Temperature record: the incidence of acute respiratory viral infections has begun to grow in the regions of the Russian Federation

In the Vologda and Ryazan regions, Crimea and Sevastopol, as well as in Kabardino-Balkaria and three other regions, local Rospotrebnadzor departments recorded an increase in the incidence of acute respiratory viral infections. In particular, in Nalchik, the epidemiological threshold among schoolchildren has been exceeded by 30%. The Influenza Research Institute notes that the epidemic situation in the country remains unfavorable. Despite the fact that the peak of seasonal morbidity has already passed, experts attribute the increase in the number of patients to changeable weather. About where else there is an increase in cases of influenza and acute respiratory viral infections and why, see the Izvestia article.

Where the incidence is growing

An increase in the incidence of acute respiratory viral infections and influenza was recorded in at least eight regions on the 17th week (April 20-26), Izvestia calculated. So, in Crimea, the indicator increased by 18.36%, the regional Rospotrebnadzor reported.

"6,698 people fell ill, the figure was 35.08 per 10,000 people, which is 2.78% higher than the epidemic threshold," they added.

In Sevastopol, the growth also amounted to 18.36% compared to the previous week, but the level remains below the epidemic threshold by 23.49%.

In Khanty-Mansi Autonomous Okrug, the incidence of influenza increased by 25.5%. Children under the age of two and aged three to six were the most vulnerable. At the same time, the level of acute respiratory viral infections remained stable — 94 cases per 10,000 population. In this regard, 20 classes in 13 schools have been transferred to distance learning, and pupils from 17 groups of 13 kindergartens have also been sent to remote training.

4.9 thousand cases of acute respiratory viral infections and influenza were recorded in the Ryazan region. "This is above the level of the previous week by 7%. Residents of the regional center accounted for 73% of the cases," the local Rospotrebnadzor noted.

About 4.5 thousand cases of acute respiratory viral infections and influenza were diagnosed in the Murmansk Region during this period. Such data was provided by the local department of Rospotrebnadzor. More than 44% of patients are children, among them 30.8% are preschoolers aged three to six years, and 48% are schoolchildren.

In the Vologda region, the number of cases of acute respiratory viral infections increased by 4.2% compared to the previous week, the regional Ministry of Health reported. And in Nalchik (Kabardino-Balkaria), the incidence among schoolchildren aged 7-14 exceeded the weekly epidemic threshold by 30.5%, the local department of Rospotrebnadzor clarified. A week earlier, in this age group, on the contrary, the indicator was below the threshold by 18.7%.

More than 5.4 thousand cases of acute respiratory viral infections and influenza have been registered in the Kaluga Region. According to the regional Rospotrebnadzor, the number of patients among schoolchildren increased by 23.2%, among preschoolers — by 2.2%. In adults, the epidemic threshold is exceeded by 1.3%. In the Kostroma region, the incidence rate increased by 7.5% in a week. Against the background of the epidemiological situation, restrictive measures have been introduced in eight districts, 17 groups in 13 kindergartens have been completely quarantined.

At the same time, the decline in acute respiratory viral infections and influenza is noted in the Kemerovo, Pskov and Irkutsk regions, as well as in Mari El. In the Leningrad Region, its level decreased by 23.8%. In the Perm Region and Moscow, the incidence rate remained at the level of the previous week, the regional offices of Rospotrebnadzor reported.

On average, there is a slight decrease in cases of influenza and acute respiratory viral infections in Russia, according to the Smorodintsev Influenza Research Institute. The figure is 51.5 per 10,000 people, which is 30.9% lower than the weekly epidemic threshold. In the previous week, this figure was 51.6.

"In the 17th week of 2026, the epidemic thresholds for the total incidence of influenza and acute respiratory viral infections in the entire population were not exceeded by 20% or more in any of the 61 cities that sent the data," they said.

The Influenza Research Institute noted that the overall situation with influenza in the country remains stable, but with acute respiratory viral infections it is unfavorable.

Epidemic prologue: the incidence of acute respiratory viral infections and influenza is growing in 20 regions

The number of patients is increasing due to temperature fluctuations

Why is the incidence increasing

Compared to previous years, the incidence of acute respiratory viral infections and influenza in Russia has been exceeded by 2.5%, infectious diseases specialist and virologist Elena Malinnikova told Izvestia.

— It is caused by more than 250 different viruses. One epidemiological season stretches until the next," she noted. — Influenza is mainly prevalent in November, January and March, rhinoviruses in September, October, December and January, adenovirus infections in March, April, May and so on. They gradually turn into one another, and the symptoms are similar.

According to her, infection usually occurs not with one virus, but with several at once. At the same time, the cold weather that unexpectedly came to the Russian regions will not in itself cause an increase in the incidence, said Elena Malinnikova. However, such a period is a stressful factor that creates conditions for virus attacks.

Gennady Onishchenko, academician of the Russian Academy of Sciences, epidemiologist and Deputy president of the Russian Academy of Education, believes that the sharp cold snap caused the increase in the number of SARS and flu cases.

"People had already relaxed and were ready to immerse themselves in the warm season — and suddenly there was a sharp cold snap," he said.

A similar opinion is shared by Elizaveta Petrova-Kolosova, a pediatrician at the children's clinic "Be Healthy" on Sushchevsky Val.

— The incidence of acute respiratory infections begins to increase at air temperatures from 0 °C to -5 °C. Favorable conditions for viruses are being created, and local immunity of the mucous membranes of the respiratory tract is decreasing," she said.

In addition, cold air combined with high humidity creates conditions that promote the spread of respiratory viruses, the doctor added.

According to Gennady Onishchenko, despite the increase in the incidence of acute respiratory viral infections and influenza in some regions, the general trend signals a decline.

— There is a slight rise now, it is non—epidemic, - he said.

According to him, after the May holidays, a significant increase in the number of cases in the country is not expected, as the disease season is almost over.