Haemophilus Influenzae Serotype B

Haemophilus Influenzae Serotype B overview and Definition

The causative agent is haemophilus influenza and it causes life threatening complication. Hamophilus influenzae is a Gram-negative coccobacillus that commonly infects the upper respiratory track of children through the transfer of nasal secretion

Clinical signs & symptoms

The symptoms depends upon the type of illness it causes. These include:


This is an infection of the membranes covering the brain and spinal cord. It can cause fever, headache,stiff neck and vomiting. Very less amount of the population tends to express seizures. They might become very cranky or sleepy. This life threatening disease need the treatment in appropriate manner.


 This severe throat infection can make it hard to swallow or talk. A person might drool and have a very hard time breathing. This too can be life-threatening if not treated right away.



This lung infection can cause fever, coughing and trouble breathing.



This skin infection makes an area of skin red, painful and swollen. It is the bacterial infection that is present beneath the skin surface. Staphylococcus and Streptococcus also hemophilus type B are the two types of bacteria that takes part in the cellulitis. Sometimes the cellulitis develops in the area that has open wounds or at ulceration site.




This joint infection can lead to pain, swelling and redness at the joint. The patient might fell difficulty in walking and doing the normal routine lifestyle.


Ear infections:

These are the common cause of the ear pain.


Sometimes Hib is only found in the bloodstream, where it can travel throughout the body. This is called bacteremia. Children with bacteremia may only have a fever or look very sick. Bacteremia can lead to any of the above illnesses or to sepsis, a dangerous whole-body response to infection. Sepsis can damage many organs or even cause death if not treated right away.



Differential Diagnosis


The bacterial culture is performed on agar plates and preferably the chocolate agar is added with hemin and nicotinamide adenine dinucleotide factors at 37 degree celcius in a CO2  enriched incubator. Blood agar growth is only achieved as a satellite phenomenon around other bacteria. Colonies of H.influenza appears as convex, smooth, pale, grey or transparent colonies.

The cultured organisms shows catalase and oxidase test positive. Serological testing is necessary to  distinguish the capsules polysaccharide and differentiate between H.influenza b and non encapsulated species.

Although highly specific, bacterial culture of H. influenzae lacks sensitivity. Use of antibiotics prior to sample collection greatly reduces the isolation rate by killing the bacteria before identification is possible. Beyond this, H. influenzae is a finicky bacterium to culture, and any modification of culture procedures can greatly reduce isolation rates. Poor quality of laboratories in developing countries has resulted in poor isolation rates of H. influenzae

The bacteria will grow in the hemolytic zone of staphylococcus aureus on blood agar plates. The bacterium will not grow  outside the hemolytic zone of S. aureus due to lack of nutrients. Flides agar is the best for the isolation of the bacteria. In Levinthal medium, the capsulated strains shows distinctive iridescence.

Latex particle agglutination:

The latex particle agglutination test is a more sensitive metho to detect H.influenzae than in culture. Because this method relies on antigen rather than viable bacteria. The antibiotic sensitivity testing is not possible with latex agglutination test alone and hence parallel cultivation of the bacteria is also indicated.

Molecular methods:

Polymerase chain reaction (PCR) assays have been proven to be more sensitive than either LAT or culture tests, and highly specific. However, PCR assays have not yet become routine in clinical settings. Countercurrent immunoelectrophoresis has been shown to be an effective research diagnostic method but has been largely supplanted by PCR.

Chest Xray:

The chest x ray predicts any abnormal area in the lungs

Computed tomography:

It reveals the slice of the lung. It uses both the combination of x ray and computer aided device.

It helps to analyse the size, shape and position of any lung tumour and also it helps in the detection of enlarged lymph nodes.

It also looks for any masses in the adrenal gland, liver, brain and other organs.

 CT guided needle Biopsy:

CT scan might be used to guide a biopsy needle into this  area to get the tissue for lung and further investigations are made.

MRI scan:

It uses the soft tissue image of the organ. It uses the both the magnet and radiowaves and aids in the view of soft tissues of the internal organs.

Immunosorbent assay- detect the  specific IgM or IgG antibodies.


Lumbar puncture or spinal tap:

 The fluid is drawn from the spinal cord and further investigations are made.



The prognosis is excellent with the administration of the proper antibiotics. The mortality rate is only 5%.


The main way to prevent Hib disease is to make sure that kids get the Hib vaccine as infants. This vaccine is very effective  and make the kids to get the vaccine as early as possible.

  • 2 months
  • 4 months
  • 6 months (some vaccine brands don't need the 6-month shot)

They get a booster dose at age 12–15 months.

Children who haven't had the Hib vaccine or didn't get all the shots should stay away from anyone who might have Hib disease until they get all doses.

If your child didn't get the Hib vaccine as a baby, talk to your doctor. Most kids over age 5 won't need the vaccine. But it may be recommended for kids with immune system problems, such as asplenia (a missing or faulty spleen, sickle cell disease and cancer.


Stay away from contaminated areas.

Stay away from the triggering factors

If any surgical correction is indicated do it early

Follow healthy lifestyle

Use a vacuum cleaner fitted with a high efficiency particulate air such as HEPA filter- it can remove more dust than ordinary vacuum cleaners.

Wash the hands properly while coming indoors. It might reduces the infection and also the spread.

Follow healthy diet

Identify potential nesting sites, and clean up debris, clear bushes, and trap rodents to remove them.

Open and air out any rodent-infested spaces that have been shut up for a long time before you enter them.

If you know of an area heavily infested with rodents, contact state or federal health officials about cleaning the area up.







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