Haemophilus influenzae type b infection
3 May 2024
Causative agent
Haemophilus influenzae type b (Hib) is a bacterium which can cause serious invasive disease especially in young children. Contrary to what the name Haemophilus influenzae suggests, the bacterium does not cause influenza.
Clinical features
Hib infection usually affects children aged below five years. The risk of infection among older children is relatively low. Invasive Hib infection commonly presents with symptoms of infection of membranes covering the brain (meningitis), often accompanied by bacteria 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 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 infected, there may 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
1. Maintain good personal hygiene
- Perform hand hygiene frequently, especially before touching the mouth, nose or eyes; after touching public installations such as handrails or door knobs; or when hands are contaminated by respiratory secretions.
- Wash hands with liquid soap and water, and rub for at least 20 seconds. Then rinse with water and dry with a disposable paper towel or hand dryer. If hand washing facilities are not available, or when hands are not visibly soiled, hand hygiene with 70 to 80% alcohol-based handrub is an effective alternative.
- Cover your nose and mouth with tissue paper when sneezing or coughing. Dispose of soiled tissues into a lidded rubbish bin, then wash hands thoroughly.
- Wear a surgical mask, refrain from work or attending class at school, avoid going to crowded places and seek medical advice promptly if feeling unwell.
- Do not share eating and drinking utensils and wash them thoroughly after use.
- Young children with symptoms of infection should minimise contact with other children.
- Regularly clean and disinfect frequently touched surfaces such as furniture, toys and commonly shared items with 1:99 diluted household bleach (mixing 1 part of 5.25% bleach with 99 parts of water), leave for 15 to 30 minutes, and then rinse with water and keep dry. For metallic surface, disinfect with 70% alcohol.
- Use absorbent disposable towels to wipe away obvious contaminants such as respiratory secretions, and then disinfect the surface and neighbouring areas with 1:49 diluted household bleach (mixing 1 part of 5.25% bleach with 49 parts of water), leave for 15 to 30 minutes and then rinse with water and keep dry. For metallic surface, disinfect with 70% alcohol.
