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Haemophilus influenzae type b (Hib) is a bacterium that causes serious infections.
Before the advent of effective vaccines, Hib was the most common
cause of bacterial meningitis in children in the United States as well
as in many other countries. Since 1988, when the Hib vaccines were
introduced, the rate of invasive Hib disease has decline by 99% in
infants and young children. When disease occurs, it usually is in
children 2 months to 5 years of age. Hib and types of Haemophilus
influenzae other than type b can cause disease in elderly persons with
underlying health conditions. Hib can cause meningitis (inflammation of
the brain and spinal cord covering) and other infections such as
pneumonia (lung infection), ear, skin, joint, and blood infections.
Hib is spread from person-to-person by airborne droplets and direct contact with infected respiratory secretions.
Hib is carried in the nose or throat of children and adults who are
infected. It is possible for people who are not ill to carry Hib and
spread it to others. It is then spread to the next person through
contact with discharge or droplets from the nose or mouth.
Symptoms to look for include:
The time period between when someone is exposed to Hib and when symptoms develop is unknown, but may be as short as 2 to 4 days.
Laboratory testing is available to confirm a Hib infection.
People who think they may have Hib disease should see a doctor or
their local health department. Hib disease is diagnosed by testing the
blood, spinal fluid, middle ear, and other bodily fluids. See a doctor
immediately for treatment.
Treatment with antibiotics should be started immediately to stop the infection from causing serious complications or death.
Certain people in close contact with someone who has Hib disease should receive treatment as well. In
specific situations, such as childcare settings, people who have been
exposed to someone with Hib may be given a drug called rifampin to
prevent getting or spreading Hib. Rifampin is not recommended for
pregnant women. High risk contacts include:
Hib disease can be prevented with Hib vaccine.
Hib vaccine is recommended for all children starting at 2, 4, 6 and
15 months of age. Hib vaccine is recommended for all children under 5
years of age who have not been previously immunized, and others may need
Hib vaccine if they are at an increased risk for disease. Age
appropriate vaccination against Hib is required for entry into Maryland
childcare institutions and schools. For additional information about Hib
vaccine, please visit: http://www.cdc.gov/vaccines/vpd-vac/hib/default.htm.
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