Haemophilus influenzae type b (Hib)
If your child has symptoms of Hib infection call triple zero (000) and ask for an ambulance.
Key facts
- Haemophilus influenzae type B (Hib) is a bacteria.
- Hib infection can cause conditions such as meningitis, pneumonia and epiglottitis, which can cause death or long-term complications.
- Hib infection is prevented by vaccination.
- Hib vaccination is recommended for all babies from 2 months of age, and for other people at risk of Hib infection.
- Hib infections can usually be treated with antibiotics.
What is haemophilus influenzae type B?
Haemophilus influenzae type B (Hib) is a contagious bacteria. It can cause serious infections that can affect your:
Hib infection can happen quickly and can be fatal (cause death).
Hib is not the same as influenza B (the flu). Influenza is caused by a virus, not bacteria.
Read more on the difference between bacterial and viral infections.
What are the symptoms of Hib infection?
If you have a baby younger than 3 months old with a fever above 38°C, call triple zero (000) or take them to the nearest hospital emergency department immediately.
Symptoms of Hib infection can appear 2 to 4 days after catching the bacteria. The symptoms depend on which part of your body is affected.
Meningitis
Hib can infect the membranes around the brain and spinal cord. This is called meningitis.
Meningitis can cause symptoms such as:
If your baby has meningitis, they may:
- be drowsy and tired
- have a loss of appetite or not want to feed
- have a high fever and a bulging fontanelle (the soft spot on the top of a baby's head)
Epiglottitis
Hib can infect your epiglottis, which is a small flap of cartilage at the back of the throat. This can cause your epiglottis to become swollen and cause epiglottitis.
Epiglottitis can cause:
- breathing difficulties
- fever
- paleness
- difficulty swallowing
Babies with epiglottitis will dribble a lot and be very unsettled.
Pneumonia
Hib can cause pneumonia, which is an infection in your lungs.
The symptoms of pneumonia include:
- shortness of breath
- fever
- fatigue (tiredness)
- loss of appetite
- headache
- chest pain
- cough
Osteomyelitis and septic arthritis
Hib infection can cause osteomyelitis, which is an infection of your bone. This can cause:
- swelling
- inflammation
- pain over the bone
Hib infection can also cause septic arthritis, which is an infection of the joints.
Cellulitis
Hib can also cause cellulitis, which is an infection of the tissue under the skin.
This can cause areas of skin to become:
- red
- hot
- swollen
- tender
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What causes Hib infection?
Hib bacteria are spread through droplets from your nose or throat that are made by coughing and sneezing. You can catch Hib:
- from contact with an infected person
- by touching something that an infected person has coughed or sneezed on
A person does not need to have symptoms to spread Hib. This is because Hib bacteria can live in the throat of some people without causing symptoms.
When should I see my doctor?
Meningitis, epiglottitis and pneumonia develop quickly and can be fatal if not treated. If you think your child has one of these conditions, take them straight to a hospital emergency department or call triple zero (000) and ask for an ambulance
If you or your child have signs of an Hib infection, visit your doctor. They can diagnose your condition and provide treatment. If you have swelling and pain in a bone or a joint, see your doctor for a diagnosis and treatment plan.
Osteomyelitis and septic arthritis are also dangerous and your child should see a doctor urgently.
FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
How is Hib infection diagnosed?
Your doctor will talk to you about your symptoms and do a physical examination to assess your child's condition.
Hib infection is diagnosed by identifying Hib in body fluids such as blood, sputum and cerebrospinal fluid. Your doctor may do tests such as:
- blood tests and sputum tests
- x-ray
- a lumbar puncture (testing the cerebrospinal fluid that sits around the brain and spinal cord)
How is Hib infection treated?
Treatment depends on the type of Hib infection and your symptoms.
Hib infection is treated with antibiotics. You may also need care in hospital, such as:
- medicine to manage fever or pain
- extra fluids
Can Hib infection be prevented?
If you have had contact with a Hib infected person, a short course of antibiotics may prevent you from catching the disease.
Hib infection can be prevented by vaccination. Before Hib vaccination was added to the National Immunisation Program (NIP) in 1993, Hib was the most common cause of bacterial meningitis in young children in Australia. Hib infections are now rare in Australia.
There are some people at higher risk of Hib infection, such as:
- unvaccinated children under 5 years of age
- Aboriginal and/or Torres Strait Islander children
- people aged over 65 years
- people with weakened immune systems
- people with HIV infection and AIDS
- people with a non-functioning spleen
- people receiving cancer treatments or bone marrow transplant
About the Hib vaccine
Vaccination is your best protection against Hib infection. If you are at risk of Hib infection, ask your doctor to arrange your Hib vaccination.
Details about the Hib vaccine
What age is it recommended?
Vaccination is given at:
- 2 months
- 4 months
- 6 months
- 18 months
How many doses are required?
4
How is it administered?
Injection
Is it free?
It is free for:
- eligible people under 20 years old
- people who have little to no spleen function
- refugees of any age who did not have the vaccine as a child
Common side effects
The vaccine is very safe. Common side effects include redness and swelling where the needle goes in.
A very small number of children (around 1 in 50) have a mild fever that lasts for a short time.
There are several different vaccines available for Hib. You can talk to your doctor about which one is best for you.
You can also ask your doctor if you are eligible for additional free vaccination based on your situation.
How is the spread of Hib prevented?
Hib infection is a nationally notifiable disease. This means your doctor must report cases of Hib infection to your local public health unit. They will try to trace the people you have been in contact with. This helps prevent large outbreaks from occurring.
If your child is diagnosed with an Hib infection, keep them home from childcare or school until they have finished their course of antibiotics.
What are the complications of Hib infection?
Meningitis, epiglottitis and pneumonia caused by Hib infection can cause death. If left untreated, meningitis and epiglottitis are almost always fatal.
Meningitis can also cause long-term brain damage, such as:
Resources and support
For more information on Hib and immunisation in Australia, visit the Department of Health for the:
The Sharing Knowledge About Immunisation website has tools to help you make decisions about immunisation and your family.
To stay on track with your immunisations, the National Immunisation Program (NIP) Schedule shows which vaccines you need and when.
Languages other than English
Health Translations has information about childhood vaccinations in many community languages.
Information for Aboriginal and/or Torres Strait Islander peoples
The Department of Health has specific information on immunisation for Aboriginal and/or Torres Strait Islander people.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: May 2025
