Hib meningitis

Hib meningitis is a life-threatening infectious disease that causes inflammation of the layers that surround the brain and spinal cord. These layers are called the meninges – they help to protect the brain from injury and infection.

How is Hib meningitis caused?

When the Hib bacteria invade, they can overcome the body’s defences and lead to infection. The bacteria can travel in the bloodstream to infect the meninges, causing meningitis, or whilst in the bloodstream they can cause septicaemia.

When the bacteria infect the meninges, the blood vessels in the lining of the brain are damaged. This allows the bacteria to break through and infect the cerebrospinal fluid (CSF) and the meninges become inflamed and pressure around the brain can cause nerve damage. Pressure on the brain can produce the specific symptoms associated with meningitis.

As the bacteria multiply rapidly in the bloodstream, they begin to release poisons from their outer coating. The body’s natural defences have little effect on these poisons and eventually blood vessels become damaged. This results in the more specific symptoms of septicaemia.

Hib bacteria can also cause other infections such as epiglotittis (rapid swelling of the epiglottis), septic arthritis, osteomyelitis, pericarditis, cellulitis, bronchitis and otitis media.

How is Hib meningitis treated?

Hib meningitis requires rapid admission to hospital and treatment with antibiotics. For more information, visit our section on treatment of meningitis.

Who gets Hib meningitis and why?

A routine Hib vaccine was introduced to the UK in 1992 and forms part of the Childhood Vaccine Programme. The vaccine has been hugely successful. Before 1992 there were around 900 cases of Hib meningitis in the UK, with the majority of cases occurring in the under 4s. This number has been reduced by 98% preventing thousands of cases and hundreds of deaths. The Hib bacteria are now carried by less than 1% of the population.

Key facts

A routine vaccine is available to prevent Hib disease.
Each year there are around 30 cases of Hib meningitis in the UK.
Most people make a good recovery, but around 3% will die.
3 – 5% of survivors will suffer severe after-effects, such as deafness and long-term neurological complications.