Study - Immunizing children and adolescents with inactivated influenza vaccine significantly protected unimmunized residents of rural communities against influenza.

[Anne]

Immunizing children and adolescents with inactivatedinfluenza vaccine significantly protected unimmunized residentsof rural communities against influenza.

http://jama.ama-assn.org/cgi/content/full/303/10/943

Effect of Influenza Vaccination of Children on Infection Rates in Hutterite Communities

free full text

abstract


Context Children and adolescents appear to play an importantrole in the transmission of influenza. Selectively vaccinatingyoungsters against influenza may interrupt virus transmissionand protect those not immunized. Objective To assess whether vaccinating children and adolescentswith inactivated influenza vaccine could prevent influenza inother community members.
Design, Setting, and Participants A cluster randomizedtrial involving 947 Canadian children and adolescents aged 36months to 15 years who received study vaccine and 2326 communitymembers who did not receive the study vaccine in 49 Hutteritecolonies in Alberta, Saskatchewan, and Manitoba. Follow-up beganDecember 28, 2008, and ended June 23, 2009.
Intervention Children were randomly assigned accordingto community and in a blinded manner to receive standard dosingof either inactivated trivalent influenza vaccine or hepatitisA vaccine, which was used as a control.
Main Outcome Measures Confirmed influenza A and B infectionusing a real-time reverse transcriptase polymerase chain reaction(RT-PCR) assay and by measuring serum hemagglutination inhibitiontiters.
Results The mean rate of study vaccine coverage amongeligible participants was 83% (range, 53%-100%) for the influenzavaccine colonies and 79% (range, 50%-100%) for the hepatitisA vaccine colonies. Among nonrecipients, 39 of 1271 (3.1%) inthe influenza vaccine colonies and 80 of 1055 (7.6%) in thehepatitis A vaccine colonies had influenza illness confirmedby RT-PCR, for a protective effectiveness of 61% (95% confidenceinterval [CI], 8%-83%; P = .03). Among all study participants(those who were and those who were not vaccinated), 80 of 1773(4.5%) in the influenza vaccine colonies and 159 of 1500 (10.6%)in the hepatitis A vaccine colonies had influenza illness confirmedby RT-PCR for an overall protective effectiveness of 59% (95%CI, 5%-82%; P = .04). No serious vaccine adverse eventswere observed.
Conclusion Immunizing children and adolescents with inactivatedinfluenza vaccine significantly protected unimmunized residentsof rural communities against influenza.
Trial Registration clinicaltrials.gov Identifier: NCT00877396

[Anne]

Re: Effect of Influenza Vaccination of Children on Infection Rates in Hutterite Communities

oups.. same

[sharon sanders]

Re: Effect of Influenza Vaccination of Children on Infection Rates in Hutterite Communities

Thanks Anne!

[gsgs]

Re: Study - Immunizing children and adolescents with inactivated influenza vaccine significantly protected unimmunized residents of rural communities against influenza.

effectiveness =59% for vaccinated children
but 61% for people living in their "colonie"

but does lack of flu-infection increase the risk
of other respiratory diseases ?

[kiwibird]

Re: Study - Immunizing children and adolescents with inactivated influenza vaccine significantly protected unimmunized residents of rural communities against influenza.

Vaccinate kids first to halt flu spread

They're main vectors of transmission, study concludes

By SHARON KIRKEY, Canwest News ServiceMarch 10, 2010 3:03 AM

It comes too late for H1N1, but not for the next flu outbreak: new Canadian research shows vaccinating healthy children and teens first halts the spread of influenza.

..snip

The data suggests such substantial "herd immunity" in an entire community can be achieved if about 80 per cent of schoolchildren are immunized during a flu outbreak....

article goes on to quote the above study.

Read more: http://www.montrealgazette.com/healt...#ixzz0hlL7XrBk

Source: http://www.montrealgazette.com/healt...096/story.html

[gsgs]

Re: Study - Immunizing children and adolescents with inactivated influenza vaccine significantly protected unimmunized residents of rural communities against influenza.

main transmission over long distances is by adults,
presumably some high-contact-professions
then locally it's increased by children (+students ?)
before it reaches the majority