Haemophilus Influenzae

Haemophilus influenzae type b disease (also known as Hib disease) is a bacterial illness that can cause a potentially fatal brain infection in young children. It is spread through contact with discharges or droplets from the nose or throat of an infected person. The most common and severe manifestation of this disease is meningitis. Immunization with a vaccine starting at two months of age can prevent Hib disease.

What Is Haemophilus Influenzae?

Haemophilus influenzae type b disease (also known as Hib disease) is a bacterial illness that can cause a potentially fatal brain infection in young children. The disease can be treated with antibiotics.

Because of the widespread use of effective vaccines against this illness, very few cases are now diagnosed. In fact, Haemophilus influenzae type b cases have declined by 96 percent over the past 10 years in the United States. However, getting children vaccinated and guaranteeing that they get the complete series of shots is still a challenge, especially among children with poor access to healthcare and in areas of the country with significant under-vaccination.

The disease is spread through contact with discharges or droplets from the nose or throat of an infected person. Immunization with Haemophilus influenzae type b vaccine starting at the age of two months can prevent the disease.

What Causes It?

Haemophilus influenzae type b disease is caused by Haemophilus influenzae serotype b, a bacterium.

Where Does It Live in Humans?

The Haemophilus influenzae type b bacterium is widespread in humans. Along with other bacteria, it usually lives in the throat and nose without causing illness. In some cases, though, the bacterium breaks through the body's defenses and causes disease.

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