Russian health expert warns of new flu strains with no existing immunity
In short
The director of the Health Ministry’s Smorodintsev Influenza Research Institute, Dmitry Lioznov, said new flu strains are circulating in Russia to which the population has no immunity, after all three components of this season’s vaccines were changed. He urged vaccination, especially for children, pregnant women, the elderly and people with chronic illnesses. Kommersant reported the flu situation in the country is currently stable and that domestic producers fully cover vaccine demand, while Vedomosti cited Rospotrebnadzor data showing 727,000 cases of acute respiratory infections and flu in week 39 of 2026, with 98.9% of identified pathogens non-influenza.
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A Health Ministry expert said new flu strains are circulating in Russia to which the population has no immunity. Dmitry Lioznov, director of the Smorodintsev Influenza Research Institute of the Russian Health Ministry, said all three components of this season’s flu vaccines had been changed, which he said showed the arrival of new flu viruses “to which we have no immunity,” according to Kommersant and Vedomosti. RIA Novosti, an official outlet, reported the same warning in headline form. [ 1 , 2 , 3 ]
Lioznov called for vaccination, especially among vulnerable groups: children, pregnant women, the elderly and people with chronic illnesses. He said immunity takes at least two weeks to form, so vaccination should be planned in advance, Kommersant reported. He also said the flu situation in the country is currently stable, and that Russian manufacturers fully cover the country’s need for flu vaccines, with domestic preparations used for preventive shots for five years already. [ 2 ]
Kommersant reported that the vaccine composition is updated on the recommendation of the World Health Organization because viruses change constantly and the previous year’s vaccine may work less well against new variants. This season’s components were designed to protect against swine flu, Hong Kong flu and influenza B, the outlet reported, adding that the change does not guarantee protection against infection but removes the mismatch between the old components and the new virus variants. [ 2 ]
Vedomosti, citing Lioznov’s quote as reported by RIA Novosti, added data it attributed to Rospotrebnadzor: 727,000 cases of acute respiratory viral infections and flu were registered in Russia in week 39 of 2026, a figure dated to a September 29 statement. The agency said seasonal illness was developing in line with forecasts, and virological monitoring showed 98.9% of identified pathogens were non-influenza viruses, with swine flu, Hong Kong flu and types B and C accounting for up to 1.1%. [ 3 ]
Why it matters
The warning comes at the start of the seasonal vaccination window, and officials say protection takes at least two weeks to develop, so timing affects how many people are covered before circulation picks up. Vedomosti’s citation of weekly surveillance data indicates the reported new strains account for only a small share of current respiratory infections, suggesting the practical impact this season is still uncertain.
Key facts
- Dmitry Lioznov, director of the Smorodintsev Influenza Research Institute of the Russian Health Ministry, said new flu strains are circulating in Russia to which Russians have no immunity. [ 1 , 2 , 3 ]
- All three components of this season’s flu vaccines were changed, which Lioznov said indicates the arrival of new strains. [ 2 , 3 ]
- Lioznov called for vaccination of vulnerable groups: children, pregnant women, the elderly and people with chronic diseases. [ 2 , 3 ]
- According to Lioznov, immunity takes at least two weeks to form, so vaccination should be planned in advance. [ 2 ]
- Lioznov said the flu situation in the country is currently stable, and Kommersant reported that Russian manufacturers fully meet the country’s need for flu vaccines. [ 2 ]
- The vaccine components this season target swine flu, Hong Kong flu and influenza B, Kommersant reported. [ 2 ]
- Vedomosti cited Rospotrebnadzor as saying 727,000 cases of acute respiratory viral infections and flu were registered in Russia in week 39 of 2026. [ 3 ]
- According to virological monitoring cited by Vedomosti, 98.9% of identified pathogens were non-influenza viruses, with swine flu, Hong Kong flu and types B and C accounting for up to 1.1%. [ 3 ]
Confirmed by several sources
- A Health Ministry institute expert said new flu strains are circulating in Russia to which the population has no immunity. [ 1 , 2 , 3 ]
- All three components of this season’s flu vaccines were changed. [ 2 , 3 ]
- The expert urged vaccination of vulnerable groups, including children, pregnant women, the elderly and people with chronic illnesses. [ 2 , 3 ]
Still unclear
- Whether the reported new strains have caused any increase in flu-specific illness. Vedomosti’s citation of Rospotrebnadzor data says 98.9% of identified pathogens were non-influenza viruses and that flu types accounted for up to 1.1%, while Kommersant quotes Lioznov saying the flu situation is stable; no figures on flu incidence itself are given.
- The exact number of cases attributed to the new strains and their severity. The documents describe the strains only through the fact that all three vaccine components were changed, without naming them or giving clinical detail.
- The basis and scope of the vaccine composition update. Only Kommersant mentions a World Health Organization recommendation behind the change; no other document states this.
- Weekly infection figures reported by Rospotrebnadzor. The 727,000 cases figure and the virological monitoring breakdown appear only in Vedomosti, dated to a September 29 statement.
- Any regional or city-level detail on where the strains are circulating. All documents describe the situation for Russia as a whole and name no location.
What local media are saying
Timeline, local time
- RIA Novosti publishes the Health Ministry expert’s statement that Russians have no immunity to new flu strains. [ 1 ]
- Kommersant reports Lioznov’s comments in detail, including the full vaccine update, vaccination advice, the two-week immunity period and full coverage of vaccine demand by Russian producers. [ 2 ]
- Vedomosti reports the same warning, citing RIA Novosti for the quote, and adds Rospotrebnadzor data on week 39 of 2026. [ 3 ]