Covid 19 Basics

Overview

COVID-19 is an illness caused by a virus called SARS-CoV-2 (a type of coronavirus). It mostly affects your nose, throat and lungs, but it can affect other parts of the body too. The virus spreads mainly through tiny droplets and particles that leave a person's mouth and nose when they breathe, talk, cough or sneeze. You can catch it by breathing in those particles in a crowded or poorly ventilated space, or by getting them on your hands and then touching your eyes, nose or mouth. Some people get very mild symptoms, some get flu-like illness, and a small number become seriously unwell.

Yes. Since the virus first appeared in late 2019, it has spread all over the world. It now circulates much like other seasonal respiratory viruses, with waves from time to time. Because most people have had vaccines, previous infection, or both, the illness is usually milder than it was in the early years.

Anyone can catch COVID-19, at any age. It is usually mild in children and healthy adults. The risk of becoming seriously unwell is higher for older adults, people with long-term conditions (such as heart, lung, kidney or liver disease, diabetes, or a weakened immune system), people who are pregnant, and people who smoke or have obesity. Living in crowded housing or working in healthcare can also raise your chance of catching it.

Symptoms

Common symptoms

• Fever or a high temperature
• A new, continuous cough
• Sore throat
• Runny or blocked nose
• Tiredness or exhaustion
• Headache
• Muscle aches and feeling generally unwell
• Loss or change in your sense of smell or taste
• Shortness of breath, especially with activity
• Feeling sick, being sick, or diarrhoea
• A rash on the skin

Symptoms in children

• Often very mild, or no symptoms at all
• Fever and a cough
• Sore throat and runny nose
• Tummy ache, being sick or diarrhoea
• A barking cough or noisy breathing (less common)
• Unusual tiredness or poor feeding in babies

Symptoms in older adults

• May not develop a fever at all
• New confusion or drowsiness
• Falls or unsteadiness
• Not eating or drinking as usual (risk of dehydration)
• Breathlessness that gets worse over a few days
• Existing health problems, such as heart or lung conditions, getting worse

Causes

Main causes

• Infection with the SARS-CoV-2 virus
• Breathing in tiny droplets or particles from someone who is infected, especially indoors with poor airflow
• Close, prolonged contact with an infected person, such as living in the same household
• Touching surfaces that have the virus on them and then touching your eyes, nose or mouth (this is a less common route)

Risk factors

• Being older, especially over 70
• Having a long-term condition such as diabetes, heart disease, lung disease, kidney or liver disease
• Having a weakened immune system, for example from some medical treatments
• Being pregnant
• Smoking or having obesity
• Living in crowded or shared housing
• Working in health or social care
• Not being up to date with recommended vaccinations

When to see a doctor

See a doctor urgently if:

• You have any of the emergency warning signs listed above — call your local emergency number straight away
• Your breathing is getting worse, or you feel breathless at rest
• You cannot keep fluids down, or you feel very dizzy and weak
• You are in a higher-risk group and your symptoms are getting worse
• Your child is unusually sleepy, not drinking, or has fewer wet nappies

Book a routine appointment if:

• You are unsure whether your symptoms need checking
• You have a health condition that makes you higher risk, and you want advice early on
• Symptoms have not settled after about four weeks
• You are pregnant and develop a fever or feel unwell
• You need advice about work, school or caring for others

Diagnosis

Your doctor will usually ask about your symptoms and whether you have been in contact with someone who has COVID-19. The infection is confirmed with a simple test that looks for the virus in a swab from your nose and throat, or sometimes in saliva. Many people test at home with a rapid test bought from a pharmacy. If you become unwell in hospital, other tests may be done to check how well your lungs and other organs are working.

Tests that may be done

• A rapid antigen test (lateral flow test) on a nose or throat swab, with results in about 15 to 30 minutes
• A PCR test, where the sample is sent to a laboratory for a more sensitive result
• A blood oxygen reading using a small clip on your finger (pulse oximeter)
• Blood tests to check how your body is coping
• A chest X-ray or scan if there are concerns about your lungs

What to expect at your appointment

A home test is quick and private. You swab the inside of your nose (and sometimes your throat), place the swab in a small tube of liquid, and put drops onto the test strip. Waiting lines appear within minutes. If you are seen in a clinic or hospital, staff may check your temperature, breathing, blood pressure and oxygen levels. None of these tests are painful, though the swab can tickle or make your eyes water for a moment.

