift your mood. If sadness or worry lasts beyond your recovery, talk to your doctor.

Prevention

Yes, the flu can often be prevented. The most effective way is to get a flu vaccine every year. Good hand hygiene and avoiding close contact with sick people also help.

Vaccines

The annual flu vaccine is recommended for everyone aged 6 months and older, especially people at high risk and those who care for them. It reduces your chance of getting the flu and makes the illness milder if you still get it. You cannot get the flu from the flu shot.

Screening programmes

There is no routine screening test for the flu. If you have symptoms, testing is done to confirm the cause. Some people at high risk may be tested more often, but this is not a screening program – it’s part of clinical care.

Complications

If left untreated

• Pneumonia – infection and inflammation in the lungs, which can be serious
• Bronchitis – inflammation of the large airways
• Sinusitis and ear infections
• Worsening of chronic conditions like asthma, heart failure, or diabetes
• Inflammation of the heart muscle (myocarditis) or brain (encephalitis) – rare but serious

Long-term outlook

Most people with the flu recover fully within 1 to 2 weeks. Even if complications occur, they are treatable if caught early. Your healthcare team will work with you to monitor and manage any issues. Feeling tired for a week or two after the worst symptoms is common and gets better with rest. You will likely feel like yourself again soon.

Find support

External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.