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Disease

Haemophilus influenzae type b (Hib)

Hib is an infection that can cause serious illness, caused by the bacteria known as Haemophilus influenzae type b (Hib). Despite its name, Hib is not related to influenza (‘the flu’).

Page last updated 16 November 2023

Hib bacteria can live harmlessly in the throat of healthy people and cause no issues. However, an infected person does not need to experience symptoms to spread the bacteria to others. Hib bacteria can spread from one person to another when an infected person coughs or sneezes. If the Hib bacteria happens to move to other parts of the body (i.e. lungs or bloodstream), it can cause more serious diseases. 

Babies and young children less than 5 years of age are at the greatest risk of serious illness from Hib, which can cause lifelong disability or lead to death. In Australia, Hib has become a rare disease due to the routine immunisation of infants. Reported cases of Hib have fallen from 549 cases in 1992 to 16 cases in 2017.

Hib disease is a serious bacterial infection that can be life-threatening. While the Hib bacteria can live harmlessly in the throat of healthy people, if it does spread and move on to other parts of the body (i.e. lungs or bloodstream), it can cause some serious complications, such as:

  • meningitis (inflammation of the lining of the brain and spinal cord)
  • epiglottitis (inflammation of the flap and the top of the windpipe) 
  • pneumonia (infection of the lungs)
  • osteomyelitis (infection of the bones and joints)
  • cellulitis (infection under the skin, usually on the face).

Commonly asked questions

What is Hib disease?

Hib disease is a serious bacterial infection that can be life-threatening.

    While the Hib bacteria can live harmlessly in the throat of healthy people, if it does spread and move on to other parts of the body (i.e. lungs or bloodstream), it can cause some serious complications, such as:

    • meningitis (inflammation of the lining of the brain and spinal cord)
    • epiglottitis (inflammation of the flap and the top of the windpipe) 
    • pneumonia (infection of the lungs)
    • osteomyelitis (infection of the bones and joints)
    • cellulitis (infection under the skin, usually on the face).
    How is Hib spread?

    Hib is spread from person to person by coughing or sneezing or other secretions from an infected persons nose or throat. Once infected, a person can develop symptoms of Hib quite rapidly (around 2-4 days).

    It is important to remember that you don’t need to show any symptoms to be able to spread Hib on to others. The bacteria can live harmlessly in your throat, only causing severe illness in vulnerable groups, like young children under the age of 5 years old.

    You can remain infectious with Hib for as long as the bacterium is present in your nose or throat. People with Hib require 48-72 hours of antibiotic treatment before they’re considered no longer infectious.

    Is Hib a virus or bacterium?

    Despite its name (Haemophilus influenzae type b), Hib is a bacterial disease and is not a form of influenza (flu), which is caused by a virus.

    What are the symptoms of Hib disease?

    Some people infected with Hib do not show any symptoms. For those who do, the type of symptoms depend on the part of the body that is infected:

    • Brain (meningitis) – inflammation of the lining of the brain and spinal cord. Symptoms include fever, headache, stiff neck, nausea, vomiting and drowsiness. Convulsions or seizures may also occur.
    • Lungs (pneumonia) – infection of the lungs. Symptoms include shortness of breath, fever, lack of energy, loss of appetite, headache, chest pain and cough.
    • Windpipes (epiglottitis) – inflammation of the windpipe. Symptoms include difficulty breathing and swallowing, pale colour and fever.
    • Bones and joints (osteomyelitis) – infection of the bones and joints. Symptoms include swelling, inflammation and pain over the affected bone.
    • Skin (cellulitis) – infection of the skin or soft tissue. Symptoms in the affected area include redness, heat, swelling and tenderness. There may also be a discharge of fluid or pus. 
    Are there any complications of the Hib infection?

    Yes, complications of Hib infection can develop quickly and, if left untreated, can be life-threatening.
     

      Some complications include:

      • meningitis (inflammation of the lining of the brain and spinal cord)
      • epiglottitis (inflammation of the flap and the top of the windpipe) 
      • pneumonia (infection of the lungs)
      • osteomyelitis (infection of the bones and joints)
      • cellulitis (infection under the skin, usually on the face)

      Sources & Citations

      1. Australian Government. Australian Institute of Health and Welfare. Hib disease in Australia. Available at: https://www.aihw.gov.au/getmedia/f2da685b-271c-4200-a875-ccf87f749145/aihw-phe-236_Hib.pdf.aspx (accessed 24 November 2021).
      2. Australian Government Department of Health. Australian Immunisation Handbook. Haemophilus influenzae type b (Hib). Available at: https://immunisationhandbook.health.gov.au/vaccine-preventable-diseases/haemophilus-influenzae-type-b-hib (accessed 24 November 2021).
      3. Queensland Health. Haemophilus Influenzae type b (Hib). Available at: http://conditions.health.qld.gov.au/HealthCondition/media/pdf/14/33/67/haemophilus-influenzae-type-b-hib-v11 (accessed 24 November 2021).
      4. Centres for Disease Control and Prevention. Vaccine (Shot) for Hib. Available at: https://www.cdc.gov/vaccines/parents/diseases/hib.html (accessed 24 November 2021).
      5. Better Health Channel. Haemophilus influenzae type B (Hib). Available at: www.betterhealth.vic.gov.au/health/HealthyLiving/haemophilus-influenzae-type-b-hib (accessed 24 November 2021).
      6. Australian Government Department of Health. National Immunisation Program Schedule. Available at: https://www.health.gov.au/health-topics/immunisation/immunisation-throughout-life/national-immunisation-program-schedule (accessed 24 November 2021).
      7. NCIRS. Haemophilus influenzae type b (Hib) vaccines for Australian children. Available at: https://ncirs.org.au/sites/default/files/2020-06/Hib%20Fact%20Sheet_1%20July%202020_Final_0.pdf (accessed 24 November 2021).

      MAT-AU-2102458   Date of preparation January 2022

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