Haemophilus influenzae

A hemophilic infection is a group of acute infectious diseases caused by the bacterium Haemophilus influenzae type b, affecting mainly children and characterized, the central nervous system with the possible formation of purulent foci in various tissues and organs (sepsis).

Hemophilic infection is especially dangerous for young children because it is transmitted by airborne droplets and contact (through toys and other objects that children take into the mouth) and the carrier can proceed without showing any symptoms. The result of this infection can be various complications in the course of common colds, some of which (meningitis, epiglottitis) can be fatal.

This disease is a component of the microflora of the nasopharynx. The most dangerous type b occurs in 5-25%, but according to studies, in kindergartens, the proportion of carriers can reach 40%, which causes frequent colds.

This disease is surrounded by a special capsule, which makes the bacterium invisible to lymphocytes, which several times reduces the body’s ability to develop immunity to hemophilic infection, depriving the body of the ability to form long-term immunity. In children under five years of age, it is impossible to develop enough antibodies to protect them.

About 3 million cases of hemophilic infection are registered in the world every year, of which about 400-500 thousand are fatal.

Acute infectious diseases caused by influenza bacillus are characterized by a predominant lesion of the respiratory system, the central nervous system, and the development of purulent foci in various organs.

Airborne droplets transmit the infection from a sick person or a carrier of the infection.

What are the main clinical signs? A local inflammatory process of the mucous membrane of the respiratory tract may develop or hematogenous (carried with the blood flow) causes diseases to develop. Haemophilus influenzae type B is one of the most common causes of generalized infection (bacteremia) in children; half of them develop purulent meningitis, quite often (15–20%) pneumonia, and less often other focal lesions. As a rule, hemophilic infection is acute, but some clinical forms can take a long course. Hemophilic infection can occur in the following clinical forms:

• Purulent meningitis
• Acute pneumonia
• Septicemia (blood poisoning)
• Inflammation of the subcutaneous tissue
• Epiglottitis (inflammation of the epiglottis causes airway obstruction)
• Purulent arthritis
• Other diseases (pericarditis, sinusitis, otitis media, respiratory diseases, etc.)

Complications after Haemophilus influenzae

There are several risk groups for this disease. First, children are most often affected by this infection. Children 6-12 months of age who are bottle-fed and do not receive small additional amounts of maternal antibodies in breast milk are especially at risk of developing the most severe forms of pneumonia and meningitis infection. For this reason, artificial feeding is an additional indication for vaccination against Haemophilus influenzae infection, starting from 3 months of age.

People of extreme ages (children under two years of age, the elderly) and people with low socioeconomic status are also susceptible to hemophilic infection. In addition, persons with low socioeconomic status, extremely weak and suffering from alcoholism, and patients with lymphogranulomatosis (Hodgkin’s disease) or sickle-cell anemia are susceptible to the disease. Persons who have undergone splenectomy (removal of the spleen) are also at risk.

The incidence rises in late winter and spring.

Haemophilus influenzae symptoms. The duration of the incubation period is difficult to establish since the disease is often a consequence of the transition of latent infection to a manifest one. Both a local inflammatory process of the mucous membrane of the upper respiratory tract and diseases caused by hematogenous dissemination can develop.

Haemophilus influenzae often occurs in children as a common respiratory infection with associated symptoms. However, cases of more severe forms of infection are not uncommon. The most severe form of hemophilic infection is purulent meningitis. Hemophilic meningitis is difficult to treat because the pathogen produces enzymes that make it resistant to antibiotics. Therefore, the treatment results are not always successful, and mortality in severe forms of the disease can reach 16–20%. Be sure to see your doctor and have a physical examination if you notice some hemophilus influenzae infection symptoms.

A third of patients who have had hemophilic meningitis develop irreversible neurological complications of convulsions, delayed neuropsychic development, deafness, blindness, etc.

• Pneumonia caused by this disease type b occurs mainly in children from 2 to 8 years old. Its course in 60% of cases also has various complications, including from the heart and lungs.
• Up to half of all purulent infections of the ear, throat, and nose are associated with hemophilic infection, particularly recurrent purulent otitis media (inflammation of the middle ear) and sinusitis (inflammation of the paranasal sinuses).
• Hemophilic sepsis often develops in children 6-12 months of age, predisposed to this disease. It proceeds violently, often as lightning-fast, with septic shock and rapid death of the patient.
• Purulent arthritis is a consequence of hematogenous drift of this disease often accompanied by osteomyelitis.

Why is the disease dangerous? Purulent meningitis is observed mainly in children from 9 months of age up to 4 years.

The disease begins acutely, sometimes with acute respiratory infections, then rapidly develops clinical symptoms characteristic of bacterial meningitis. Sometimes meningeal syndrome is combined with other manifestations of hemophilic infection (purulent arthritis, inflammation of the epiglottis, cellulitis- inflammation of the subcutaneous fat). The disease is difficult and often fatal (about 10%).

Hemophilic pneumonia can manifest itself both in the form of focal and in the form of lobar (lobar), very often (up to 70%) accompanied by purulent pleurisy (in children), which may be complicated by purulent pericarditis, inflammation of the middle ear.

Hemophilic sepsis develops more often in children 6–12 months of age predisposed to this disease. It proceeds violently, often as lightning-fast, with septic shock and rapid death of the patient. Inflammation of the subcutaneous tissue (cellulite) also develops in children under 12 months old, more often localized on the face. It often begins with a picture of acute respiratory infections (rhinopharyngitis), then swelling appears in the cheek area or around the orbit. The skin over the swelling is hyperemic with a cyanotic tinge; sometimes the disease is accompanied by inflammation of the middle ear.

Purulent arthritis is a consequence of hematogenous drift of This disease, often accompanied by osteomyelitis.

If your child suspects a hemophilic infection, you should urgently see a doctor and undergo a physical examination.

Hemophilic infection treatment

Haemophilus infections are difficult to treat because this disease has a record of antibiotic resistance. Penicillin antibiotics, erythromycin, chloramphenicol, tetracycline- the percentage of Haemophilus influenzae resistance to them is 80-100% (of the number of isolated bacterial samples). For this reason, even timely treatment with modern antibiotics is often ineffective. Without etiotropic therapy, some forms of hemophilic infection (meningitis, epiglottitis) almost always end in the patient’s death. It is necessary to start treatment for hemophilic infection as early as possible.

Currently, the only way to prevent this infection is through vaccination. According to WHO recommendations, vaccination against the hemophilic disease is indicated for all children. Vaccination efficiency is now estimated at 95-100%.

Modern vaccines are chemically bound antigens of this disease capsule and tetanus toxoid, which is needed for the main antigen to develop immunity in children under 18 months.

Recommended calendars. WHO recommends any one of the following vaccination schedules for this disease infection:

• 3 doses as part of the primary vaccination course without a booster dose (3p + 0)
• 2 doses as part of the primary vaccination course and a booster dose (2p + 1)
• 3 doses as part of the primary vaccination course and a booster dose (3p + 1).

In countries where the burden of severe Haemophilus influenza B infection is peaking in young infants, giving three doses of vaccine at an early age may be beneficial.