flu result meanings for patients

Overview

The flu (short for influenza) is a common viral infection of the nose, throat, and lungs. A flu test helps find out if you have the flu virus. The result tells you whether the virus was detected in your sample. A positive result means you likely have the flu. A negative result means the virus was not found, but you could still have the flu if the test was done very early or not done well.

Yes, the flu is very common. Every year, millions of people worldwide get the flu, especially during the autumn and winter months.

Anyone can get the flu, but it can be more serious in young children, older adults (65+), pregnant women, and people with chronic health conditions like asthma, heart disease, or diabetes.

Symptoms

Common symptoms

• Fever or feeling feverish/chills
• Cough (often dry)
• Sore throat
• Runny or stuffy nose
• Body aches and tiredness
• Headache
• Some people may have vomiting and diarrhoea, though this is more common in children

Symptoms in children

• Same cold-like symptoms plus fussiness, loss of appetite, and sometimes high fever (over 39°C / 102°F)
• Children may also get ear infections or pneumonia
• Feeling very tired or irritable

Symptoms in older adults

• Fever may be lower, but confusion, dizziness, or worsening of existing health conditions (like heart failure) can occur
• Less energy, less thirst, muscle weakness
• Higher risk of complications such as pneumonia

Causes

Main causes

• Influenza viruses (types A and B are the main ones that cause seasonal flu)
• Spread from person to person when someone coughs, sneezes, or talks, releasing tiny droplets that others breathe in

Risk factors

• Being around many people during flu season (e.g., living in a nursing home, going to school, using public transport)
• Not getting the yearly flu vaccine
• Having a weakened immune system
• Chronic conditions such as asthma, diabetes, heart disease, or kidney disease
• Pregnancy
• Age: children under 5 and adults over 65 are at higher risk for serious illness

When to see a doctor

See a doctor urgently if:

• If you have emergency symptoms listed above (call your local emergency number)
• If your symptoms are very severe, such as high fever that does not come down with basic measures, or you are coughing up blood

Book a routine appointment if:

• If you have flu symptoms and are in a high-risk group (e.g., very young, older, pregnant, chronic condition), even if symptoms are not severe, talk to your doctor for guidance
• If you are unsure about your test result or need help understanding what to do next

Diagnosis

A doctor or nurse uses a long, soft swab to gently wipe the inside of your nose or the back of your throat. The swab is then tested for the flu virus. There are two main types: a rapid test (result in about 15 minutes) and a PCR test (sent to a lab, result in 1–3 days). Sometimes the rapid test may miss the flu (false negative), especially if the swab was not done well or if you are very early in the illness. PCR tests are more accurate.

Tests that may be done

• Rapid influenza diagnostic test (RIDT)
• Reverse transcription‑polymerase chain reaction (PCR) test – this is the most accurate

What to expect at your appointment

The test takes only a few seconds. You may feel a tickle or a brief discomfort when the swab goes into your nose or throat. You can go home right after. If your test is positive, you will likely be advised to rest, drink fluids, and isolate to avoid spreading the virus. If negative but you still have symptoms, your doctor may do another test or treat you for flu based on your symptoms.

Treatment

Treatment for the flu focuses on easing symptoms and helping your body fight the virus. Most people get better with rest and home care. Antiviral medicines can be prescribed by a doctor, especially for people at high risk of complications. These work best when started within 48 hours of symptoms starting. Antibiotics do not work against the flu (it is a virus, not a bacteria).

Self-care at home

• Get plenty of rest – your body needs energy to fight the virus.
• Drink lots of fluids (water, clear soup, herbal tea) to prevent dehydration.
• Use a cool-mist humidifier or take a steamy shower to ease a cough or stuffy nose.
• Take over‑the‑counter pain relievers like paracetamol or ibuprofen for fever and body aches (always follow the dose on the label).
• Do not smoke or vape – it can make symptoms worse.

Medical treatments

If you are at high risk (e.g., pregnant, elderly, or have a chronic condition) or have severe symptoms, your doctor may prescribe an antiviral medicine. These medicines can shorten the illness and make it milder. They are usually taken by mouth for 5 days. Antivirals are not a substitute for the flu vaccine. Always take medicines exactly as prescribed.

When is surgery considered?

Surgery is not used to treat the flu. If complications like pneumonia or sinus infections develop, you may need additional treatments, but these are usually medicines, not surgery.

Living with this condition

While you have the flu, stay home from work, school, and public places until you have been fever‑free (without using fever‑reducing medicine) for at least 24 hours. Cover your mouth and nose when you cough or sneeze with a tissue or your elbow. Wash your hands often. Keep your distance from others in your home if possible.

Lifestyle tips

• Get plenty of sleep and rest.
• Avoid alcohol and caffeinated drinks because they can dehydrate you.
• Use simple activities like reading or listening to calm music to help pass the time while recovering.

Diet and exercise

Eat light, easy‑to‑digest foods like soup, crackers, or toast if you feel like eating. Do not force yourself to exercise; your body needs rest to recover. Once you are feeling better, slowly return to normal activity. Gentle stretching or short walks can help, but stop if you feel tired.

Mental health and emotional wellbeing

Being sick with the flu can make you feel worried, lonely, or down. It is normal to feel this way. You may need to isolate, which can increase feelings of sadness or anxiety. If you feel overwhelmed, talk to a friend or family member by phone or video call. If these feelings last beyond your recovery or interfere with daily life, speak to a healthcare provider.

Prevention

Yes, the flu can often be prevented. The best way is to get a flu vaccine every year. You can also reduce your risk by washing your hands often, avoiding close contact with sick people, and not touching your face.

Vaccines

The flu vaccine is recommended every year for everyone aged 6 months and older, especially those at high risk. It is usually given as a shot or a nasal spray. The vaccine changes each year to match the viruses that are expected to be most common. It takes about two weeks for your body to build protection. Even if you get the flu after vaccination, it is usually milder.

Screening programmes

Routine screening for the flu is not needed. If you have symptoms and are in a high‑risk group, your doctor may recommend testing.

Complications

If left untreated

• Pneumonia (infection of the lungs) – a common complication that can be serious
• Sinus infections or ear infections
• Worsening of chronic conditions like asthma, diabetes, or heart failure
• In rare cases, encephalopathy (brain swelling) or myocarditis (heart muscle inflammation)
• Dehydration, especially in young children and older adults

Long-term outlook

Most people with the flu recover fully within 1 to 2 weeks, even without specific treatment. However, some people, especially those in high‑risk groups, can develop severe illness. Getting vaccinated, resting, and seeking medical care early if you are at high risk helps prevent complications. With proper care, the outlook for almost everyone is good.

Find support

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