The immunologist spoke about the risks of the "Hong Kong" flu.

An increase in the incidence of the influenza A(H3N2) strain has been recorded in the current season, causing concern among doctors due to its high variability and the risks of severe complications. On December 4, Izvestia was informed by an allergist, immunologist, rheumatologist and general practitioner of the NCC NCC No. 2 of the Russian National Research Medical University. Academician of B.V. Petrovsky" Elena Sycheva.

"The increase in the incidence of influenza A(H3N2) is indeed causing serious concern in the professional community. About the dominance of strain A(H3N2) ("Hong Kong flu") and its features, Strain A(H3N2) is not completely new, but is characterized by high variability (antigenic drift)," Sycheva emphasized.

She noted that the strain is traditionally highly contagious and capable of provoking severe forms of the disease, especially in groups and among vulnerable groups of the population. Compared to influenza B, A(H3N2) causes larger epidemics, and in relation to A(H1N1), pdm09 often leads to complications in elderly patients.

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The doctor stressed that people over 65 years of age, patients with chronic diseases, children under 5 years of age, pregnant women and people with immunodeficiency remain the most vulnerable. According to her, the most common complications are viral and bacterial pneumonia, acute respiratory distress syndrome, asthma and COPD exacerbations, as well as myocarditis and decompensation of heart failure.

She clarified that sinusitis, otitis media and neurological consequences are additionally possible. The expert paid special attention to prevention. The expert noted that seasonal vaccines from 2024-2025 contain topical antigens, including A(H3N2), and remain a key protective tool.

"The vaccine does not guarantee 100% protection against the disease, but it is extremely effective in preventing severe forms, complications and deaths, especially in high-risk groups. The optimal time for vaccination has already passed, but it's not too late to get vaccinated, since the peak of the epidemic often falls in January-February," Sycheva said.

The specialist recommended paying attention to non-specific prevention: use masks in crowded places, maintain hand hygiene, limit contact with the sick and regularly ventilate the premises. She pointed out that with a sharp increase in temperature, severe headache and typical symptoms, it is important to consult a doctor immediately, avoiding self-medication and especially taking antibiotics without indications.

"The situation requires increased attention from both medical professionals and the public. Timely prevention and early access to qualified help is the key to reducing the negative effects of the circulation of this aggressive strain," concluded Sycheva.

The Reuters news agency, citing the director of the Center for Respiratory Tract Infections at the Pasteur Institute in France, Marie-Anne Ramey-Welty, reported on November 27 that a mutation of the avian influenza virus could allegedly lead to a larger pandemic than COVID-19 if the pathogen could be transmitted between humans. At the same time, it was noted that at the moment the world is better prepared for such a threat due to the availability of ready-made vaccine options and established methods.

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