Age-Specific Etiology of Severe Acute Respiratory Infections and Influenza Vaccine Effectivity in Prevention of Hospitalization in Russia, 2018–2019 Season

Abstract

The expansion and standardization of clinical trials, as well as the use of sensitive and specific molecular diagnostics methods, provide new information on the age-specific roles of influenza and other respiratory viruses in development of severe acute respiratory infections (SARI). Here, we present the results of the multicenter hospital-based study aimed to detect age-specific impact of influenza and other respiratory viruses (ORV). The 2018–2019 influenza season in Russia was characterized by co-circulation of influenza A(H1N1)pdm09 and A(H3N2) virus subtypes which were detected among hospitalized patients with SARI in 19.3% and 16.4%, respectively. RSV dominated among ORV (15.1% of total cases and 26.8% in infants aged ≤ 2 years). The most significant SARI agents in intensive care units were RSV and influenza A(H1N1)pdm09 virus, (37.3% and 25.4%, respectively, of PCR-positive cases). Hyperthermia was the most frequently registered symptom for influenza cases. In contrast, hypoxia, decreased blood O2 concentration, and dyspnea were registered more often in RSV, rhinovirus, and metapneumovirus infection in young children. Influenza vaccine effectiveness (IVE) against hospitalization of patients with PCR-confirmed influenza was evaluated using test-negative case–control design. IVE for children and adults was estimated to be 57.0% and 62.0%, respectively. Subtype specific IVE was higher against influenza A(H1N1)pdm09, compared to influenza A(H3N2) (60.3% and 45.8%, respectively). This correlates with delayed antigenic drift of the influenza A(H1N1)pdm09 virus and genetic heterogeneity of the influenza A(H3N2) population. These studies demonstrate the need to improve seasonal influenza prevention and control in all countries as states by the WHO Global Influenza Strategy for 2019–2030 initiative.

Metagenomic profiling of nasopharyngeal samples from adults with acute respiratory infection

“…Open Sci. 11: 240108 [23][24][25]. In the absence of influenza and RSV [18], our findings were consistent with other recent studies, where viral and bacterial ARI were predominantly associated with rhinovirus and Streptococcus spp., respectively [3].…”

“…Here we characterized the nasopharyngeal metagenome associated with ARI and assessed the concordance between mNGS and the Amplisens PCR widely used by the laboratories in the region [ 23 – 25 ]. In the absence of influenza and RSV [ 18 ], our findings were consistent with other recent studies, where viral and bacterial ARI were predominantly associated with rhinovirus and Streptococcus spp., respectively [ 3 ].…”

“…Here, we further characterized the nasopharyngeal virome associated with ARI using mNGS as part of the national initiative to enhance the diagnostic capacity for ARI in the post-pandemic era [22]. Our specific endpoint was to compare the mNGS results to those of an ARI-targeting PCR panel used commonly by clinical laboratories in Kazakhstan and the neighbouring countries [23][24][25].…”

Seasonal Influenza Vaccine Effectiveness in Persons Aged 15–64 Years: A Systematic Review and Meta-Analysis

“…A total of 123 studies from 73 papers were included in the meta-analysis. Of these studies, 9 are RCTs [ 35 , 36 , 37 , 38 , 39 ] and 114 are TNDs [ 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 …”

“… Forest plot of the vaccine effectiveness. (TND studies, TIV vaccine only, vaccine strains match circulating strains [ 45 , 57 , 78 , 87 , 90 , 92 , 93 , 94 , 97 , 98 , 100 , 101 , 104 , 107 ]). …”