— What does today’s picture of flu cases in Russia look like?
— Generally, the situation is steady. There is a seasonal uptick in ARVI infections, but nothing alarming. Flu cases remain few so far this season.
— Were there more flu cases last year?
– On the whole, yes. In mid-November 2022, flu activity spiked rapidly. It remains unpredictable how this season will unfold.
— Has the coronavirus that fueled the pandemic changed the normal circulation of viruses?
– Yes. Before COVID-19, viral patterns followed familiar cycles with predictable trends. SARS-CoV-2 altered these dynamics. In the first year of the pandemic there were hardly any flu cases. In the second year, flu returned, boosting numbers, but Omicron intervened. Last year, flu activity surged again with many hospitalizations.
— It isn’t clear yet how this year will compare to last or to pre-pandemic times. Yet, looking at the Southern Hemisphere suggests a return to the pre-pandemic pattern, with ARVI pathogens circulating as usual and COVID-19 present alongside them.
— To anticipate this season, would you look to Australia or South America for clues?
– Both regions are informative. The focus remains on temperate climate zones. South Africa is also monitored. So far, Southern Hemisphere data show no unusual spikes; flu generally circulated as expected, with no single strain showing extraordinary potential for a sharper threat.
— How are the circulating viruses selected for vaccines? How are vaccine strains decided?
— The institute maintains continuous surveillance of ARVI pathogens year-round. More than 140 centers worldwide participate in the WHO global influenza surveillance network. They collect morbidity data and isolate viruses from patients to identify circulating variants. With this, WHO experts determine which strains should be included in vaccines. The recommendations are issued in February so manufacturers can prepare vaccines for autumn deployment. (WHO sources)
— How many types are considered?
– Dozens are reviewed. The aim is to identify the dominant variants likely to circulate in the coming season. Like horse races, several variants exist, each with unique characteristics. The WHO expert group then names the dominant strains for inclusion in vaccines. (WHO guidance)
— Are influenza viruses also collected in Russia? How many are in the database for this season?
— Yes, sampling is ongoing. Numbers are small yet, but new cases appear weekly. Based on last year, influenza A(H3N2) is expected to dominate. Importantly, this year’s vaccines include protection against H3N2.
— How is the flu vaccine administered? We have Sovigripp, Ultrix, Grippol, Flu-M. Which will be used? Some vaccines are trivalent, others quadrivalent.
— The vaccines differ in how many strains they cover. This year, the situation is unusual: there is no practical difference between trivalent and quadrivalent vaccines because the Yamagata lineage influenza B virus largely disappeared during the pandemic. Both vaccine types are effective for the season. (Vaccine lineage history)
— A COVID-19 vaccine based on the influenza virus has been developed at the institute. What is its status?
— It is a vector vaccine. Phase II trials have completed. Results show safety and immunogenicity, and regulators are being prepared with a full report. The third phase will test effectiveness in a larger group of volunteers.
— Will the flu virus in this vaccine change every year?
— Yes, annual updates are expected. An added benefit is protection against both flu and COVID-19. (Vaccine update)
— Which coronavirus component is used to trigger an immune response?
— The N-protein is used as the target.
— Do you only make vector vaccines, or is mRNA work also pursued?
— Both vaccine platforms are pursued. mRNA vaccines offer advantages, and if trials succeed, they could quickly adapt to changing flu strains. Long-term safety remains under study. A flu-focused drug based on mRNA technology is also in development, aiming to harness antibodies against the influenza virus. (Research notes)
— People have talked about a universal flu vaccine. How feasible is that given constant viral mutation?
— A universal vaccine is the focus of many centers, but no definitive solution exists yet. Some candidates reached early trials and failed, while others showed promise. Ongoing research targets the most conserved parts of the virus to elicit lasting protection. The goal is a vaccine effective for several years. (Clinical trial updates)
— WHO has raised attention to RSV, a virus causing serious disease in children and the elderly. Is the institute involved in RSV surveillance?
— Yes, the global RSV surveillance framework includes the institute. Since 2017, WHO has piloted RSV monitoring in multiple regions, highlighting the central role of national influenza centers in coordinating respiratory virus surveillance. (WHO RSV program overview)
— How many surveillance programs does WHO run for respiratory pathogens?
— The priority focuses on influenza, RSV, and SARS-CoV-2, with a broad network coordinating data and responses. (WHO program summary)
— Why does RSV draw so much attention?
— RSV remains a serious risk for young children and older adults. At the start of flu season in the United States last year, RSV and COVID-19 activity surged together in what experts called a tridemic. That pattern underscores the need for vigilant monitoring and prevention. (Public health briefing)
— What prevention options exist today for RSV?
— Two main strategies are used: vaccination and monoclonal antibody treatment. Monoclonal antibodies are targeted for times of higher risk, especially in young children. This year two RSV vaccines were approved: one administered to pregnant people near delivery to protect the newborn, and another for the elderly. The institute is developing an RSV vaccine for the elderly using an influenza virus vector for intranasal use, with Phase I results showing promise and a Phase II trial planned later this year. (RSV vaccine program)
— Is intranasal vaccination really about flu and RSV protection?
— Yes. Nasal vaccination aims to provide protection at the site where infections enter, offering broader immunity across the season. It is viewed as a practical approach to curb multiple respiratory infections. (Immunology perspective)
— Is a triple vaccine for flu, RSV, and COVID-19 feasible?
— Combination vaccines are being explored and could emerge when there is enough demand and scientific backing. (Vaccine development briefings)