National Weekly Bulletin

NATIONAL WEEKLY INFLUENZA BULLETIN OF THE RUSSIAN FEDERATION

week 47 of 2022 (21.11.22 - 27.11.22)

Summary

Influenza and ARI incidence data. Influenza and other ARI activity increase of influenza and other ARI activity in Russia in comparison with previous week. The nationwide ILI and ARI morbidity level ((96.3 per 10 000 of population) was higher than national baseline (70.0) by 37.6%.

Etiology of ILI & ARI. Among 5038 patients investigation 326 (6.5%) respiratory samples were positive for influenza, including 288 cases of influenza A(H1N1)pdm09 in 32 cities, 5 cases of influenza A(H3N2) in 4 cities and 22 cases of influenza B in 8 cities.

10 influenza A(H1N1)pdm09 viruses were isolated on MDCK cell culture, including: in Astrakhan (2), Moscow (4) and Saint-Petersburg (3). Since the beginning of the season, 13 viruses A(H1N1)pdm09 and 1 virus B have been isolated.

Antigenic characterization. Since the beginning of the season, 7 influenza A(H1N1)pdm09 have been antigenically characterized by the NICs, including: Moscow (6) and Saint-Petersburg (1). All viruses were antigenically similar to reference strain A/Victoria/2570/2019 (H1N1)pdm09. 

ARVI detections. The overall proportion of respiratory samples tested positive for other ARVI (PIV, ADV, RSV, RhV, CoV, MPV, BoV) was estimated in total as 20.6% (PCR).

In sentinel surveillance system clinical samples from 83 SARI patients were investigated by rRT-PCR for influenza, among them 17 (20.5%) cases of influenza A(H1N1)pdm09. 73 SARI patients were investigated for ARVI by rRT-PCR, among them 16 (21.9%) cases of ARVI recognized including 1 case of PIV, 3 cases of ADV, 4 cases of RSV, 2 cases of RhV, 1 case of CoV, 3 cases of MPV and 2 cases of BoV infection. 1 (1.2%) of 83 SARI patients was positive for coronavirus SARS-CoV-2.

Clinical samples from 48 ILI/ARI patients were investigated for influenza by rRT-PCR, among them no positive cases recognized. Among 34 ILI/ARI samples 11 (32.4%) cases positive for ARVI detected including 1 case of PIV, 2 cases of ADV, 3 cases of RhV, 3 cases of CoV and 2 cases of MPV infection. 3 (7.7%) of 39 ILI/ARI patients were positive for coronavirus SARS-CoV-2. 

COVID-19. Totally 21 597 613 cases and 392 060 deaths associated with COVID-19 were registered in Russia including 6 785 cases and 58 deaths in last 24 hours (on 12:00 of 01.12.2022). According to the data obtained by NIC in Saint-Petersburg totally 11 819 clinical samples were PCR investigated in last week. Among them coronavirus SARS-CoV-2 detected in 901 (7.6%) cases.

Influenza and ARI morbidity data

Epidemiological data showed increase of influenza and other ARI activity in Russia in comparison with previous week. The nationwide ILI and ARI morbidity level (96.3 per 10 000 of population) was higher than national baseline (70.0) by 37.6%.

Incidence rate of clinically diagnosed influenza increased comparing to previous week and amounted to 0.91 per 10 000 of population, it was higer than pre-epidemic MEM baseline (0.060).

Hospitalization rate of clinically diagnosed influenza increased comparing to previous week and amounted to 0.19 per 10 000 of population, it was higer than pre-epidemic MEM baseline (0.040).

Influenza and ARVI laboratory testing results

Cumulative results of influenza laboratory diagnosis by rRT-PCR were submitted by 44 RBLs and two WHO NICs. According to these data as a result of 5038 patients investigation 326 (6.5%) respiratory samples were positive for influenza, including 288 cases of influenza A(H1N1)pdm09 in 32 cities, 5 cases of influenza A(H3N2) in 4 cities and 22 cases of influenza B in 8 cities.

10 influenza A(H1N1)pdm09 viruses were isolated on MDCK cell culture, including: in Astrakhan (2), Moscow (4) and Saint-Petersburg (3). Since the beginning of the season, 13 viruses A(H1N1)pdm09 and 1 virus B have been isolated.

Antigenic characterization. Since the beginning of the season, 7 influenza A(H1N1)pdm09 have been antigenically characterized by the NICs, including: Moscow (6) and Saint-Petersburg (1). All viruses were antigenically similar to reference strain A/Victoria/2570/2019 (H1N1)pdm09.

ARVI detections. The overall proportion of respiratory samples tested positive for other ARVI (PIV, ADV, RSV, RhV, CoV, MPV, BoV) estimated as 20.6% of investigated samples by PCR.

Table 1. Results of influenza and other ARVI detection by RT-PCR in Russia, week 47 of 2022

COVID-19. Totally 21 597 613 cases and 392 060 deaths associated with COVID-19 were registered in Russia including 6 785 cases and 58 deaths in last 24 hours (on 12:00 of 01.12.2022). According to the data obtained by NIC in Saint-Petersburg totally 11 819 clinical samples were PCR investigated in last week. Among them coronavirus SARS-CoV-2 detected in 901 (7.6%) cases.

Table 2. Results of influenza viruses isolation in Russia, week 47 of 2022

Sentinel influenza surveillance

Clinical samples from 83 SARI patients were investigated by rRT-PCR for influenza, among them 17 (20.5%) cases of influenza A(H1N1)pdm09. 73 SARI patients were investigated for ARVI by rRT-PCR, among them 16 (21.9%) cases of ARVI recognized including 1 case of PIV, 3 cases of ADV, 4 cases of RSV, 2 cases of RhV, 1 case of CoV, 3 cases of MPV and 2 cases of BoV infection. 1 (1.2%) of 83 SARI patients was positive for coronavirus SARS-CoV-2.

Clinical samples from 48 ILI/ARI patients were investigated for influenza by rRT-PCR, among them no positive cases recognized. Among 34 ILI/ARI samples 11 (32.4%) cases positive for ARVI detected including 1 case of PIV, 2 cases of ADV, 3 cases of RhV, 3 cases of CoV and 2 cases of MPV infection. 3 (7.7%) of 39 ILI/ARI patients were positive for coronavirus SARS-CoV-2.