An influenza A/H3 outbreak during the 2004/2005 winter in elderly vaccinated people living in a nursing home

Department of Hygiene, University of Perugia, Via del Giochetto, I-06100 Perugia, Italy.
Vaccine (Impact Factor: 3.49). 12/2006; 24(44-46):6615-9. DOI: 10.1016/j.vaccine.2006.05.037
Source: PubMed

ABSTRACT This study examined the antibody response against the three vaccine antigens and the epidemic A/H3N2 drift variant (A/California) and the prevention of laboratory diagnosed influenza infections in a group of elderly institutionalized people vaccinated with the 2004/2005 influenza vaccine. Antibody titres were measured by hemagglutination inhibition (HI) in sera collected before and 1 month after vaccination. Laboratory diagnosis was done examining throat swabs (RT-PCR or MDCK cell culture) or by serology (seroconversion comparing HI titres in sera collected 1 and 5 months after vaccination). Results obtained showed that influenza vaccination induced an adequate immune response against the three vaccine antigens and the epidemic A/H3N2 variant, however it was not capable of preventing an influenza outbreak due to the new A/H3N2 (A/California) variant.

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Available from: Michela Basileo, Jun 29, 2015
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