Haemophilus influenzae Type B (Hib disease, Haemophilus b)
What is Haemophilus influenzae type b (Hib) disease?
Haemophilus influenzae is a type of bacteria that is commonly found in the nose and throat of children and adults. A particular type, Haemophilus influenzae serotype b (Hib), can invade and cause serious infections. Hib may cause meningitis (inflammation of the coverings of the spinal column and brain), bloodstream infections, pneumonia, arthritis, and infections in other parts of the body. Despite its name, this disease has nothing to do with the influenza (flu) virus.
Who gets Hib disease?
Hib disease can occur at any age. Although Hib was once the leading cause of bacterial meningitis among young children, few childhood cases are reported now due to widespread use of Hib vaccination. Hib disease is more commonly seen in unimmunized or incompletely immunized children, especially those less than 5 years of age, and in people with weakened immune systems.
What are the symptoms of Hib disease?
Symptoms of meningitis may include fever, headache, vomiting, nausea, listlessness, and a stiff neck or back. Pneumonia symptoms may include shortness of breath, fever, lack of energy, chest pain, and cough. Other symptoms depend upon the part of body infected.
How soon after exposure do symptoms appear?
Symptoms generally appear in less than 10 days after exposure and more commonly within 2-4 days.
How is Hib disease spread?
Hib disease may be transmitted through contact with mucus or droplets from the nose and throat of an infected person often by coughing or sneezing. Hib also is spread by people who have the bacteria in their noses and throats but are not ill (asymptomatic).
How long can an infected person carry Hib disease?
The contagious period varies and, unless treated, may last as long as the organism is in the nose and throat, even after symptoms disappear. A person can no longer spread Hib disease after taking the proper antibiotics for 1-2 days.
What is the treatment for Hib disease?
Specific antibiotics generally are used to treat serious infections.
How can Hib disease be prevented?
Hib vaccinations are available. All children should be immunized against Hib disease beginning at approximately 2 months of age. Multiple doses usually are needed to ensure protection. Some older children and adults with weakened immune systems are at increased risk for infection and should be immunized if they were not immunized in childhood. Contact your physician or local health department for further information about vaccination.
How can I get more information about Hib disease?
- If you have concerns about Hib disease, contact your healthcare provider.
- Call your local health department. A directory of local health departments is located at
- Visit the Centers for Disease Control and Prevention website at