Shiloh
Editor, Senior Moderator
Source: http://www.cidrap.umn.edu/news-perspective/2020/02/flu-scan-feb-28-2020
Flu Scan for Feb 28, 2020
Flu vax strains for 2020-21; US flu activity drops, kids' deaths rise; Flu vaccine protection in children
Filed Under:
Influenza, General; Influenza Vaccines
[h=3]WHO advisors: Use 3 new strains for next Northern Hemisphere flu vaccine[/h] The World Health Organization (WHO) flu vaccine strain selection committee met this week to assess what strains to include in the 2020-21 Northern Hemisphere flu season and today recommended swapping out three of the strains.
In their report, they recommend replacing egg-based flu vaccine strains:
For trivalent vaccines that include only one influenza B strain, they recommend the Victoria lineage vaccine virus. When compared with the 2020 Southern Hemisphere vaccine strains, only the influenza B Victoria lineage is the same. The team also assessed the latest zoonotic flu viruses and didn't recommend any new candidate vaccine viruses for pandemic preparedness.
Extensive strain selection changes have sometimes led to delays in flu vaccine production. The committee meets again in September to recommend the strains to include in the Southern Hemisphere's 2021 flu season.
Feb 28 WHO recommendations for 2020-21 strains
Feb 28 WHO zoonotic flu vaccine virus assessment
Sep 27, 2019, CIDRAP News story "Two strains changed for Southern Hemisphere 2020 flu vaccine"
[h=3]CDC notes drop in flu activity, but kids' deaths climb to 125[/h] For the second week in a row, US flu levels dropped last week, the Centers for Disease Control and Prevention (CDC) said today in its weekly FluView report.
Though regions are still experiencing elevated influenza activity, several indicators showed flu activity was declining. However, 20 more pediatric deaths were recorded, raising the 2019-20 flu season total to 125, compared with 144 for all of last season.
Rates of outpatient visits for influenza-like illness (ILI) dropped last week, to 5.5%, compared with the previous week's 6.1%. The percentage of specimens positively identified as influenza also dropped slightly, from 29.6% to 26.4%.
The number of jurisdictions reporting high ILI activity was 43 states and New York City and Puerto Rico. The number of jurisdictions reporting regional or widespread flu remained at 48.
"Overall, hospitalization rates remain similar to this time during recent seasons, but rates among school aged children and young adults are higher at this time than in recent seasons and rates among children 0-4 years old are now the highest CDC has on record at this point in the season, surpassing rates reported during the second wave of the 2009 H1N1 pandemic," the CDC said.
The cumulative hospitalization rate rose from 47.4 per 100,000 population, to 52.7 per 100,000.
Public health labs confirmed that 72.4%% of positive specimens were influenza A and 27.6% were influenza B. Of the subtyped influenza A specimens, 94.8% were 2009 H1N1, and 5.2% were H3N2. Influenza B/Victoria accounted for 99.3% of B viruses detected.
Feb 28 CDC FluView
[h=3]Children derive significant protection from flu vaccines, review finds[/h] A systematic review and meta-analysis of 28 studies of flu vaccine effectiveness (VE) against hospitalization in children published yesterday in Vaccine found overall VE of 57.5% and VE against H1N1 of 74.1%, H3N2 of 40.8%, and influenza B of 50.9%.
The study, led by Brown University researchers, compared the findings of test-negative design trials from 2005 to 2019 that estimated flu VE with laboratory-confirmed flu-related hospitalizations in children 6 months to 17 years old.
The researchers found that flu vaccine conferred significant protection against any type of flu-related hospitalization (57.5%; 95% confidence interval [CI], 49.5% to 65.5). VE was high against H1N1 (74.1%; 95% CI, 54.9% to 93.3%) and moderate against influenza B (50.9%; 95% CI, 41.8% to 60.0%) and H3N2 (40.8%; 95% CI, 25.7% to 55.9%). Flu VE was 61.7% in children younger than 5 years (95% CI, 49.3% to 74.1%) and 54.4% in those 6 to 17 years (95% CI, 35.1% to 73.6%). And flu vaccination conferred significantly higher protection in fully vaccinated children (61.8%; 95% CI, 54.5% to 69.1%) than in those only partially vaccinated (33.9%; 95% CI, 21.1% to 46.7%).
While vaccination is the most effective way to prevent the flu, VE varies by year in part because of circulating seasonal flu strains' antigenic variability and their match with the vaccine strains. Children, particularly those younger than 5 years, and older adults are at highest risk for flu-related complications, hospitalizations, and death. Children also tend to introduce and spread the virus at home and in the community, the authors note.
