Sore throat, strep throat or tonsillitis: what’s the difference?

When you have a sore throat, the lining of the inside of your throat is inflamed or swollen as your body’s response to infection with a virus or bacteria. As your throat swells, it becomes dry, which can make eating and drinking uncomfortable, and make your voice become hoarse. 

A frequent cause of sore throats is the common cold, which is caused by a viral infection and usually also leads to a runny, congested nose. Strep throat is a specific bacterial infection that can cause a sore throat too; however, unlike the common cold, it doesn’t usually cause nasal symptoms. 

Tonsillitis is inflammation of the tonsils at the back of your throat due to a viral or bacterial infection, and will also make your throat sore, in addition to other symptoms.

Here, we’ll take a closer look at strep throat, tonsillitis and the common cold as causes of a sore throat, as well as how to spot the difference. 

Strep throat

Strep throat is a very common infection and rarely causes serious health problems. It’s caused by infection with the bacteria Streptococcus pyogenes, which is also known as group A streptococcus. 

Strep throat infections usually occur soon after a viral infection when your immune system is weakened. It can cause a sore throat, fever, loss of voice, difficulty swallowing and a bright red, bumpy rash all over your body. It can also lead to tonsillitis. 

Tonsillitis

This refers to swelling of the tonsils, the two round, soft, pinkish pieces of tissue that sit at the back of your throat. The tonsils help filter out germs that enter your body via your nose and mouth. 

Tonsillitis is usually caused by infection with the common cold or flu (viral infections), but it can also be caused by strep throat.

When your tonsils swell, eating and drinking become painful. You may also notice white pus-filled dots on your tonsils and swelling of the lymph glands in your neck, such that they feel tender to touch. A fever is another common symptom of tonsillitis.

In some cases, tonsillitis can keep happening, which means you develop tonsillitis several times per year. If you end up missing a lot of work or school and you get tonsillitis more than seven times in a year or have lots of infections year-on-year, your tonsils may need to be removed. 

Common cold

Everyone catches colds. In most cases, they are caused by an infection with rhinoviruses but can also be caused by coronaviruses and respiratory syncytial viruses. 

Symptoms of a common cold include a sore throat, sneezing, and a runny, congested nose. A fever doesn’t always develop and if it does occur, is usually mild. 

As mentioned earlier, infection with a common cold can lead to tonsillitis. 

How these infections spread

Strep throat is spread through direct contact with droplets from a cough or sneeze, which can land on surfaces or body parts, or direct contact with weeping sores that can develop as part of the skin rash caused by strep infection. 

The common cold is also spread through droplets from a cough or sneeze but unlike strep throat can’t be spread through skin contact. 

In children, keeping up with vaccinations can reduce their risk of developing strep throat by preventing other infections (eg measles, meningitis) that will weaken their immune system and leave them more vulnerable to group A streptococcus infections. 

Treating a common cold, strep throat and tonsillitis

In most cases, strep throat, a common cold and tonsillitis will get better on their own. However, you can take steps to relieve your symptoms as you recover. 

Treating a common cold

Taking regular over-the-counter painkillers (ie paracetamol and ibuprofen), drinking lots of water and taking lozenges containing a local anaesthetic will all help relieve your symptoms. 

You can also use over-the-counter saltwater nose rinses to help remove the excess mucus in your nose and sinuses. Steam inhalation using plain, warm water can also help remove the mucus. 

Decongestant nasal sprays can help; however, it is important to only use these for the most acute period of your infection and for no longer than five days — prolonged use can worsen nasal congestion. 

Treating strep throat

Strep throat can settle without antibiotics, but if you start to have a very high fever, and struggle to eat and drink, a course of antibiotics may be needed. 

During your recovery, you can also take over-the-counter painkillers and lozenges to soothe your sore throat. Make sure you rest and drink lots of water too.

Treating tonsillitis

Drinking cool drinks and gargling with warm salt water can help soothe your throat. Make sure you rest well, drink lots of water, and if you feel uncomfortable, take regular over-the-counter painkillers. 

Throat sprays and lozenges containing a local anaesthetic can also help relieve your symptoms. 

If your symptoms don’t improve after four days, see your GP. 

While tonsillitis is usually caused by a viral infection, in some cases, it can be caused by a bacterial infection. Your GP can swab your tonsils to test whether or not your infection is viral or bacterial if they are not sure. If it is bacterial, they may prescribe a course of antibiotics to help speed up your recovery.  

Tonsillitis can sometimes lead to the development of an abscess (a pus-filled sac) behind your tonsils. This can cause severe throat pain, ear pain on one side, a change in your voice and an inability to swallow any liquids due to the pain. In this case, see your GP; they may refer you to an ENT surgeon to have the abscess drained. 

When to see a doctor

In both children and adults, strep throat can cause serious illness. If your child is aged under five and has a persistent fever, is not eating, drinking or sleeping well, has muscle aches, or is behaving differently, see your GP or call 111. They may need a course of antibiotics. 

In adults, if you have a persistent fever with severe neck and joint pain, which is not relieved by over-the-counter painkillers or you can’t eat or drink, you should also see your GP.