Treatment

There is no cure that works for everyone, but most people get better with simple supportive care at home. Treatment is about helping your body rest and recover while watching for signs that you need more help. People at higher risk of becoming seriously unwell may be offered extra monitoring or specialist medicines by a healthcare professional. Because recommendations change over time, always follow the advice of your own doctor or pharmacist.

Self-care at home

• Rest as much as you need — it is normal to feel exhausted for a while
• Drink plenty of fluids, and eat small meals if your appetite is low
• Take paracetamol or ibuprofen if you can safely take them, following the label or your pharmacist's advice — never more than the stated dose
• Keep rooms ventilated by opening windows, and stay home while you feel unwell
• Check your breathing — if you can, use a finger oxygen monitor if one is available and follow the guidance that comes with it
• Sleep propped up if lying flat makes your cough worse
• Ask someone to check in on you by phone if you live alone

Medical treatments

For most people, no specific medical treatment is needed. If you are at higher risk, your doctor may assess you and consider treatments that help your immune system fight the virus, given in hospital or sometimes at home. In hospital, care focuses on supporting your breathing — for example with extra oxygen — monitoring your organs, and treating complications such as blood clots or infection. Your medical team will explain any treatment they recommend, why it is right for you, and what to expect.

When is surgery considered?

Surgery is not used to treat COVID-19 itself. Occasionally, if a rare complication develops, such as a severe lung or heart problem, a specialist team may discuss procedures. Your doctors would explain this fully if it ever applied to you.

Living with this condition

While you are unwell, keep life simple. Sleep when you need to, drink regularly, and do not push yourself to return to normal activity too fast. Many people find the tiredness lingers for a couple of weeks after other symptoms fade. Build back gently — short walks, light housework, then more as you feel able. If symptoms drag on beyond four weeks, it is worth speaking to your doctor, who can check for other causes and help you manage your energy.

Lifestyle tips

• Aim to return to gentle daily movement gradually rather than all at once
• Keep up good hand hygiene and ventilate rooms when you have visitors
• Avoid smoking and vaping, which make breathing problems more likely
• Stay up to date with recommended vaccinations
• Keep a simple note of your symptoms and energy levels to spot patterns
• Plan rest breaks into your day if you are back at work or caring for others

Diet and exercise

There is no special diet that treats COVID-19, but eating regularly and drinking enough helps your body recover. If your appetite is poor, try small snacks more often, and choose things that are easy to eat. Once you feel better, build exercise back slowly — walking, stretching and light activity first. Avoid intense exercise until you feel fully recovered, and stop if you become breathless, dizzy or unusually tired.

Mental health and emotional wellbeing

Being ill, isolating, and worrying about others can all affect your mood. Feeling anxious, low, frustrated or cut off is very common and usually settles as you recover. Keep in touch with people by phone or video, and be honest with your doctor if you are struggling — support is available. If you ever have thoughts of harming yourself, contact your local emergency number or a crisis support service straight away; you deserve help quickly.

Prevention

You cannot always avoid catching COVID-19, but you can lower the chance. The virus spreads most easily in crowded, stuffy indoor spaces, so fresh air matters. Opening windows, meeting outdoors or in well-ventilated rooms, washing your hands regularly, and covering coughs and sneezes all help. If you are unwell, staying home and away from vulnerable people protects them.

Vaccines

Vaccines are available and have been shown to reduce the risk of becoming seriously ill, needing hospital care, or dying from COVID-19. Which vaccine and how often it is offered depends on your age, health conditions and where you live, and recommendations are updated regularly. Ask your doctor, nurse or pharmacist what is recommended for you and your family. Vaccination is safe for most people, including during pregnancy.

Screening programmes

There is no routine screening programme for COVID-19. Testing is used to check whether you currently have the virus — for example if you have symptoms, or before visiting someone at high risk. Your local health service can tell you where tests are available and who is eligible for free testing.

Complications

If left untreated

• Pneumonia, where the lungs become inflamed and filled with fluid
• Low oxygen levels, which may need oxygen treatment in hospital
• Blood clots in the legs or lungs
• Worsening of existing heart, lung, kidney or liver conditions
• Long COVID — symptoms such as tiredness, breathlessness and brain fog lasting weeks or months
• Rarely, inflammation affecting other parts of the body, including in children

Long-term outlook

Most people make a full recovery. For many, COVID-19 feels like a bad cold or flu and settles within one to two weeks. Some people need longer to get their energy back, and a smaller number have ongoing symptoms that improve slowly with support. Vaccination and good general health make serious illness much less likely. If you are worried at any point, reach out to your healthcare team — help is there, and recovery is the usual outcome.

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