Influenza ( French grippe) is an acute infectious disease of the respiratory tract caused by the influenza virus . Included in the group of acute respiratory viral infections ( ARVI ). Periodically spreads in the form of epidemics and pandemics . In nature, there are three genera of influenza viruses - A, B and C. Each of these genera has subtypes (serotypes), which differ in the set of antigens (neuraminidase (N) and hemagglutinin (H)). The development of seasonal epidemics is usually associated with the circulation of type A viruses among the population, since they are highly variable (prone to mutation). Types B and C are more stable, therefore, having encountered them once, a person receives lasting immunity, which reduces the likelihood of getting sick again. Influenza is infected by airborne droplets; the source of infection is a sick person, who, when coughing, creates a dangerous infection zone with a radius of about 2 meters. It is also important to remember that the patient becomes contagious even before the first symptoms of the disease appear (such a latent period of illness can last a day) and remains so for several more days after the body temperature normalizes. Therefore, you must always be vigilant, even if there are no clearly sick people nearby.

Seasonal influenza epidemics in Kazakhstan usually begin in November. This happens almost every year, because the pathogens of the disease are constantly changing, and the population has no immunity to them . WHO specialists, having observed the circulation of influenza viruses for decades, can predict with a high probability which of them will cause an epidemic this year. The influenza immunoprophylaxis system is built on this (a new vaccine is created every year for specific serotypes of viruses).

For example, for the 2015-2018 season, according to WHO, the following viruses will be relevant for the northern hemisphere: a virus similar to A/California/7/2009 ( H1N1 ) pdm09; A/Switzerland/9715293/2013 (H3N2)-like virus; B/Phuket/3073/2013-like virus (Yamagata lineage).

The influenza virus is characterized by the following symptoms: fever, chills, aches in the back, limbs, headache and eye pain, catarrhal symptoms - runny nose , feeling of “stuffiness” in the nasopharynx, sore throat, cough (dry at first).

The flu itself is not dangerous, but its complications pose a danger to the lives of patients: tracheitis, bronchitis , pneumonia , otitis , sinusitis (inflammation of the ears and sinuses, respectively), myocarditis (damage to the heart muscle), meningitis (inflammation of the pia mater) , myositis (inflammation of skeletal muscles), glomerulonephritis (kidney damage), organ failure (respiratory, cardiac, renal ). Among acute respiratory viral infections, influenza is the only disease for the treatment of which specific antiviral agents have been created . These include: Oseltamivir (Tamiflu), Rimantadine (according to WHO, it is less effective against “modern” influenza viruses).

To avoid getting the flu, you need to act in two directions:

1) Prevent infection - if possible, avoid crowded places during an epidemic, do not contact sick people, wash your hands more often, ventilate rooms well, regularly carry out wet cleaning, disinfect door handles, toys, etc.

2) Increase the body’s resistance to influenza viruses (strengthen local immunity: humidify the air in the room, use herbal immunomodulators, stimulators of interferon production, vitamin complexes, homeopathic preparations, create specific protection - by getting a flu vaccine .

Among all the listed preventive measures, the most effective are, of course, the flu shot and the correct behavior model. Even the most modern medicines will not help prevent the development of the disease if a person does not adhere to an optimal lifestyle from an epidemiological point of view during an influenza epidemic: walk more than take public transport, wash and disinfect hands more often, ventilate rooms in which lives and works, keeps the house clean, etc.

Makusheva A.E., Berdieva B.S.

virology laboratory doctors

NCE branch in Astana