The most common cause of epiglottitis is the Haemophilus influenzae type b (Hib) bacteria.
Children are particularly vulnerable to a Hib infection because they have an underdeveloped immune system (the body’s natural defence against infection and illness). Hib can cause a number of serious infections, including:
- epiglottitis
- pneumonia (infection of the lungs)
- meningitis (infection of the outer membranes of the brain)
Due to the success of the Hib vaccination programme, Hib-related infections are rare. However, occasionally the vaccination does not work and this can result in someone being infected.
The Hib bacteria is spread in a similar way to cold or influenza (flu) viruses. People who are infected with the Hib bacteria (most of whom will not have any symptoms) can spread the virus when they cough or sneeze by releasing tiny droplets of saliva and mucus that contain the virus.
The infected droplets can also contaminate surfaces and objects. Anyone who places their hand on a contaminated surface or object and then touches their face or mouth may develop an infection.
Other causes
Less common causes of epiglottitis include:
- other bacterial infections, such as streptococcus pneumoniae (a common cause of pneumonia)
- fungal infections – people with a weakened immune system are most at risk from these types of infection
- the varicella zoster virus – the virus responsible for chickenpox
- trauma to the throat – such as a blow to the throat, or burning the throat by drinking very hot liquids
- smoking illegal drugs, such as cannabis or crack cocaine
