Overview

Haemophilus influenzae (H. influenzae) is a group of bacteria that can cause different types of infections in babies and children. H. influenzae most often cause ear, eye, or sinus infections. They also cause pneumonia.

A more serious strain of the bacteria called H. influenzae type b is no longer active in the U.S. because of a vaccine. The type b strain caused many cases of infection of the membranes that surround the brain (meningitis). It also caused cases of a life-threatening infection called epiglottitis. This is infection of the area of the throat that covers and protects the voice box and trachea during swallowing. In rare cases, a child may still develop an H. influenzae type b infection. This can occur in a child who has not finished his or her series of vaccines. Or it can occur in an older child who did not get the vaccine as a baby. Children who travel to other countries may also be at risk because, worldwide, not all children get the vaccine for H. influenzae type b.

Causes

The H. influenzae bacteria live in the nose, sinuses, and throat. They are usually spread by close contact with an infected person. Droplets in the air from a sneeze or cough can be inhaled and may also cause infection.

Symptoms

Symptoms can occur a bit differently in each child. Below are the most common symptoms.

Middle ear infection (otitis media)

This may develop after a child has a common cold caused by a virus. Symptoms may include:

  • Unusual irritability
  • Trouble sleeping or staying asleep
  • Tugging or pulling at one or both ears
  • Fever
  • Fluid draining from an ear or ears
  • Loss of balance
  • Hearing problems
  • Ear pain
  • Loss of appetite

Conjunctivitis

This is an inflammation of the conjunctiva of the eye. The conjunctiva is the membrane that lines the inside of the eyelid and also a thin membrane that covers the eyeball. Symptoms may include:

  • Eye redness
  • Swelling
  • Fluid from one or both eyes
  • Burning feeling of the eyes
  • Eyes sensitive to light (photophobia)

Sinusitis

This is infection of the sinuses. Symptoms in younger children may include:

  • Runny nose that lasts longer than 10 to 14 days. Nasal fluid may become thick green, yellow, or blood-tinged.
  • Nighttime cough
  • Occasional daytime cough
  • Swelling around the eyes

Symptoms of sinusitis in older children may include:

  • Runny nose or cold symptoms that last longer than 10 to 14 days
  • Nasal fluid that drains down the back of the throat (postnasal drip)
  • Headache
  • Pain over the cheek bones or over the eyes that’s worse when leaning over (sinus pain)
  • Bad breath
  • Cough
  • Fever
  • Sore throat
  • Swelling around the eye that’s worse in the morning

Epiglottitis

This is an infection of the area of the throat that covers and protects the voice box and windpipe (trachea) when swallowing. Epiglottitis is a medical emergency. It can be fatal if not treated rapidly. Because of the H. influenzae type b vaccine, epiglottitis is very rare in children and babies.

Symptoms may include:

  • Quick onset of a very sore throat
  • Fever
  • Muffled voice
  • No cough
  • Shortness of breath

As the infection gets worse, symptoms may include:

  • Drooling
  • Inability to talk
  • Leaning forward while sitting
  • Breathing with mouth open
  • Trouble breathing

Meningitis

This is an infection of the membranes that surround the brain and spinal cord. Because of the vaccine, meningitis caused by H. influenzae is very rare in children and babies. Symptoms in children older than 1 year may include:

  • Neck or back pain, especially when moving the chin toward the chest
  • Headache
  • Nausea and vomiting
  • Neck stiffness

In babies, symptoms are more general and may include:

  • Irritability
  • Sleeping all the time
  • Refusing a bottle
  • Crying when picked up or being held
  • Crying that won’t stop
  • Bulging soft spot (fontanelle)
  • Behavior changes
  • Fever
  • Not bending his or her neck when moving or playing with a toy

The symptoms of H. influenzae can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.

Diagnosis

The healthcare provider will ask about your child’s symptoms and health history. He or she will give your child a physical exam. Your child may also have tests, such as:

  • Testing of a small sample of fluid from the eye, ear, blood, or spinal canal to check for signs of the virus
  • Blood tests to check for signs of the virus
  • Chest or neck X-ray

Treatment

Antibiotics are used to treat infections caused by H. influenzae. The length of treatment varies depending on where the infection is and how serious it is. Other treatment is done to ease symptoms. Talk with your child’s healthcare provider about the risks, benefits, and possible side effects of all medicines.

Prevention

Vaccines against H. influenzae type b are routinely given in a 3- or 4-part series. The vaccine is often called the "Hib" vaccine. The first doses are given at ages 2 and 4 months or at ages 2 months, 4 months, and 6 months. A booster is then given between 12 and 15 months of age. If a child has not had the vaccine and is older than 5 years, he or she may not be vaccinated. Older children should also have the vaccine if they:   

  • Have sickle cell disease
  • Don’t have a spleen
  • Have a weak immune system
  • Have HIV

When to Call a Healthcare Provider

Call the healthcare provider if your child has:

  • Symptoms that don’t get better, or get worse
  • New symptoms

Key Points

  • Haemophilus influenzae (H. influenzae) is a group of bacteria that can cause different types of infections in babies and children.
  • H. influenzae most often cause ear, eye, or sinus infections. They also cause pneumonia.
  • A more serious strain of the bacteria called H. influenzae type b is no longer active in the U.S. because of a vaccine.
  • The H. influenzae bacteria are usually spread by close contact with an infected person. Droplets in the air from a sneeze or cough can be inhaled and may also cause infection.
  • Antibiotics are used to treat infections caused by H. influenza.
  • Vaccines against H. influenzae type b are routinely given in children.

Next Steps

Tips to help you get the most from a visit to your child’s healthcare provider:

  • Know the reason for the visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.
  • Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
  • Ask if your child’s condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if your child does not take the medicine or have the test or procedure.
  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.