Feb 27 Vaccine abstract
Flu Scan for Feb 28, 2020
Flu vax strains for 2020-21; US flu activity drops, kids' deaths rise; Flu vaccine protection in children
Filed Under:
Influenza, General; Influenza Vaccines
[h=3]WHO advisors: Use 3 new strains for next Northern Hemisphere flu vaccine[/h] The World Health Organization (WHO) flu vaccine strain selection committee met this week to assess what strains to include in the 2020-21 Northern Hemisphere flu season and today recommended swapping out three of the strains.
In their report, they recommend replacing egg-based flu vaccine strains:
- H1N1 (A/Brisbane/02/2018-like) with A/Guangdong-Maonan/SWL1536/2019-like
- H3N2 (A/Kansas/14/2017-like virus) with A/Hong Kong/2671/2019-like
- B Victoria (B/Colorado/06/2017-like) with B/Washington/02/2019-like
For trivalent vaccines that include only one influenza B strain, they recommend the Victoria lineage vaccine virus. When compared with the 2020 Southern Hemisphere vaccine strains, only the influenza B Victoria lineage is the same. The team also assessed the latest zoonotic flu viruses and didn't recommend any new candidate vaccine viruses for pandemic preparedness.
Extensive strain selection changes have sometimes led to delays in flu vaccine production. The committee meets again in September to recommend the strains to include in the Southern Hemisphere's 2021 flu season.
Feb 28 WHO recommendations for 2020-21 strains
Feb 28 WHO zoonotic flu vaccine virus assessment
Sep 27, 2019, CIDRAP News story "Two strains changed for Southern Hemisphere 2020 flu vaccine"
[h=3]CDC notes drop in flu activity, but kids' deaths climb to 125[/h] For the second week in a row, US flu levels dropped last week, the Centers for Disease Control and Prevention (CDC) said today in its weekly FluView report.
Though regions are still experiencing elevated influenza activity, several indicators showed flu activity was declining. However, 20 more pediatric deaths were recorded, raising the 2019-20 flu season total to 125, compared with 144 for all of last season.
Rates of outpatient visits for influenza-like illness (ILI) dropped last week, to 5.5%, compared with the previous week's 6.1%. The percentage of specimens positively identified as influenza also dropped slightly, from 29.6% to 26.4%.
The number of jurisdictions reporting high ILI activity was 43 states and New York City and Puerto Rico. The number of jurisdictions reporting regional or widespread flu remained at 48.
"Overall, hospitalization rates remain similar to this time during recent seasons, but rates among school aged children and young adults are higher at this time than in recent seasons and rates among children 0-4 years old are now the highest CDC has on record at this point in the season, surpassing rates reported during the second wave of the 2009 H1N1 pandemic," the CDC said.
The cumulative hospitalization rate rose from 47.4 per 100,000 population, to 52.7 per 100,000.
Public health labs confirmed that 72.4%% of positive specimens were influenza A and 27.6% were influenza B. Of the subtyped influenza A specimens, 94.8% were 2009 H1N1, and 5.2% were H3N2. Influenza B/Victoria accounted for 99.3% of B viruses detected.
Feb 28 CDC FluView
[h=3]Children derive significant protection from flu vaccines, review finds[/h] A systematic review and meta-analysis of 28 studies of flu vaccine effectiveness (VE) against hospitalization in children published yesterday in Vaccine found overall VE of 57.5% and VE against H1N1 of 74.1%, H3N2 of 40.8%, and influenza B of 50.9%.
The study, led by Brown University researchers, compared the findings of test-negative design trials from 2005 to 2019 that estimated flu VE with laboratory-confirmed flu-related hospitalizations in children 6 months to 17 years old.
The researchers found that flu vaccine conferred significant protection against any type of flu-related hospitalization (57.5%; 95% confidence interval [CI], 49.5% to 65.5). VE was high against H1N1 (74.1%; 95% CI, 54.9% to 93.3%) and moderate against influenza B (50.9%; 95% CI, 41.8% to 60.0%) and H3N2 (40.8%; 95% CI, 25.7% to 55.9%). Flu VE was 61.7% in children younger than 5 years (95% CI, 49.3% to 74.1%) and 54.4% in those 6 to 17 years (95% CI, 35.1% to 73.6%). And flu vaccination conferred significantly higher protection in fully vaccinated children (61.8%; 95% CI, 54.5% to 69.1%) than in those only partially vaccinated (33.9%; 95% CI, 21.1% to 46.7%).
While vaccination is the most effective way to prevent the flu, VE varies by year in part because of circulating seasonal flu strains' antigenic variability and their match with the vaccine strains. Children, particularly those younger than 5 years, and older adults are at highest risk for flu-related complications, hospitalizations, and death. Children also tend to introduce and spread the virus at home and in the community, the authors note.
Feb 27 Vaccine abstract