Causative agent

Haemophilus influenzae type b (Hib) is a germ which can cause serious invasive disease especially in young children. Contrary to what the name Haemophilus influenzae suggests, the germ does not cause influenza or flu.

Clinical features

Hib infection usually affects children aged below five years. The risk of disease among older children is relatively low. Invasive Hib disease commonly presents as infection of membranes covering the brain (meningitis), often accompanied by germ entering the bloodstream. It may also affect other parts of the body, such as the lungs, upper part of the throat (epiglottis), joints and bones.

The clinical features will depend on the parts of body being affected. When the membranes covering the brain are infected, there will be fever, headache and stiff neck, coupled with decreased appetite, nausea, vomiting, fear of bright light, confusion and sleepiness. When the upper part of the throat is affected, there will be fever, sore throat, drooling, pain on swallowing, refusal to swallow or difficulty in breathing.

If a child has persistent fever, unusual changes in behaviour and deteriorating condition, or in cases of doubt, medical attention should be sought immediately.

Mode of transmission

Hib infection can be spread by contact with nose or throat secretion of an infected person.

Incubation period

The incubation period usually varies from 2 to 4 days, but can be longer.

Management

Prompt antibiotic treatment is necessary for Hib infection. Household members and people having close contact with the patient should be monitored closely for early signs and symptoms of infection. Children younger than 2 years or those with weakened immunity who come into close contact with the patient are at high risk of developing the disease. They should consult the doctor for advice and preventive medication.

Prevention

• Maintain hand hygiene and clean hands properly.
• Wash hands when they are soiled with respiratory secretions e.g. after sneezing or coughing.
• Cover nose and mouth while sneezing or coughing and dispose of nasal discharge and sputum properly.
• Do not share eating and drinking utensils and wash them thoroughly after use.
• Avoid going to crowded places if not feeling well.

2. Effective vaccine against Haemophilus influenzae type b is available. For personal protection, please seek advice from the family doctor.