NJDHSS, Communicable Diseases, Disease Fact Sheets: Hemophilus influenzae Type B Meningitis

What You Should Know About. . .

Haemophilus influenzae type B Meningitis

What is Haemophilus influenzae type B meningitis?

Haemophilus influenzae type B meningitis is an infection of the tissue which covers the brain (meninges) caused by the bacteria Haemophilus influenzae. In addition to meningitis, this bacterium can also cause blood stream infections (sepsis), pneumonia, joint and bone infections and other infections. There are six different serotypes of Haemophilus influenzae, but type B causes most of the illness caused by this bacterium.

Who gets Haemophilus influenzae type B meningitis?

Haemophilus influenzae type B disease almost exclusively affects children under 5 years of age, and prior to the introduction of the Hib (Haemophilus influenzae type B) vaccine, it was the most common cause of bacterial meningitis in this age group.

How is Haemophilus influenzae type B meningitis spread?

Haemophilus influenzae type B bacteria are spread from person to person by direct contact, or through inhalation of respiratory droplets released into the air through sneezing or coughing.

What are the symptoms of Haemophilus influenzae type B meningitis?

The most prominent symptom of Haemophilus influenzae type B meningitis in older children is a stiff neck. In infants, there may be a bulging fontanelle. These symptoms are usually preceded by other symptoms including fever, nausea, vomiting, headache and irritability. The illness may progress rapidly, and in most cases, it requires hospitalization.

How soon do symptoms occur?

Symptoms usually occur within 2 to 4 days after inhaling Haemophilus influenzae type B bacteria.

How can I tell if my child has Haemophilus influenzae type B meningitis?

Early Haemophilus influenzae type B meningitis may indeed look similar to a "bad cold". A parent should watch for changes that suggest the illness is becoming more severe than what the child has typically experienced in the past. A fever that can't be controlled, abnormal and unusual changes in the child's behavior, symptoms the child has never had before - all should prompt an immediate call to the child's physician or a visit to a hospital emergency department. A very ill child should be watched closely, as changes can happen quickly. Parents should never hesitate to call their child's physician if they are uncomfortable about their child's condition.

How is Haemophilus influenzae type B meningitis diagnosed?

Haemophilus influenzae type B infection can be diagnosed by examination of the CSF (cerebrospinal fluid, the fluid which surrounds the brain) and/or the blood.

Can Haemophilus influenzae type B meningitis be treated?

Yes, Haemophilus influenzae type B meningitis can be successfully treated with antibiotics, and most patients do recover completely. The earlier treatment is begun, the more successful it is, thus it is important that the diagnosis be made as early as possible.

How long is an infected person infectious to others?

An infected individual is no longer infectious to others after 1 to 2 days of appropriate antibiotic therapy.

Can Haemophilus influenzae type B meningitis be prevented after exposure?

There is a preventive therapy which is recommended to specific individuals under specific circumstances. Individuals who have had close personal contact with someone who has become ill with Haemophilus influenzae type B meningitis are recommended to take a preventive antibiotic. This antibiotic is necessary only for those individuals who have had recent close personal contact, such as sharing living space, kissing, sharing food and eating utensils or other contact with oral secretions. It is generally not necessary for individuals who have shared only office space or classroom space. The physician caring for the patient hospitalized with Haemophilus influenzae type B meningitis, or a representative from the health department interviews the patient, determines who should be contacted regarding preventive antibiotic therapy, and ensures that these individuals are notified.

Is there a vaccine to prevent Haemophilus influenzae type B meningitis?

Yes. The Hib (Haemophilus influenzae type B) vaccine should be given to all children less than 5 years of age. Under ideal circumstances, the first dose should be given at 2 months of age. The vaccine requires 3 or 4 doses to be given, depending upon which of several brands of vaccine is used.